Physiology is the science of life

1. 1
Introduction
To physiology
(1)
Dr. Ramadan Saad
PHSL222Principles of Physiology

2. Objectives
● Define physiology.
● Describe the levels of organisation of an organism.
● Provide an orientation to the subject of human physiology
● Describe briefly the basic structure and state the
function of the different body tissues.
● Discuss briefly the different levels of organization
starting from the cell to body systems giving examples at
each level.

3. What is physiology ?
Definitions
Physio + ology
Physio: Nature
Ology: science or study of
Physiology: the science
dealing with the way a
normal organism and their
body parts function.
How it is
related to
medicine?
Because the understanding of
physiology is essential for the
study and practice of medicine
Cellular physiology Systems physiology
Is the study of cellular
components that primarily
determines organ function.
Is the study of coordinated
and networked processes
that determines the whole
body function and adaptation
to change .
Examples:
Golgi apparatus —> Packaging,
sorting… of proteins.
Respiratory system, cardiovascular
system… Thus: different systems
work in harmony to provide the
Homeostasis.
Types of physiology:
Many diseases can be viewed as
physiology “ gone wrong “
PATHOPHYSIOLOGY
The Difference between
anatomy and physiology:
Anatomy : the structure
Physiology :the function
(It is a cornerstone to medicine )

4. Distinguish between Process &Function
Process Function
• How do we breathe?
• How does blood flow?
• How do RBCs
transport O2?
• Why do we breathe?
• Why does blood flow?
• Why do RBC transport
O2?

5. Level of structural organization
Cells may differ
markedly from one
to another,but they
all share certain
basic
characteristics

6. The cell
The basic unit of the body
•Each human being begins as a single cell (i.e. fertilized egg).
•The number of cells increase by cellular division.
•The process of transforming an unspecialized cell into a specialized cell is known as differentiation.
Cells may differ markedly from one another, but they all
share certain basic characteristics.
Cell structure
Cell organelles
•N
u
c
l
e
u
s
.
•
R
i
b
o
s
o
m
e
s
.
•
E
n
d
o
p
l
a
s
m
i
creticulum:R
o
u
g
h&
S
m
o
o
t
h
•Golgia
p
p
a
r
a
t
u
s
.
•Mitochondria.
•
L
y
s
o
s
o
m
e
s
.
•
P
e
r
o
x
i
s
o
m
e
s
.
•C
y
t
o
s
k
e
le
t
o
n
.
Cell membrane
Willb
ed
i
s
c
u
s
s
e
dlater
● functionofe
a
c
ho
r
g
a
n
e
l
l
e
s

7. Tissues
A collection of a single type of specialized cells = tissue.
The combination of two or more types of tissues forms an organ.
Several organs come together and are organised into a system.

8. Types of tissues
Four types
Muscle tissues:
Is specialized to
generate mechanical
force
Nervous tissues:
Is specialized to initiate,
integrate, and conduct
electrical signals to other
cells
These signals may:
-Initiate new electrical signals
in other neurons
-Stimulate a gland to secrete
hormones
-Stimulate muscle contraction
Smooth muscles
Skeletal Muscles Cardiac muscles
The rest of the types is in the next slide

9. Types of tissues
Four types
Epithelial
tissues Connective tissues
It connects, anchors and
support the structures of the
body.
It consist of many and diverse
cell and tissue types, each with
its specific function.
•There are many shapes of epithelial cells according
to the function they need to perform.
•Thus, there are many types of epithelial tissue.
There are shared properties:
-It lines surfaces.
-Offers protection.
-May be involved in secretion and absorption
of ions & organic molecules.

10. Branches
There are a great number of disciplines that use the word
physiology in their title. Below are some examples:
•Cell physiology: studying the way cells work and interact; cell
physiology mostly concentrates on membrane transport and
neuron transmission.
•Systems physiology: this focuses on the computational and
mathematical modeling of complex biological systems. It tries to
describe the way individual cells or components of a system
converge to respond as a whole. They often investigate
metabolic networks and cell signaling.

11. Branches
There are a great number of disciplines that use the
word physiology in their title. Below are some
examples:
•Evolutionary physiology – studying the way
systems, or parts of systems, have adapted and
changed over multiple generations. Research topics
cover a lot of ground including the role of behavior in
evolution, sexual selection, and physiological changes
in relation to geographic variation.

12. Branches
There are a great number of disciplines that use the word
physiology in their title. Below are some examples:
•Defense physiology – changes that occur as a reaction to a
potential threat, such as preparation for the fight-or-flight
response.
•Exercise physiology – as the name suggests, this is the study
of the physiology of physical exercise. This includes research
into bioenergetics, biochemistry, cardiopulmonary function,
biomechanics, hematology, skeletal muscle physiology,
neuroendocrine function, and nervous system function.

13. Carry Home Message
1. Physiology is a science dealing with the way a
normal organism and their body parts function.
2. There are four types of body tissues.
3. There are four branches for studying human
physiology.

14. Thank You