This document discusses the levels of organization in the human body from cells to organisms. It defines key terms like cells, tissues, organs, and organ systems. It explains that cells make up tissues, tissues make up organs, and organs work together in organ systems. Some key organ systems mentioned are the digestive system, circulatory system, and respiratory system. The relationship between cells, tissues, organs, systems and organisms is illustrated through a flow chart. The document provides a high-level overview of the hierarchical structure of the human body.
2. From Cells to Or
ganisms
Dr Ahmad Ali Qureshi
(MBBS,GMC)
PharmoHub Pakistan
3. 1. Define: Cell, Tissue, organ, and organ sys
tem (DK).
2. Describe two types of tissue (DK)
3. Describe two types of organs (DK)
4. Create a flow chart illustrating relationshi
p between cells, tissues, organs, systems an
d organisms (PK)
Lesson Objectives
4. Levels of Organization
Cell—Basic unit of structure and function in orga
nisms.
Some organisms, like bacteria and protists, are
unicellular (made entirely of one cell).
Some organisms, like fungi, plants, and animal
s, are multicellular (made of many cells).
In multicellular organisms, cells exhibit cell spe
cialisation. They take on specific jobs and loo
k different from each other.
The cells also exhibit division of labor. They spli
t up the work of the organism.
5.
6. Levels of Organization
Tissues—Groups of similar cells that work to
gether to perform a specific function.
4 major tissue types in animals
Epithelial tissue
Connective tissue
Muscle tissue
Nervous tissue
7. Levels of Organization
Organs—structures made of different types of
tissues that work together to perform a specifi
c function.
Examples
Heart
Lungs
Stomach
Small intestine
Liver
Large Intestine
Gall Bladder
Plant Roots
Plant Stems
Plant Leaves
8. Levels of Organization
Organ Systems—Groups of organs that w
ork together to perform a specific functio
n.
Examples:
Digestive system
Circulatory system
Respiratory system
Nervous system
Muscular system
Skeletal system
Integumentary system (skin)
Vascular system in plants
9. Levels of Organization
Organism—A complete, individual living t
hing.
Examples:
A single person
A single plant
A single bacterium
A single protist
10.
11. Write your answers in complete sentences
Q 1: A (tissue, organ, system) is a group of the same kinds of cells that work together.
Choose the right answer.
system
organ
tissue
Q 2: Some tissues and organs work together like the members of the team. The parts
that work together are called a _____________.
cell
system
group
Q 3: The mouth, teeth, tongue, stomach and intestines all work together. Therefore th
ey are called the important parts of __________________.
digestive system
circulatory system
muscular system
Q 4: Brain, heart and lungs are some of the important _______________ in a body.
organs
tissues
cells
system
Q 5: Different tissues work together to form _________ .
cells
system
organs
Q 6: Different systems work together to form organs. True or false?
false
true
12. 11
Organization of Vertebrate Bo
dy
Tissues are groups of cells that are sim
ilar in structure and function
In humans, there are four primary tiss
ues:
-Epithelial, connective, muscle and
nerve
13. 12
Organization of Vertebrate Bo
dy
Organs are combinations of different tissues
that form a structural and functional unit
Organ systems are groups of organs that co
operate to perform the major activities of
the body
-The human body contains 11 principal or
gan systems
14. Organ Systems
The five main organ systems that we will b
e focusing on in this unit are:
The Respiratory System
The Circulatory System
The Reproductive System
The Digestive System
The Excretory System
17. 16
Circulatory System
NO Thank
you!
The system that carries ox
ygen and nutrients to all
cells in the body and tak
es wastes away from the
cells; it consists of the he
art, blood vessels and blo
od.
18. 17
Respiratory System
NO
Thank you!
The system involved in th
e inhalation of and diffusi
on of oxygen into the blo
od stream, and the remo
val of carbon dioxide fro
m the body via exhalatio
n
19. Excretory System
The system resp
onsible for the r
emoval of exce
ss water and w
aste from cell r
eactions in the
body
20. Reproductive System
The male and female reproductive systems are responsi
ble for the production of sperm and ova (eggs), the fertil
isation of ova by sperm, and the gestation of a fertilised
ova into a foetus (unborn baby)
22. Human Anatomy:
Its is defined in various ways :-
“It is the study of structure of human body”
23. c) Its is defined as an important scientific
discipline which is concerned with the i
nvestigation of biological structure by :
i) Dissection ;
ii) Microdissection ;
iii) Light microscopy ;
iv)Electron microscopy ;
v) Radiology ;
24. Regional anatomy :
Its deals with anatomy of various structures as they
lie in relationship with one another in different re
gion of the body . It is valuable for surgeons.
.
25.
26. invisible
Surface anatomy:
It deals with the study and identification
of various structures in the living person
by methods of inspection and palpation
It helps to enhance the knowledge acqui
red through dissection of the cadaver by
either of line of study, Regional or syste
matic. It is helpful both in health and di
sease and is daily used in medical practi
ce.
27.
28. Radiological Anatomy
It deals with the study of structure of hu
man body with the aid of X-Rays. It helps
to investigate the anatomical facts which
cannot be understood by any other meth
od. It is very useful both in health and di
sease and is in current use in modern m
edical practice.
29.
30. Embryology
It is the study of various changes in the developing orga
nism from the fertilization of ovum up to the birth of t
he baby.
33. Histology
It is the study of various tissues by various scientific met
hod (microscopy ; histochemistry etc.).
34. Applied / Clinical Anatomy
It is the direct application of facts of human anatomy to
medicine and surgery. The students are advised to lay t
he stress on applied aspects while they are studying gr
oss anatomy in dissection hall.
35. Systemic Anatomy
The description of several systems of organs separately a
nd in logical order comes under the head of systematic
anatomy. The several parts of each system not only sho
w a certain similarity of structure but are also associate
d in specialized functions.
36. Anatomical
Terminologies
Anatomic position is a specific
body position in which an indi
vidual stands upright with the
feet parallel and flat on the fl
oor.
The head is level, and the eye
s look forward toward the obs
erver.
The arms are at either side of
the body with the palms facin
g forward and the thumbs poi
nting away from the body.
37. Anatomical Terminology
A plane is an imaginary surface that slices t
he body into specific sections.
The three major anatomic planes of referen
ce are the coronal, transverse, and sagittal
planes.
38.
39. Sections and
Planes
A coronal plane, also ca
lled a frontal plane, is a
vertical plane that divid
es the body into anterio
r (front) and posterior (
back) parts.
40. Sections and
Planes
A transverse plane, also cal
led a cross-sectional plane
or horizontal plane, cuts p
erpendicularly along the lo
ng axis of the body or orga
n separating it into both su
perior (upper) and inferior
(lower) parts.
41. Sections and
Planes
A sagittal plane or m
edian plane, extends
through the body or
organ vertically and
divides the structure
into right and left hal
ves.
42. Sections and Planes
A sagittal plane in the body midline is a midsagitta
l plane.
A plane that is parallel to the midsagittal plane, b
ut either to the left or the right of it, is termed a p
arasagittal (or sagittal) plane.
A minor plane, called the oblique plane, passes th
rough the specimen at an angle.
43. Directional Terms of the Bod
y
Directional terms are precise and brief, and
for most of them there is a correlative term
that means just the opposite.
44. Relative and Directional Terms of
the Body
Relative to front (belly side) or back (
back side) of the body :
Anterior = In front of; towar
d the front surface
Posterior = In back of; towa
rd the back surface
Dorsal =At the back side of
the human body
Ventral = At the belly side o
f the human body
45. Relative and Directional Terms of
the Body
Relative to the head or t
ail of the body:
Superior = Toward the head o
r above
Inferior = Toward feet not he
ad
Caudal = At the rear or tail en
d
Cranial = At the head end
46. Relative and Directional Terms of
the Body
Relative to the midline or center of th
e body:
Medial = Toward the midlin
e of the body
Lateral = Away from the mi
dline of the body
Deep = On the inside, under
neath another structure
Superficial = On the outside
47. Relative and Directional Terms of
the Body
Relative to point of atta
chment of the appenda
ge:
Proximal = Closest to
point of attachment t
o trunk
Distal = Furthest fro
m point of attachme
nt to trunk
48.
49. Body Regions
The human body is partitioned into two ma
in regions, called the axial and appendicular
regions.
the axial region includes the head, neck, and tr
unk which comprise the main vertical axis of o
ur body
our limbs, or appendages, attach to the body’s
axis and make up the appendicular region
50. 7-30
Skeletal System
The axial skeleton is composed of the bones along the ce
ntral axis of the body,
the skull
the vertebral column
the thoracic cage
The appendicular skeleton consists of the bones of the a
ppendages
upper and lower limbs
the bones that hold the limbs to the trunk of the body.
55. CELL STRUCTURE
Cell form the basic structural and functional
unit of human body. These are of two types
1:somatic cells
2:sex cells
56. CELL mEmbRANE
The cell membrane is a biological membrane
that separates the interior of all cells from the
outside environment which protects the cell
from its environment. The cell membrane
consists of a lipid bilayer, including cholesterols
that sit between phospholipids to maintain
their fluidity at various temperatures.
57.
58.
59. FUNCTIONS OF CELL mEmbRANE
● 1_ it forms cell boundaries and acts as a barrier between
cytoplasm and extracellular fluid environment.
2_ through it substances are exchanged between cell
and its environment.compounds of high molecular weight
are exchanged by special processes known as
endocytosis and exocytosis.
3_ it plays an important role in the maintainance of cell
shape.
4_ in certain cells it acts as a medium for conduction of
electrical impulses.
61. NUCLEUS
It contains the genetic materials and has a direct
influence on metabolic activities of cytoplasm. It is
surrounded by a membrane called NUCLEAR
ENVELOPE. There are one or more rounded darkly
staining bodies called NUCLEOLI. A semi fluid
material called the nuclear ground substance or
NUCLEAR SAP fills the space within the nucleus.
NUCLEAR ENVELOPE consists of two
closely apposed membranes. At numerous points there
are openings in envelope also known as NUCLEAR
PORES. These serve as channels through which
substances pass into and out of the nucleus.
62. ●CHROmATIN which is the granules and
particles of a basophilic material consists of DNA and
associated basic proteins. DNA exists in the form of
flexible rod like structures called CHROMOSOMES. The
number and characteristics of chromosomes encountered
in an individual is known as karyotype.
NUCLEOLIare rounded dense well defined
bodies not curcumscribed by a membrane. It is composed
of ribonucleic acid RNA and associated proteins.
63.
64. CYTOPLASm
● Most of the metabolic processes of cell occurr in
cytoplasm. It is often divided in three parts
1: centrosome
2: endoplasm
3: ectoplasm
the term CYTOSOL are used for the component
of cytoplasm which occupies space between
organelles inclusions and elements of cytoplasm.
65. ORGANELLES
● The term organelle literally means little organs. They carry out various special functions essential to life and metabolism of cell.
1_ mITOCHONDRIA
mitochondrion is bounded by two unit membranes. The inner one is
thrown into folds called CRISTAE. The inner surface of internal
membrane as well as cristae is lined by elemantary particles which are
connected to membrane by means of a slender stalk.
FUNCTIONS OF mITOCHONDRIA
these are the major energy source of the cell. They transform
chemical energy of metabolites present in the cytoplasm into
available energy easily accessible to the cell.
66.
67.
68. GOLGI APPARATUS
● GOLGI APPARATUS appears as a number of curved
stacks of closely packed membranous cisternae
associated with small vesicles and large vacuoles. These
are completely devoid of ribosomes. Their chief function
is the concentration and packing of secretory products of
the cell.
● RIbOSOmES are small bodies present in all
animal cells except mature RBCs. These are the sites
where amino acids are incorporated into polypeptides
and
69.
70. LYSOSOmES
●are small roughly spherical bodies limited by a single
membrane. These contain hydrolytic enzymes which are
capable of degrading almost all types of biological
macromolecules. These carry out intracellular digestion.
●
CYTOPLASmIC INCLUSIONS
1: LIPIDS
2:GLYCOGEN
3:PIGMENTS
4:CRYSTALS
5:SECETORY GRANULES
71. CYTOSKELETON
●consists of a complex network of filaments and
microtubules. It plays an important role in
maintenance of cell shape, stabilization of cell
attachments and cellular movements.
FILAMENTS include thick, thin and intermediate
filaments.
MICROTUBULES are long hollow cylindrical
structures which do not branch. They are formed by
polymerization of a protein called tubulin.
Polymerization occurs at microtubules organizing
centers.
72.
73. VACUOLE
● A vacuole is a membrane-bound cell organelle.
In animal cells, vacuoles are generally small and
help sequester waste products. In plant
cells, vacuoles help maintain water balance.
Sometimes a single vacuole can take up most of
the interior space of the plant cell.
74. ENDOPLASmIC RETICULUm
● The endoplasmic reticulum (ER) is a
large organelle made of membranous sheets
and tubules that begin near the nucleus and
extend across the cell. The endoplasmic
reticulum creates, packages, and secretes many
of the products created by a cell. Ribosomes,
which create proteins, line a portion of the
endoplasmic reticulum.
75. Rough Endoplasmic Reticulum (RER) Smooth Endoplasmic Reticulum
(SER)
It possesses ribosomes attached to its
membrane.
It does not have ribosomes on its
membrane.
Formed of cisternae and a few tubules. Formed of vesicles and tubules.
It participates in the synthesis of
enzymes and proteins.
Synthesises glycogen, lipids and
steroids.
It helps in the formation of lysosomes. Gives rise to
Spherosomes/ Oleosomes
It is internal and connected with the
nuclear envelope.
It is peripheral and may be connected
to plasmalemma.
Ribophorins are present and help
ribosomes attach to ER
Devoid of Ribophorins.
It might develop from the nuclear
envelope
Develops from Rough Endoplasmic
Reticulum.
Provides proteins and lipids for Golgi
apparatus.
Provides vesicles for cis-face of Golgi
apparatus.
78. Dr Ahmad Ali Qureshi
(MBBS,GMC)
PharmoHub Pakistan
79.
80. As human body develops from
single to multicellular, cells
specialize.
Body is interdependent system,
malfunction of one group of cells
is catastrophic.
Cells specialize into types of
tissues, then interspersed into
organs.
81. Epithelium
◦ Coverings
◦ Linings of
surfaces
Connective
◦ Support
◦ Bone, ligaments,
fat
Muscle
◦ Movement
Nervous
◦ Control
◦ Brain, nerves,
spinal cord
83. Protection
◦ Skin protects from sunlight & bacteria & physical
damage.
Absorption
◦ Lining of small intestine, absorbing nutrients into
blood
Filtration
◦ Lining of Kidney tubules filtering wastes from
blood plasma
Secretion
◦ Different glands produce perspiration, oil,
digestive enzymes and mucus
84. Form continuous sheets (fit like tiles)
Apical Surface
◦ All epithelial cells have a top surface that borders
an open space – known as a lumen
Basement Membrane
◦ Underside of all epithelial cells which anchors them
to connective tissue
Avascularity (a = without)
◦ Lacks blood vessels
◦ Nourished by connective tissue
Regenerate & repair quickly
85. Cell Shape
◦ Squamous – flattened like fish
scales
◦ Cuboidal - cubes
◦ Columnar - columns
Cell Layers
◦ Simple (one layer)
◦ Stratified (many layers)
Named for the type of cell at the
apical surface.
86. Structure
◦ Single Layer of flattened cells
Function
◦ Absorption, and filtration
◦ Not effective protection – single layer of cells.
Location
◦ Walls of capillaries, air sacs in lungs
◦ Form serous membranes in body cavity
87.
88. Structure
◦ Single layer of cube shaped cells
Function
◦ Secretion and transportation in glands, filtration in
kidneys
Location
◦ Glands and ducts (pancreas & salivary), kidney
tubules, covers ovaries
89.
90. Structure
◦ Elongated layer of cells with nuclei at same level
Function
◦ Absorption, Protection & Secretion
◦ When open to body cavities – called mucous
membranes
Special Features
◦ Microvilli, bumpy extension of apical surface,
increase surface area and absorption rate.
◦ Goblet cells, single cell glands, produce
protective mucus.
Location
◦ Linings of entire digestive tract
91.
92. Structure
◦ Irregularly shaped cells with nuclei at different
levels – appear stratified, but aren’t.
◦ All cells reach basement membrane
Function
◦ Absorption and Secretion
◦ Goblet cells produce mucus
◦ Cilia (larger than microvilli) sweep mucus
Location
◦ Respiratory Linings & Reproductive tract
94. Structure
◦ Many layers (usually cubodial/columnar at bottom
and squamous at top)
Function
◦ Protection
◦ Keratin (protein) is accumulated in older cells near
the surface – waterproofs and toughens skin.
Location
◦ Skin (keratinized), mouth & throat
97. Structure
◦ Many layers
◦ Very specialized – cells at base are cuboidal or
columnar, at surface will vary.
◦ Change between stratified & simple as tissue is
stretched out.
Function
◦ Allows stretching (change size)
Location
◦ Urinary bladder, ureters & urethra
98.
99.
100.
101. One or more cells that make and secrete a
product.
Secretion = protein in aqueous solution:
hormones, acids, oils.
Endocrine glands
◦ No duct, release secretion into blood vessels
◦ Often hormones
◦ Thyroid, adrenal and pituitary glands
Exocrine glands
◦ Contain ducts, empty onto epithelial surface
◦ Sweat, Oil glands, Salivary glands, Mammary
glands.
102. Branching
Simple – single, unbranched duct
Compound – branched.
Shape: tubular or alveolar
Tubular – shaped like a tube
Alveolar – shaped like flasks or sacs
Tubuloalveolar – has both tubes and sacs in
gland
103.
104.
105.
106.
107. The basement membrane is a thin, pliable
sheet-like type of extracellular matrix, that
provides cell and tissue support and acts as a
platform for complex signalling.
The basement membrane is composed of
collagen type IV, laminins, entactin/nidogen,
and proteoglycans that the epithelial cells
themselves secrete.
It is a non-cellular structure.
108. It serves to bind the epithelium with the
underlying or surrounding connective tissue.
It serves as a sieve or ultrafilter i.e passes
small molecules and impedes transport of
large molecules.
It serves as a scaffold during epithelial
regeneration or wound healing.
Plays an important role in cell growth ,
proliferation and differentiation.
112. Connective Tissue
Function:
- Binds structures together
- Provides support & protection
- Fills spaces
- Produces blood cells
- Stores fat
For energy, insulation, organ protection
113. Structure:
- Tissue cells are widely separated by
extracellular matrix
- Can be solid, semisolid, or liquid
Matrix of connective tissue determine its
properties
114. Fibers of the Matrix
White fibers – contain collagen which
gives the fibers flexibility and strength
Yellow fibers – contain elastin more elastic
than collagen but not as strong
Reticular fibers – thin, highly branched
collagenous fibers that provide support
117. A. Loose (areolar) Connective Tissue
Lies between other
tissues or between
organs binding them
Cells made of
fibroblasts – large,
star-shaped cells
Contains many white
fibers (strong and
flexible) and yellow
fibers (very elastic)
118.
119. Adipose tissue is a
type of loose
connective tissue
- stores fats,
provides insulation
- found beneath
skin, around kidney
& heart, breast
120.
121. B. Dense Connective Tissue
Regular
Consists of parallel
bundles of
collagenous fibers
Found in tendons &
ligaments
Binds organs together
Irregular
Bundles run in
different direction
Found in inner portion
of skin
123. C. Reticular Connective
Has reticular cells and
reticular fibers
Also called lymphatic
tissue
Found in lymph nodes,
spleen, thymus, and red
bone marrow
Store and produce white
blood cells
Part of immune system
124.
125. 2. Cartilage
The cell
(chondrocytes)
lies in small
chambers called
lacunae
Matrix is solid yet
flexible
Lacks direct
blood supply, as
a result, it heals
slowly
127. A. Hyaline Cartilage
Most common
Matrix contains fine collagenous fibers
Glassy, white, opaque
Found in the nose, ends of the long bones
and ribs, rings in the trachea
128.
129. B. Elastic Cartilage
Contains elastic and
collagenous fibers
Found in the outer
ear
130.
131. C. Fibrocartilage
Matrix contains strong
collagenous fibers
Function: absorbs
shocks and reduces
friction between joints
Found in the pads
between the
vertebrae and knee
joints
136. Definition of Bone...
“Bone is the substance that forms the skeleton of the body. It is
composed chiefly of calcium phosphate and calcium carbonate”
funCtions of Bone…
The human skeleton serves six major functions
Support
Movement
Protection
Production of blood cells
Storage of iron
Endocrine regulation
137. (1) What are the Bone Regions?
Axial
Down the center of body
Skull, vertebral column, rib cage, center pelvis
Appendicular
Off the sides of body
Upper and lower limbs, shoulder and hip bones
138.
139. Axial Skeleton (Head + Neck +Trunk)
SKULL 22 Bones
Ear Ossicle (3+3) 6 Bones
Hyoid 1 Bone
Vertebral coloumn 33 Bones
Ribs (12+12) 24 Bones
Sternum 1 bones
Total = 80 Bones
Appendicular Skeleton (upper lim+lower limb)
Upper limb (Right 32+ Left 32) 64 Bones
Lower limb (Right 31+ Left 31) 62 Bones
Total = 126 Bones
GrAnD totAl 80+126=206 Bones
140. DeveloPmentAl ClAssifiCAtion
memBrAne Bones…
Bone formed directly in connective tissue, i.e. by intramembranous
ossification, rather than by replacing cartilage (compare cartilage bone). Small
areas of membrane become jelly-like and attract calcium salts
Examples = Some face bones, skull bones, and part of the clavicle
are membrane bones.
CArtilAGenous BoBes…
Intracartilaginous ossification • In intra cartilaginous ossification →
cartilaginous model is formed which is closely resemble the bone to be formed.
•This cartilage is subsequently replaced by (not converted into) bone. eg.
Almost all of the long bones.
memBrAnoCArtilAGenous Bones…
These bones develop partly in membranes and partly in cartilage.
Example=Occipital,Temporal,sphenoid bones of the skull, mandible, clavicle
141. (2) What are the types of Bones?
Long
Short
Flat
Irregular
142.
143. (3) Long Bones
Longer than they are wide
Has a shaft and 2 ends
Weight bearing bones (like steel beams)
Provide the greatest structure and support
Examples:
All limb bones
Except…. Kneecap,Wrist and Ankle bones
144.
145. (4) Short Bones
Nearly same length,width,thickness but shape irregularly
Allow for wider range of movement
Examples:
Wrist (carpals)
Ankle (tarsals)
149. (6) Irregular Bones
Complicated, unusual shapes
Muscles, tendons, ligaments usually attach to these
Examples:
Vertebrae
Hip bones
150.
151. (8) Bone Structure
Unique based on location + bone type.
Compact Bone (Outer Layer):
Dense
Smooth and Solid to naked eye
Spongy Bone (Inner Layer):
Hole-y (like a honeycomb)
Made of small needle-like, flat pieces called “trabeculae”
Open spaces between trabeculae are filled with red or yellow bone marrow
152.
153. (9) Structure of a Long Bone
Diaphysis:
Center, main shaft
Long part of bone
Made of very thick compact bone surrounding a central marrow cavity
Epiphysis:
Ends of bone
Wider than diaphysis
Made of compact bone which surrounds spongy bone.
Joint surface of each epiphysis is covered with hyaline cartilage
154. Epiphyseal Line:
Remnant of Epiphyseal Plate
Found in adult bones
Shows amount of cartilage growth during adolescence
Membranes:
Periosteum = Around the outside
Richly supplied with nerve fibers, lymphatic vessels and blood vessels
Provides anchoring points for tendons and ligaments
Endosteum = Around the inside
Surrounds the spongy bone
155.
156. (12) Chemical Composition of Bone
Contains organic & inorganic components
Organic:
Cells (osteoblasts, osteocytes, osteoclasts)
Osteoid
Made of glycoproteins and collagen fibers
Secreted by osteoblasts
“filler matrix” around cells
Contribute to flexibility and tensile strength
Inorganic:
Mineral Salts (calcium phosphates)
Contribute to hardness of bone (allowing for compression resistance)
162. Rule of direction of nutrient foramen
Nutrient foramen directed against the growing end
“ Towards the Elbow we go; from the knee we flee.”
Nutrient artery
Metaphysial arteries
Epiphyseal arteries
Periosteal arteries
163. Venous Drainage
Venous sinus in centre of
medullary cavity
Receives blood from medullary
sinusoids from end arterial loops
Diaphyseal vein
Periosteal veins
Metaphyseal veins
Epiphyseal veins
165. Articular surfaces
Head—a large rounded
elevation
Capitulum --a small rounded
elevation
Trochlea---pully shaped
articular surface
Condyles---a rounded knuckle
like articular area
166. Non articular surfaces
Processes
any prominent projection
Trochenter
Large blunt process
Tuberosities
Large rounded eminence
Tubercle
Small rounded eminence
Malleolus
A small rounded process
167. Epicondyles
A projection on or
above condyles
Spine
A short pointed
projection
Styloid process
A long pointed
projection
Hamulus
A hook like projection
168. Line
A slight ridge
Crest
A prominent border or
ridge
Fovea
A small shallow
depression
Notch
Indentation in edge of
bone
170. Nerve supply of bones
Periosteum at ends-----nerve supplying overlaying
muscle
Periosteum of subcutaneous bone-----nerve
supplying overlaying skin
Enter with nutrient artery-----supply bone tissue
Periosteum is most sensitive region of bone
Spongy bone more sensitive as compared to
compact bone
171. Rule of direction of nutrient foramen
Growing end of bone
Nutrient foramen directed against the growing end
Towards the elbow we go
Growing ends away from elbow
From the knee we flee
Growing ends towards the knee
172. QUEsTION
Which artery enter
through the nutient
foramina
Periosteal
Diaphysial*
metaphysial
Endosteal
cortical
SEQ’S
Briefly explain the
blood supply of
mature long bone?
174. Unused bones, such as in a paralyzed limb, atrophy
(decrease in size).
Bone may be absorbed, which occurs in the
mandible when teeth are extracted.
Bones hypertrophy (enlarge) when they support
increased weight for a long period.
175. Trauma to a bone break it.
Open fracture
Close fracture
Healing of fracture the broken ends must be
brought together, approximating their normal
position. This is called
reduction of a fracture.
Fracture of bone
176. Bone healing
surrounding fibroblasts
(connective tissue cells)
proliferate
secrete collagen
forms a collar of callus to hold
the bones together
Bone remodeling in fracture
area & callus calcifies.
callus resorbed and replaced
by bone.
After several months, little
evidence of the fracture
remains, especially in young
people
177. OsTEOPOROsIs
aging process
organic and inorganic components
of bone decrease
resulting in osteoporosis,
reduction in the quantity of bone,
atrophy of skeletal tissue
bones become brittle, lose their
elasticity, and fracture easily.
Bone scanning is an imaging
method used to assess normal and
diminished bone mass
178. Loss of arterial supply to an epiphysis or other
parts of a bone results in the death of bone
tissue—avascular necrosis.
In some fractures avascular necrosis may occur.
A number of clinical disorders of epiphyses in
children result from avascular necrosis of unknown
etiology (cause). These disorders are referred to as
osteochondroses.
Avascular Necrosis
179. many of breaks in bones are greenstick fractures
(incomplete breaks caused by bending of the bones).
Fractures in growing bones heal faster than those in
adult bones.
Greenstick fractures
180. Rickets is a softening of bones in children
due to deficiency or impaired metabolism of vitamin D ,
phosphorus or calcium
potentially leading to fractures and deformity.
Osteomalacia is a similar condition
occurring in adults, generally due to a deficiency
of vitamin D.
182. Dr AhmAD Ali Qureshi
(mBBs,GmC)
PharmoHub Pakistan
183.
184. The skeleton
The study of bones is termed
osteology.
The adult is composed of
approximately 206 bones. Each
bone is an organ of the skeletal
system. Start at 270 at birth,
decreases with fusion.
For the convenience of study, the
skeleton is divided into axial and
appendicular parts.
185. The axial skeleton
The axial skeleton
consists of 80 bones that
form the axis of the body
and which supports and
protects the organs of the
head, neck, and trunk.
Skull
Auditory ossicles
Hyoid bone
Vertebral column
Thoracic cage
186. The appendicular
skeleton
The appendicular skeleton is composed of
126 bones of the upper and lower limbs and
the bony girdles, which anchor the
appendages to the axial skeleton.
The shoulder girdle (the scapula
and clavicle)
The upper limb (the humerus,
ulna, radius and bones of the
hand)
The pelvic girdle (the hip bone)
The lower limb (the femur, tibia,
fibula and bones of the foot)
187. Functions of the skeleton
Biological functions
Mechanical functions
190. Classification of bones
Tubular bones
a) Long tubular bones
humerus,
radius, ulna,
femur,
tibia, fibula
b) Short tubular bones
metacarpal,
metatarsal bones and phalanges
191. Classification of bones
Spongy bones
a) Long spongy bones
sternum,
ribs, etc
b) Short spongy bones
carpal and tarsal bones
c) Sesamoid bones
knee-cap
pisiform bone, etc.
192. Classification of bones
Flat bones
Skull bones
Bones of the vault of the
skull
Girdle bones
The scapula
The hip bone, etc.
193. Classification of bones
Mixed bones
The vertebrae are mixed, or
irregular bones (their
bodies are referred to
spongy bones, but their
arches and processes are
referred to flat bones).
194. The Skull
The skull proTeCTs
The brain
Entrances to respiratory system
Entrance to digestive system
The skull ConTAins 22 Bones
8 cranial bones:
Form the braincase or cranium
14 facial bones:
Protect and support entrances to digestive and respiratory tracts
195. There Are eiGhT CrAniAl Bones, eACh wiTh A
uniQue shApe:
Frontal bone (1). This is the flat bone that makes up
your forehead. ...
Parietal bones (2). This a pair of flat bones located on
either side of your head, behind the frontal bone.
Temporal bones(2) ...
Occipital bone(1) ...
Sphenoid bone(1) ...
Ethmoid bone(1).
199. The mAjor suTures of The skull inCluDe The
followinG:
Metopic suture. This extends from the top of the head
down the middle of the forehead, toward the nose. ...
Coronal suture. This extends from ear to ear. ...
Sagittal suture. ...
Lambdoid suture.
200. CrAniAl fossA
3 basins that comprise the cranial floor or base
anterior fossa holds the frontal lobe of the brain
middle fossa holds the temporal lobes of the brain
posterior fossa contains the cerebellum
Swelling of the brain may force tissue through foramen
magnum resulting in death
8-19
201.
202.
203. A fonTAnelle (or fontanel) (colloquially, soft spot) is an
anatomical feature of the infant human skull comprising
any of the soft membranous gaps (sutures) between the
cranial bones that make up the calvaria of a fetus or an
infant.
The fonTAnelle allows the skull to deform during birth
to ease its passage through the birth canal and for expansion
of the brain after birth. The anterior fontanelle typically
closes between the ages of 12 and 18 months.
219. Dr AhmAD Ali Qureshi
(mBBs,GmC)
PharmoHub Pakistan
220.
221. At the end of lectures student should able to
Define arthrology
Define joints
Know the various types (classification) of
joints.
Classify the fixed joints
Classify slightly moveable joints
Classify highly moveable joints
223. JOINT/ ARTHROSES
A joint is the location at which two or more
Bones/ cartilage make contact.
They are constructed to allow movement
and provide mechanical support
224. Mobility of joints depends on following
factors..
The shape of articulating surfaces
Arrangement of various structure which unite
them
Stucture of joint is index of its functional
activity.i.e; movement
225.
226. Synarthroses or immovable/
Solid joint/ non cavitated joint
Amphiarthroses or slightly
movable
Diarthroses or freely movable/
Cavitated joint
227. The surfaces of the bones are in almost
direct contact
Fastened together by intervening
connective tissue or hyaline cartilage
and in which there is no appreciable
motion, as in the joints between the bones
of the skull
233. An immovable junction between two bones,
such as those of the skull. E.g…
In a SERRATE SUTURE, the edges are saw like
e.g Sagittal suture.
A DENTICULATE SUTURE has small tooth like
processes e.g Lambdoid suture.
In a SQUAMOUS SUTURE reciprocally bevelled
bone margins overlap each other e.g
Temporoparietal suture.
In a PLANE SUTURE there is simple apposition
of relatively flat bones e.g intermaxillary
suture.
234. A gomphosis is a fibrous mobile peg-and-
socket joint. The roots of the teeth (the
pegs) fit into their sockets in the mandible
and maxilla and are the only examples of this
type of joint.
235. The syndesmosis is a fibrous joint held together
by ligaments. It's located near the ankle joint,
between the tibia, or shinbone, and the distal
fibula, or outside leg bone. That's why it's also
called the distal tibiofibular syndesmosis. It's
actually made up of several ligament
236. TEMPORARY/ Primary (synchondroses)
They show intra cartilagenous method of
ossification. They remain in Hyaline cartilage
till completion of growth of bone.
Strong & immobile
Sternales
Epipysial plate
1st sternocostalis
237. Intra articular fibrocartilagenous disc
Slight movement due to deformation of disc
In median plane of body
Intermediate stage of
evolution
FIBROCARTILAGE WITH CAVITIES
WITHOUT CAVITY
238.
239.
240.
241.
242. Define suture? Classify various types of
sutures with one example .
Classify non- cavitated joints
243. Define sutures
Give example of serrate suture
What do you mean by syndesmosis?
How we differentiate between primary &
secondary cartilaginous joints
244. Diarthrosis. A freely mobile joint is classified
as a diarthrosis. These types
of joints include all synovial joints of the
body, which provide the majority of body
movements. Most diarthrotic joints are found
in the appendicular skeleton and thus give
the limbs a wide range of motion.
Lets have a look on Articular cartilage,
Fibrous Capsule, Ligaments, Synovial
membrane, Synovial fluid,Articular discs.
245. ArtiCulAr CArtilAGe : the bones of a synovial joint are
covered by this layer of Hyaline cartilage that lines the epiphyses
of joint end of bone with a smooth, slippery surface that does not
bind them together; articular cartilage functions to absorb shock
and reduce friction during movement.
FiBrous CApsule : the fibrous capsule, continuous with the
periosteum of articulating bones, surrounds the diarthrosis and
unites the articulating bones; the joint capsule consists of two
layers - (1) the oute rfibrous membrane that may contain
ligaments and (2) the inner synovial membrane that secretes the
lubricating, shock absorbing, and joint-nourishing synovial fluid;
the joint capsule is highly innervated, but without blood and
lymph vessels, and receives nutrition from the surrounding blood
supply via either diffusion (a slow process) or by convection, a far
more efficient process achieved through exercise.
liGAments : Ligaments are a type of connective tissue and are
tough, fibrous and slightly elastic. They connect bone to bone and
help keep the joint together. They stabilise the joints during
movement and prevent dislocation by restricting actions outside
the normal joint range.
246. A synoviAl memBrAne (or synovium) is the soft tissue found
between the articular capsule (joint capsule) and the joint cavity
of synovial joints.
synoviAl FluiD is the clear, viscid, lubricating fluid secreted
by synovial membranes. The morphology of synovial
membranes may vary, but it often consists of two layers. Volume
of synovial fluid is 0.5 ml in knees.
Egg albumin like fluid present in joint cavities, bursa and tendon
sheath
PH- alkaline, turns to acidic
0.5ml volume
Hyluronic acid
Proteins
Cells – macrophages, lymphocytes, neutrophils, synovial cell
ArtiCulAr DisC - the fibrocartilage pads between opposing
surfaces in a joint
256. OBJECTIVES
At the end of lecture you should able to;
Classify various types of synovial joints.
Identify the synovial joints according to
the structures.
Classify joints according to their
articulating surfaces.
Classify joints according to complexity of
organization
258. I. PLANE JOINT/ ANTHROIDAL
JOINT
• Bone surfaces are slightly curved/ almost flat.
• Side to side movement/ gliding only
• Rotation prevented by
ligaments
• Examples:
- Intercarpal
- intertarsal joints
- sternoclavicular joint
259. HINGE JOINT/ GINGLYMOID
• Convex surface of bone fits in concave surface of
2nd bone
• like a door hinge
• Examples:
- Knee, elbow,
- interphalangeal
Uniaxial
• Movements produced:
- flexion
- Extension
- To and fro
260. PIVOT / ROTATORY/ TROCHOID
JOINT
• Rounded surface of bone articulates with the ring
formed by the 2nd bone & ligament
Monoaxial
• since it only allows rotation around longitudinal axis
• Examples:
Pivot rotates inside
stationary osseofibrous ring
proximal radioulnar
Ring rotates around stationary
pivot
atlanto-axial joint
262. BICONDYLAR JOINT
Two convex surfaces articulate with two
concave surfaces
Uniaxial
Two subtypes
Both condyles present on single capsule
◦ Knee joint
Both condyles lie at a distance and each
having a separate capsule
◦ Temporomandibular joint
263. SADDLE/ SELLER/ RECEPTIVE
• One bone saddle-shaped, other bone fits like a
person riding on the saddle
Biaxial
• Examples:
- Trapezium of carpus and metacarple of
thumb
264. BALL & SOCKET/ SPHEROIDAL
• Ball fitting into a cup-like depression
• Multiaxial
- flexion/extension
- abduction/adduction
- rotation
• Examples:
- shoulder joint
- hip joint
265. ELLIPSOID
Oval convax surface fix into elliptical
concavity
Biaxial
Example
Wrist joint
270. DEPENDING UPON COMPLEXITY
OF ORGANIzATION
SIMPLE :When two bones participating
COMPOUND : More than two bones
COMPLEX : Intra articular disc or menisci
present
275. NERVE SUPPLY OF JOINTS
(HILTON’S LAw)
Hilton’s Law; joints are innervated with
the nerve of supply to the muscles, which
act on them
Motor nerve to the muscle acting on
joints tend to give branch to
Capsule of that joint
Skin covering that joint
316. Muscle cONTracTiON
TONIC (normal muscle tone)
PHASIC (It is of 2 types i.e ISOTONIC and
ISOMETRIC )
Isotonic (Length changes , tension same)
Isometric ( Length same , tension changes )
Isotonic is further of two types i.e CONCENTRIC
and ECCENTRIC.
REFLEXIVE (spontaneous movement due to O2 or
CO2 concentrations e.g knee reflex)
317. cONceNTric MOveMeNT…
Movement occurs by
shortening of muscles.
Eg biceps brachi.
ecceNTric MOveMeNT…
Movement occurs by
contraction of muscles.
Eg Lowering a weight
during a shoulder press.
The downward motion of
squatting.
The downward motion of a
push-up.
Lowering the body during a
crunch.
Lowering the body during a
pull-up.
324. Left:
Abduction –
moving the
leg away
from the
midline
Above –
Adduction-
moving
toward the
midline
Right:
Circumduction: cone-
shaped movement,
proximal end doesn’t
move, while distal end
moves in a circle.
326. D U R I N G F O R E A R M F L EX I O N, F O R E X A MP L E L I F T I NG
A C U P , A MU S C L E C A L L ED T H E B I C E P S B R A C HI I I S
T H E PR I M E MO V E R . B E C A U S E I T C A N B E A S S I S T ED
B Y T H E B R A C H I A L I S , T HE B R A C H I A L I S I S C A L L E D
A S Y N E R G I S T I N T H I S A C T I O N ( F I G U R E 1 1 . 1 . 1 ) .
A S Y N E R G I S T C A N A L S O B E A F I X A T O R T H A T
S T A B I L I Z E S T HE M U S C L E' S O R I G I N .
327. DisOrDers relaTiNG TO The Muscular
sysTeM
Muscular Dystrophy: inherited, muscle enlarge due
to increased fat and connective tissue, but fibers
degenerate and atrophy
Duchenne MD: lacking a protein to maintain the
sarcolemma
Myasthemia Gravis: progressive weakness due to a
shortage of acetylcholine receptors
335. the sKin
• The integumentary system consists of the skin
(cutaneous membrane) and its accessory organs.
• The skin is composed of three layers of tissue: the
outer epidermis (made of stratified squamous
epithelium ), the middle dermis (made of fibrous
connective tissue ), and the inner subcutaneous layer
or hypodermis (made of adipose tissue and loose
connective tissue).
• Accessory organs include the hair (hair root and hair
shaft) , hair follicle , pili arrector muscle, sebaceous
gland , sudoriferous gland , nails , and mammary
gland.
ebneshahidi
337. FunCtiOns OF the inteGumentAry
ssystemystem
1. protection
a) chemical factors in the skin:
Sebum (or oil) from the sebaceous glands is slightly
acidic, retarding bacterial colonization on the skin
surface.
Sweat from the sudoriferous glands is slightly
hypertonic and can flush off most bacteria on the skin
surface.
Melanin (skin pigment ) from melonocytes avoids
excessive ultraviolet radiation from penetrating the
skin layers . ebneshahidi
338. b) physical factors in the skin:
Stratified squamous epithelium in the epidermis
layer provides a large number of layers of cells,
preventing most bacteria invasion.
Keratinized cells in the stratum corneum layer of
the epidermis provides a physical barrier against
most invasion.
c) biological factor in the skin:
White blood cells such as macrophages destroy
most invaded bacteria and other foreign
substances.
ebneshahidi
339. 2. Excretion
waste materials such as ammonia , urea , and excessive
salt are eliminated from sweating .
3. Body temperature regulation
Sweating by the sweat glands promotes evaporation ,
resulting in a loss of excessive body heat.
Vasoconstriction by arterioles (small arteries ) in the
dermis layer provides a smaller surface area in the
blood vessels, resulting in less heat loss .
Vasodilatation by arterioles in the dermis layer
provides a larger surface area in the blood vessels ,
resulting in greater heat loss .
ebneshahidi
340. 4. Cutaneous sensation
Nerve receptors in the dermis layers detect
sensations such as heat, cold, pain, pressure, and
touch, allowing the body to be aware of these
stimuli.
5. Vitamin D synthesis
Ultraviolet radiation in the sunlight activates a
series of chemical reactions in the epidermis
layer, resulting in the synthesis of vitamin D
from the modification of cholesterol for the
absorption of calcium.
ebneshahidi
341. FunCtiOns OF the sKin
• maintains homeostasis.
• prevents the body from the penetration of harmful
substances.
• Prevents water loss(desiccation) .
• help to regulate body temperature .
• contains nerve receptors for various sensations .
• synthesizes chemical substances such as keratin,
melanin, and vitamin D.
• excretes waste materials such as ammonia , urea , and
salts.
• produces skin pigment (melanin) in the epidermis and
hair to avoid excessive penetration of UV radiation .
ebneshahidi
342. ePiDermis
• Being made of stratified squamous epithelium , there is no blood
vessels to supply nutrients to its cells.
• Nutrients from the arterioles in the dermis layer diffuse upward
into the epidermis layer, especially to the stratum basale and
spinosum layers.
• Cuboidal cells at the stratum basale (stratum germinativum)
layer receive most of the nourishment . These cells reproduce
rapidly using mitosis . New daughter cells will be pushed upward
into higher layers , and they become flattened as they move
upward .
• Squamous cells moving upward in the epidermis receive less and
less nutrients as diffusion distance increases. By the time they
form stratum corneum , the cells are dead and will be shed off
from the skin .
ebneshahidi
343. • Epidermal cells in stratum granulosum and stratum corneum
undergo “keratinization " to produce a protein called keratin,
allowing these cells to be tough and waterproof. These cells are
now called " karatinocytes " where they develop desmosomes
between the cells and allow the epidermis to become a stronger
physical barrier .
• F i v e layer of cells are found in the epidermis of the body
stratum basale , stratum spinosum , stratum granulosum , and
stratum corneum. In the palms and soles , an extra layer beneath
stratum coruneum is formed , called stratum Lucidum.
• Specialized cells called melanocytes in the stratum basale layer
produce the skin pigment, melanin. The number of melanocytes
and the amount of melanin production are genetically inherited .
ebneshahidi
345. lAyers OF ePiDermis
The 5 Layers of Your Skin
Stratum Basale or Basal Layer.The deepest layer of the
epidermis is called the stratum basale, sometimes called the
stratum germinativum. ...
Stratum Spinosum or the Spiny layer.This layer gives
the epidermis its strength. ...
Stratum Granulosum or the Granular Layer. ...
Stratum Lucidum. ...
Stratum Corneum.
NEMONIC : (CLG-SB)
346.
347.
348. Dermis
• made of fibrous connective tissue that contains
arterioles for supplying nutrients (i.e. oxygen ,
glucose , water , and ions ) to its structures and to the
epidermis .
• also contains pilo-errector muscles (made of skeletal
muscle, under involuntary control) to wrinkle the skin
and erect the hairs .
• contains nerves and nerve receptors to detect the
sensations of heat, cold, pressure, touch, and pain .
• also contains hair follicles to develop the hair .
• contains sebaceous gland to secrete sebum onto skin
surface, and sudoriferous glands to secrete sweat.
ebneshahidi
349. hyPODermis
– Made of adipose tissue and loose connective
tissue.
– Collagen and elastic fibers in the loose connective
tissue are continuous with the fibers in the dermis
layer.
– Adipose tissue serves as a heat insulator against
cold climate and as a fat storage.
– Loose connective tissue allows the skin to be
bound with underlying muscles.
– Also contains large blood vessels (arteries and
veins).
ebneshahidi
352. ACCessOry struCtures OF the sKin
1. Hair
– produced by epithelial cells at the hair papilla .
– made of keratinized cells .
– consists two regions: hair root (in the hair follicle
, embedded in the dermis layer), and hair shaft
(protruded through the epidermis to the outside).
– Hair pigment (melanin) is produced by
melonocyets in hair papilla .
– Hair growth is affected by nutrition and hormones
(i.e. testosterone).
ebneshahidi
355. 2. Pili erreCtOr musCle
• made of skeletal muscle ,
but under involuntary
control.
• attached to each hair
follicle, for erecting the
hair.
• situations such as extreme
emotions or extreme
temperatures can activate
its involuntary contraction
, resulting in hair erection
or skin wrinkling.
ebneshahidi
356. 3. seBACeOus GlAnD
• Oil gland that is made of
modified cuboidal epithelium.
• Occurs all over the body
except in the palm and sole.
• Attached to each hair follicle,
so that sebum can be secreted
into the hair root and diffuse
upward .
• Sebum helps the skin and hair
to be waterproof, and retards
bacterial growth on skin
surface(due to its acidity).
ebneshahidi
357. 4. suDOriFerOus GlAnD
• sweat gland that secretes
sweat to promote
evaporation.
• found all over the body
except the lips, nipples,
and external genitalia.
• referred to as "tubular
gland" where it is a long
tubule coiled in the
dermis layer , and uses a
long duct to release
sweat onto skin surface
through a pore.
ebneshahidi
358. 5. nAils
• scale like
modification of
epithelial cells in the
epidermis.
• made of keratin.
• Protect ends of fingers
and toes and prevent
over sensitization of
the never receptors in
extremities.
• Growing cells are
derived form a region
at base of nail called
"lunula".
ebneshahidi
359.
360. Burns
• First degree burns: only the epidermis is
damaged with redness and swelling .
• Second degree burns: epidermis & upper
region of dermis is involved. There is Redness,
swelling, and blisters.
• Third degree burns: all layers of skin burned
(most severe). Skin graft is necessary to repair.
Skin looks cherry red or blacken
ebneshahidi
363. sKin CAnCer
• Most skin tumors are benign
• Cause of cancer is unknown, but probably due to
overexposure to ultraviolet radiation in the sunlight .
• Three main types of skin cancer :
• Basal cell carcinoma
• The most common type of skin tumor; usually benign.
• Cells of stratum basale are affected , as a result they
cannot form keratin and begin to invade into the
dermis.
• Surgical removal (given that early detection is done)
is 99% successful .
ebneshahidi
364. sQuAmOus Cell CArCinOmA
• arises form keratinocytes in stratum spinosum .
• mostly in the scalp , ears , or hands.
• grows and migrates rapidly.
• early detection is critical for successful treatment.
Malignant Melanoma – most dangerous
• cancer of the melanocyets in stratum basale.
• only 5% of all skin cancer , but the frequency is increasing.
• grow and migrates extremely rapidly .
• usually deadly.
Note: To avoid these skin tumors , it is advised that we should stay
away from the sun during its most intense period: from 10 am to 2
pm . ebneshahidi
365. CliniCAl terms
• Albinism – inherited, melanocytes do not produce melanin.
• Boils and carbuncles – inflammation of hair follicles and
sebaceous glands, infection spread to dermis .
• Contact dermatitis – itching and redness and swelling forming
blisters. It is caused by chemical burns.
• Psoriasis : characterized by reddened epidermal lesions
covered by dry silvery scales.
• Roscea : redness of skin around eyes and nose accompanied by
rash – like lesions, It gets worse with alcohol , hot H2O, and
spicy food .
• Vitiligo : skin pigmentation disorder caused by loss of melan-
octyts and uneven dispersal of melanin (unpigmented skin
surrounded by normally pigmented areas) .
ebneshahidi
376. OUTLINE
Introduction to the Digestive System
Divisions
Alimentary Canal
Accessory Organs
Organs
Location
Functions
THE ROLE OF COMPUTERS IN MEDICAL PHYSICS. VICTOR EKPO. CMUL - LAGOS
377. INTRODUCTION
The Digestive System is a group of
organs working together to
convert food into energy and
basic nutrients to feed/nourish the
body.
ANATOMY OF THE DIGESTIVE SYSTEM. VICTOR EKPO. CMUL - LAGOS
378. Fig: Anterior view of the Digestive System
ANATOMY OF THE DIGESTIVE SYSTEM. VICTOR EKPO. CMUL - LAGOS
379. DIVISIONS
The Digestive System consists of 2 parts: the
Alimentary Canal, and their Accessory Organs.
The alimentary canal is also called the digestive tract
OR gastrointestinal tract GIT (though GIT is
technically stomach + intestines only).
The alimentary canal is the long tube that runs from
the mouth through to the anus.
ANATOMY OF THE DIGESTIVE SYSTEM. VICTOR EKPO. CMUL - LAGOS
380. ALIMENTARY CANAL
The main parts of the Alimentary Canal are:
* Mouth (Oral cavity)
* Pharynx (Throat) * Oesophagus (also esophagus)
* Stomach * Small intestine
* Large intestine * Rectum and anal canal (anus).
381.
382. ACCESSory orGAnS
The Accessory Organs include other organs (mainly glands) that aid
digestion. These include:
Tongue, salivary glands and tonsils (for mouth)
Tubular mucous glands (for pharynx, oesophagus, large intestine)
Liver, Gallbladder, and Pancreas (for small intestine);
Epiglottis: which tips posteriorly at the pharynx to prevent food
from entering the larynx/respiratory tract.
Mesentery* (newly discovered organ that helps hold the intestines
to the posterior abdominal cavity).
383. Digestion starts in the mouth, where food is chewed and
mixed with saliva to form a bolus.
The bolus produced is then swallowed down the pharynx and
oesophagus via peristaltic contractions and into the stomach.
In the stomach, it is mixed with gastric juice to form a
semifluid substance called chyme, then moved to the
duodenum (small intestine).
Most of the digestion takes place in the stomach and
duodenum of the small intestine.
Water and some minerals are reabsorbed in the colon of the
large intestine. The chyme is turned to faeces. The faeces is
defecated from the anus via the rectum.
ANATOMY OF THE DIGESTIVE SYSTEM. VICTOR EKPO. CMUL - LAGOS
385. ABDomInAl SurfACE AnAtomy CAn BE DESCrIBED whEn VIEwED from In
front of thE ABDomEn In 2 wAyS: DIVIDED Into 9 rEGIonS By two VErtICAl
AnD two horIzontAl ImAGInAry PlAnES. DIVIDED Into 4 QuADrAntS By
SInGlE VErtICAl AnD horIzontAl ImAGInAry PlAnES.
386. MOUTH (ORAL CAVITY)
The mouth or oral cavity is
bounded by muscles and bones:
Anteriorly – by the lips
Posteriorly – it is continuous with
the oropharynx (part of pharynx)
Laterally – by the muscles of the
cheeks
Superiorly – by the bony hard
palate and muscular soft palate
Inferiorly – by the muscular tongue
and the soft tissues of the floor of
the mouth.
387. SAlIVAry GlAnDS
Most animals have three major pairs of salivary glands
and hundreds of minor salivary that differ in the type of
secretion they produce:
1-Parotid glands produce a serous, watery secretion.
2-Submaxillary (mandibular) glands produce a mixed
serous and mucous secretion.
3-Sublingual glands secrete a saliva that is predominantly
mucous in character.
388. TONGUE
The tongue is a large, muscular organ
that occupies most of the oral cavity.
It is attached by its base to the hyoid
bone, and by thin fold of tissue called the
frenulum, to the floor of the mouth.
A groove called the terminal sulcus
divides the tongue into two parts.
• Anterior: covered by papillae (contains
some taste buds).
• Posterior: contains few small glands
and a large amount of lymphoid tissue,
the lingual tonsil. Fig: Dorsal surface of tongue & tonsils
389. tonGuE PAPPIlAE
Papillae are the tiny raised protrusions on the
tongue that contain taste buds. The three types of
papillae are:
1-Fungiform (mushroom like)
2-Filiform (filum - thread like)
3-Crcumvallate.
4-Folliate
Except for the filiform, these papillae allow us to
differentiate between sweet, salty, bitter, sour, and
umami (or savory) flavors.
390. TEETH (SKELETAL) The teeth are embedded in
the mandible and maxilla
bones.
Movement of the mandible
(lower jaw) allows chewing.
The mandible is the only
moveable bone in the jaw.
There are 20 temporary teeth.
Later, 32 permanent teeth
replace the 20.
There are incisors (8), canines
(4), premolars (8), and molars
(12).
Fig: Skeletal system of the mouth
391. PHARYNX
It connects to the oral cavity anteriorly, and is continuous
with the oesophagus. Food passes from the oral cavity into
the pharynx then to the oesophagus below it.
The pharynx consists of three parts:
nasopharynx,
oropharynx, and the
laryngopharynx.
It prevents food from entering the nasal cavity (by the soft
palate) and the lower respiratory tract (by the epiglottis).
393. OESOPHAGUS
Also called gullet or esophagus, it
is an organ through which food
passes from the pharynx to the
stomach, aided by peristaltic
contractions, of its musculature.
It is about 25 cm long and 2 cm in
diameter, and lies in the median
plane (mediasternum) in the
thorax, anterior to the spinal
column, but posterior to the
trachea.
394. CONSTRICTIONS OF THE OESOPHAGUS
The oesophagus follows the curvature of the
vertebral column.
It also has 3 constrictions (narrowing), where
adjacent structures produce impressions:
1. Cervical Constriction (Upper Oesophageal
Sphincter) – where Pharynx meets
Oesophagus.
2. Thoracic (Broncho-Aortic) Constriction –
where it is first crossed by arch of aorta.
3. Diaphragmatic Constriction: where it
passes through the oesophageal hiatus of
the diaphragm at t10, before entering the
stomach.
395.
396.
397. OESOPHAGUS (contd.)
Immediately the oesophagus has
passed through the esophageal
hiatus (opening) of the diaphragm, it
curves upwards before opening into
the stomach.
This sharp angle, as well as the
sphincters at each end (e.g. cardiac
sphincter), prevents the regurgitation
(backflow) of gastric contents into the
oesophagus.
The oesophagus has thick walls consisting of the four layers/tunics common
to the digestive tract: mucosa (innermost), submucosa, muscularis, and
serosa/adventitia (outermost).
399. LOCATION OF THE STOMACH
It is the enlarged hollow part of
the digestive tract specialized in
the accumulation of ingested
food, and also acts as food
blender.
It is located between the
oesophagus and the small
intestine.
It is located in the epigastric,
umbilical & left hypochondriac
regions of the abdominal cavity. Gastroenterology deals with the study of
diseases of the stomach and intestines
and their associated organs
400. PARTS OF THE STOMACH
The stomach has four (4) parts:
Cardiac
Fundus
Body
Pylorus
The stomach is continuous with the
oesophagus at the Cardiac Sphincter,
and with the Duodenum at the Pyloric
Sphincter.
The Pyloric Sphincter guards the opening between the stomach and the
duodenum. When the stomach is inactive, the pyloric sphincter is relaxed and
open, and when the stomach contains food, the sphincter is closed.
401. CEllS In StomACh
Four different types of cells make up the gastric
glands:
1-Mucous cells … secrete an alkaline mucus that
protects the epithelium against shear stress and acid.
2-Parietal cells … secrete hydrochloric acid and
INTRINSIC FACTOR.
3-Chief cells … secrete pepsin, a proteolytic enzyme.
4-G cells … which are endocrine cells that synthesize
and secrete the hormone gastrin.
402.
403. IntrInSIC fACtor
Intrinsic factor is a glycoprotein secreted by
parietal (humans) or chief (rodents) cells of the
gastric mucosa. In humans, it has an important role
in the absorption of vitamin B12 (cobalamin) in the
intestine, and failure to produce or utilize intrinsic
factor results in the condition pernicious anemia. A
small amount of vitamin B12 is absorbed by passive
diffusion without intrinsic factor.
404.
405. SMALL INTESTINE
The small intestine is the part of the
GIT between the stomach and large
intestine.
The small intestine is continuous
with the stomach at the Pyloric
Sphincter and leads into the large
intestine at the ileocaecal valve.
It is about 2.75 – 10.49 m long. For
an average person, it is 3-5m.
It lies in the abdominal cavity
surrounded by the large intestine.
406. PARTS OF SMALL INTESTINE
There are 3 parts of the Small Intestine:
Duodenum: First, shortest, widest and
most fixed part (0.25m long).
Jejunum: This is the middle section of
the small intestine (about 2.5m long) –
about 2/5th
Ileum: Joins the large intestine at the
Ileocecal Junction
(3- 3.5m long) – about 3/5th
The mesentery, a double layer of peritoneum, supports and attaches the
jejunum and ileum (small intestine) to the posterior abdominal wall.
407.
408. PERITONEUM & MESENTERY
The peritoneum (yellow portion) is the largest
serous membrane of the body. It is a closed sac,
containing a small amount of serous fluid, within
the abdominal cavity.
It provides attachment to organs of the GIT, and
acts as a physical barrier to localize spread of
infection.
It invaginates the stomach, small intestine, liver,
pancreas, kidney, spleen, and other pelvic
organs.
The mesentery associated with the small
Intestine is sometimes called the Mesentery Proper. There are mesenteries of
other parts, e.g. of the colon: transverse mesocolon.
409. The structures within the intraperitoneal space are called "intraperitoneal" (e.g., the stomach
and intestines),
the structures in the abdominal cavity that are located behind the intraperitoneal space are
called "retroperitoneal" (e.g., the kidneys).
The term subperitoneal refers to tissue that is deep to the peritoneum and includes the
extraperitoneal space, the ligaments and the mesenteries and their suspended organs . Organs
whose surfaces are covered by peritoneum are therefore subperitoneal.
410.
411. Intraperitoneal Structures…
Intraperitoneal organs include the stomach, the first five centimeters and
the fourth part of the the duodenum, the jejunum, the ileum, the cecum,
the appendix, the transverse colon, the sigmoid colon, and the upper third
of the rectum.
Retroperitoneal Organs…
S = Suprarenal (adrenal) Glands.
A = Aorta/IVC.
D =Duodenum (except the proximal 2cm, the duodenal cap)
P = Pancreas (except the tail)
U = Ureters.
C = Colon (ascending and descending parts)
K = Kidneys.
E = (O)esophagus.
R = Rectum
412. LIVER & GALL BLADDER
The liver is an accessory digestive gland,
and largest internal organ.
It is involved in the:
• Synthesis of glucose from amino acid
• Breaking down of carbohydrates
• Synthesis of cholesterol
• Production of fat, through lipogenesis.
• Production of bile.
The bile produced is stored in the gall bladder, and secreted to the small
intestine during food digestion. The gallbladder is a saclike structure on the
inferior surface of the liver that is about 8 cm long and 4 cm wide.
413. PANCREAS
The pancreas is a pale grey
gland weighing about 60g. It is
about 12–15 cm long and is
situated in the
epigastric and left
hypochondriac regions of the
abdominal cavity.
It consists of a broad head, a
body and a narrow tail.
It secrets pancreatic juice
(exocrine pancreas), and insulin
and glucagon (endocrine
pancreas).
414. Your pancreas plays a big role in digestion.
It is located inside your abdomen, just
behind your stomach. It's about the size of
your hand. During digestion, your
pancreas makes pancreatic juices called
enzymes. These enzymes break down
sugars, fats, and starches
It's possible to live without a pancreas. But when the entire pancreas is removed, people are
left without the cells that make insulin and other hormones that help maintain safe blood
sugar levels. These people develop DIABETES (DM TYPE 2), which can be hard to manage
because they are totally dependent on insulin shots. There are a few things you must
completely avoid, such as alcohol and fried/greasy/high fat foods (such as creamy sauces,
fast food, full fat meat and dairy, and anything fried). These foods can cause your pancreas to
release more enzymes at once than it normally would, leading to an attack
415.
416. LARGE INTESTINE
The Large Intestine meets the Small
Intestine at the ileocaecal valve,
then continues to the anal canal.
It is about 1.5m long and 6.5cm
wide (Small Intestine: 2.5cm).
It consists of the
Cecum (proximal end),
Appendix
Colon (ascending, descending,
sigmoid, transverse),
Rectum,
Anal canal (distal end)
Fig: Parts of the Large Intestine
417. SPECIAl StruCturES of lArGE IntEStInE
Three features are unique to the large intestine…
Teniae coli
Haustra
Epiploic appendages
The teniae coli are three bands of smooth muscle that make up the longitudinal
muscle layer of the muscularis of the large intestine, except at its terminal end.
The haustra refer to the small segmented pouches of bowel separated by the
haustral folds. They are formed by circumferential contraction of the inner
muscular layer of the colon. Epiploic appendages are peritoneal structures that
arise from the outer serosal surface of the bowel wall towards the peritoneal
pouch. They are filled with adipose tissue and contain a vascular
stalk. Epiploic appendagitis is a rare cause of acute lower abdominal pain.
418.
419. funCtIonS of thE DIGEStIVE
SyStEm
Ingestion,
Mastication,
Propulsion,
Mixing,
Secretion,
Digestion,
Absorption, and
Elimination.
420. ORGAN FUNCTIONS
Ingestion, T
aste, Mastication, Digestion,
Swallowing, Communication, Protection.
Mouth
Swallowing, Breathing, Protection
Propulsion, Protection.
Pharynx
Oesophagus
Storage, Digestion, Absorption, Mixing and
Propulsion, Protection.
Stomach
Neutralization, Digestion, Absorption, Mixing and
Propulsion, Excretion, Protection.
Absorption, Storage, Mixing and Propulsion,
Protection, Excretion.
Small Intestine
Large Intestine
429. LIVER
The liver is
located in the upper
right-hand portion
of the abdominal
cavity, beneath the
diaphragm, and on
top of the stomach,
right kidney, and
intestines. Shaped
like a cone, the liver
is a dark reddish-
brown organ that
weighs about 3
pounds.
430.
431. PORTA HEPATIS
The porta hepatis is a deep fissure in the inferior
surface of the liver through which all the neurovascular
structures (except hepatic veins) and hepatic ducts enter or
leave the liver 1. It runs in the hepatoduodenal ligament
and contains: right and left hepatic ducts. right and left
branches of hepatic artery. CONTENTS :
The portal vein (RT and LT branches)
The hepatic artery (RT and LT branches)
The hepatic ducts (RT and LT branches)
The hepatic nervous plexus
The lymphatic vessels
432.
433. BARE AREA OF LIVER
The bare area of the liver (nonperitoneal area) is a
large triangular area on the diaphragmatic surface
of the liver, devoid of peritoneal covering. It is
attached directly to the diaphragm by loose connective
tissue.
The bare area of the liver is clinically important
because of the portacaval anastomosis and it
represents a site where infection can spread from the
abdominal cavity to the thoracic cavity.
434.
435. INTRODUCTION…
When the liver cells secrete bile, it is collected by a
system of ducts that flow from the liver through the
right and left hepatic ducts. These ducts ultimately
drain into the common hepatic duct. The common
hepatic duct then joins with the cystic duct from the
gallbladder to form the common bile duct.
The organs and ducts that make and store bile (a fluid
made by the liver that helps digest fat), and release it
into the small intestine. The biliary system
includes the gallbladder and bile ducts inside and
outside the liver. Also called biliary tract.
436. BILE CANALICULI…
Bile canaliculi are tiny, 1- to 2-μm wide tissue spaces
formed by the apical membranes of adjacent
hepatocytes.
Bile canaliculi also known as bile capillaries are thin
tubes that receive bile secreted by hepatocytes. The
bile canaliculi eventually merge and form bile
ductules. The bile passes through canaliculi to the
hepatic bile ducts and then into the common hepatic
duct which drains directly into the duodenum.
437.
438. BILE…
Bile is a fluid that is made and released by the liver and stored in
the gallbladder. Bile helps with digestion. It breaks down fats into
fatty acids, which can be taken into the body by the digestive tract. ...
Bile acids (also called bile salts) Bilirubin (a breakdown product or red
blood cells)
Hepatocytes produce bile by secreting conjugated bilirubin, bile
salts, cholesterol, phospholipids, proteins, ions, and water into their
canaliculi (thin tubules between adjacent hepatocytes that eventually
join to form bile ducts
Bile is usually yellow or green.
Bile is secreted into the small intestine where it has two effects:
it neutralises the acid - providing the alkaline conditions needed in the
small intestine.
it emulsifies fats - providing a larger surface area over which the lipase
enzymes can work.
439. COMPONENTS OF BILIARY SYSTEM
The biliary system consists of the organs and ducts
(bile ducts, gallbladder, and associated
structures) that are involved in the production and
transportation of bile.
From the right and left hepatic ducts, bile then flows
into the common hepatic duct. The common hepatic
duct joins the cystic duct, where the bile then flows.
The cystic duct is connected to the gallbladder. Bile
flows from the cystic duct into the common bile duct.
440. EXTRAHEPATIC BILIARY
SYSTEM
RT hepatic duct
LT hepatic duct
Common hepatic duct
Cystic duct
Common bile duct
Gallblader
441.
442.
443. PORTAL TRIAD
The portal triad is a
TRIANGULAR area at the
liver named after its
triangular shape and its
three major
components: the hepatic
artery, the hepatic portal
vein, and the hepatic
ducts, or bile ducts. The
term, however, can be
considered a misnomer,
since it contains other
structures as well.
444.
445.
446.
447.
448.
449. BILIARY TREE…
The biliary tree is a system of vessels that directs
these secretions from the liver, gallbladder and
pancreas through a series of ducts into the
duodenum
The ampulla of Vater is a small opening that enters
into the first portion of the small intestine, known
as the duodenum. The ampulla of Vater is the spot
where the pancreatic and bile ducts release their
secretions into the intestines.
450.
451. CALLOT`S TRIANGLE
The triangle of Calot is an important landmark whose
boundaries include the common hepatic duct medially,
the cystic duct laterally, and the inferior edge of the
liver superiorly.
SIGNIFICANCE :
This triangular space is dissected to allow the surgeon
to identify, divide, and ligate the cystic duct and artery.
452.
453. HEPATOCYSTIC TRIANGLE
SUPERIORLY… the inferior border of
liver.
LATERALY… the cystic duct and the neck
of the gallbladder.
MEDIALLY… the common hepatic duct.
454.
455. Symptoms of possible biliary
disease
Jaundice (yellowing of the skin and whites of the eyes)
Abdominal pain, especially in the upper right side of
the abdomen under the rib cage.
Nausea or vomiting.
Loss of appetite, which may result in weight loss.
Fatigue.
Fever or chills.
Itching.
Light brown urine.
456. DISEASES OF BILIARY SYSTEM
Gallstones and Cholecystitis
Gallbladder Tumors
Choledocholithiasis
Acute cholangitis
457. Gallstones and Cholecystitis
Gallbladder stones are an extremely common disorder
and are usually asymptomatic. Some patients
experience biliary colic, an intermittent and often
severe pain in the epigastrium or right upper quadrant,
and at times between the scapula because of
temporary obstruction of the cystic duct with a
gallstone. If the cystic duct obstruction persists, the
gallbladder becomes inflamed and the patient
develops cholecystitis, an acute inflammation and
infection of the gallbladder.
458.
459. ACUTE CHOLANGITIS…
CHOLANGIOCYTES are the epithelial cells of the
bile duct.
Acute cholangitis is bacterial infection of the extra-
hepatic biliary system. As it is caused by gallstones
blocking the common bile duct in most of the
cases, its prevalence is greater in ethnicities with high
prevalence of gallstones.
465. GENERAl STRUCTURE AND FUNCTIoNS
oF ThE URINARY SYSTEM
● The urinary system, also known as the renal system
● The urinary system refers to the structures that produce and conduct
urine to the point of excretion.
■ Organs of the Urinary System:
■ Kidneys (2)
■ Ureters (2)
■ Urinary Bladder
■ Urethra
■ Primary organs: kidneys
■ filter waste products from the bloodstream
■ convert the filtrate into urine.
■ The Urinary Tract:
■ Includes:
■ ureters
■ urinary bladder
■ urethra
They transport the urine out of the body.
466.
467. 27-7
KIDNEYS: GRoSS AND SECTIoNAl
ANAToMY
■ Retroperitoneal
■ Anterior surface covered with peritoneum
■ Posterior surface against posterior abdominal
wall
■ Superior pole: T-12
■ Inferior pole: L-3
■ Right kidney ~ 2cm lower than left due to
left lobe of liver.
■ Adrenal glands on superior pole
472. 27-12
KIDNEYS: GRoSS AND SECTIoNAl
ANAToMY
■ Sectioned on a coronal plane:
■ Renal Cortex
■ Renal Medulla
■ Divided into renal pyramids
■ 8 to 15 per kidney
■ Base against cortex
■ Apex called renal papilla
473. 27-13
KIDNEYS: GRoSS AND SECTIoNAl
ANAToMY
■ Minor calyx:
■ Funnel shaped
■ Receives renal papilla
■ 8 to 15 per kidney, one per pyramid
■ Major calyx
■ Fusion of minor calyces
■ 2 to 3 per kidney
■ Major calyces merge to form renal pelvis
■ Renal Lobe
■ Pyramid plus some cortical tissue
■ 8 to 15 per kidney