There are two major types of cells - prokaryotic and eukaryotic. Prokaryotic cells are simpler cells found in bacteria and archaea that do not have internal organelles or a nucleus. Eukaryotic cells are more complex, with internal membranes and organelles like the nucleus, mitochondria and chloroplasts. All living things are made of these basic cellular units that have evolved different structures and functions.

2. Cell Theory
 All living things are made up of cells.
 Cells are the smallest working units of all living things.
 All cells come from preexisting (‫قبلي‬ ‫وجود‬) cells through
cell division.

3. A cell is the smallest unit that is capable of
performing life functions.

4. Examples of Cells
Amoeba Proteus
Plant Stem
Red Blood Cell
Nerve Cell
Bacteria

5. •Prokaryotic
•Eukaryotic

6. Prokaryotic
 Do not have structures
surrounded by
membranes
 Few internal structures
 One-celled organisms,
Bacteria

7. Eukaryotic
 Contain organelles surrounded by membranes
 Most living organisms
Plant Animal

8. “Typical” Animal Cell

9.  A animal cell
Rough ER Smooth ER
Centrosome
CYTOSKELETON
Microfilaments
Microtubules
Microvilli
Peroxisome
Lysosome
Golgi apparatus
Ribosomes
In animal cells but not plant cells:
Lysosomes
Centrioles
Flagella (in some plant sperm)
Nucleolus
Chromatin
NUCLEUS
Flagelium
Intermediate filaments
ENDOPLASMIC RETICULUM (ER)
Mitochondrion
Nuclear envelope
Plasma membrane

10.  A plant cell
In plant cells but not animal cells:
Chloroplasts
Central vacuole and tonoplast
Cell wall
Plasmodesmata
CYTOSKELETON
Ribosomes (small brwon dots)
Central vacuole
Microfilaments
Intermediate
filaments
Microtubules
Rough
endoplasmic
reticulum Smooth
endoplasmic
reticulum
Chromatin
NUCLEUS
Nuclear envelope
Nucleolus
Chloroplast
Plasmodesmata
Wall of adjacent cell
Cell wall
Golgi apparatus
Peroxisome
Tonoplast
Centrosome
Plasma membrane
Mitochondrion

11. Organelles

13. Cell Membrane
 Outer membrane of cell
that controls movement
in and out of the cell
 Double layer

16. Nucleus
 Directs cell activities
 Separated from cytoplasm by nuclear membrane
 Contains genetic material - DNA

17. Nuclear Membrane
 Surrounds nucleus
 Made of two layers
 Openings allow
material to enter and
leave nucleus

18.  The nuclear envelope
 Encloses the nucleus, separating its contents from the
cytoplasm Nucleus
Nucleus
Nucleolus
Chromatin
Nuclear envelope:
Inner membrane
Outer membrane
Nuclear pore
Rough ER
Pore
complex
Surface of nuclear
envelope.
Pore complexes (TEM). Nuclear lamina (TEM).
Close-up of
nuclear
envelope
Ribosome
1 µm
1 µm
0.25 µm

19. Chromosomes
 In nucleus
 Made of DNA
 Contain instructions
for traits &
characteristics

20. Nucleolus
 Inside nucleus
 Contains RNA to build
proteins

21. Cytoplasm
 Gel-like mixture
 Surrounded by cell membrane
 Contains hereditary material

22. Endoplasmic Reticulum
 Moves materials around in
cell
 Smooth type: lacks
ribosomes
 Rough type (pictured):
ribosomes embedded (‫يجعله‬
‫جزءا‬) in surface

23.  The ER membrane
 Is continuous with the nuclear envelope
Smooth ER
Rough ER
ER lumen
Cisternae
Ribosomes
Transport vesicle
Smooth ER
Transitional ER
Rough ER 200 µm
Nuclear
envelope

24. Ribosomes
 Each cell contains
thousands
 Make proteins
 Found on ribosomes &
floating throughout
the cell

25. Mitochondria
 Produces energy through
chemical reactions –
breaking down fats &
carbohydrates
 Controls level of water and
other materials in cell
 Recycles and
decomposes (‫يحلل‬) proteins,
fats, and carbohydrates

26.  Mitochondria are enclosed by two membranes
 A smooth outer membrane
 An inner membrane folded into cristae
Mitochondrion
Intermembrane space
Outer
membrane
Free
ribosomes
in the
mitochondrial
matrix
Mitochondrial
DNA
Inner
membrane
Cristae
Matrix
100 µm

27. Golgi Bodies
 Protein 'packaging
plant'
 Move materials within
the cell
 Move materials out of
the cell

28. Golgi
apparatus
TEM of Golgi apparatus
cis face
)“receiving” side of
Golgi apparatus)
Vesicles move
from ER to GolgiVesicles also
transport certain
proteins back to ER
Vesicles coalesce to
form new cis Golgi cisternae
Cisternal
maturation:
Golgi cisternae
move in a cis-
to-trans
direction
Vesicles form and
leave Golgi, carrying
specific proteins to
other locations or to
the plasma mem-
brane for secretion
Vesicles transport specific
proteins backward to newer
Golgi cisternae
Cisternae
trans face
)“shipping” side of
Golgi apparatus)
0.1 0 µm1
6
5
2
3
4
 Functions of the Golgi apparatus

29. Lysosome
 Digestive 'plant' for
proteins, fats, and
carbohydrates
 Transports undigested
material to cell
membrane for removal
 Cell breaks down if
lysosome explodes

30.  Lysosomes carry out intracellular digestion by
 Phagocytosis (‫بلعم‬( )‫قووتدان‬)
(a) Phagocytosis: lysosome digesting food
1 µm
Lysosome contains
active hydrolytic
enzymes
Food vacuole
fuses with
lysosome
Hydrolytic
enzymes digest
food particles
Digestion
Food vacuole
Plasma membrane
Lysosome
Digestive
enzymes
Lysosome
Nucleus

31. Chloroplast
 Usually found in plant
cells
 Contains green
chlorophyll
 Where photosynthesis
takes place

32.  The cytoskeleton
 Is a network of fibers extending throughout the
cytoplasm Microtubule
0.25 µm Microfilaments

33.  Contains a pair of centrioles
Centrosome
Microtubule
Centrioles
0.25 µm
Longitudinal section
of one centriole
Microtubules Cross section
of the other centriole

35. There are two major types of cells
 Prokaryotic
 Found in Domains Bacteria and Archaea
 Kingdoms Eubacteria and Archaebacteria
 Eukaryotic
 Found in Domain Eukarya
 Kingdoms
 Plantae
 Animalia

36. Major Characteristics
 Prokaryotes
 Small
 Simple cells
 Have cell membrane, cytoplasm, ribosomes, DNA in
form of “nucleoid”
 Sometimes have cell wall, capsule, other projections
from wall (bacterial cilia, pili)
 DO NOT HAVE internal organelles or nucleus

37. Major Characteristics
 Eukaryotes
 Larger
 Complex cells
 Have cell membrane, cytoplasm, ribosomes, DNA in
form of “chromosomes”
 Sometimes have cell wall (plants and fungi) and
structures for movement (cilia and flagella)
 HAVE internal organelles and nucleus