The study of cells

1
Cytology
The study of cells
2
Cell Theory
All living things are composed of cells
Cells are basic units of life
New cells come from pre-existing cells
3
Theres always exceptions to the rule
BUT.
How did the very first cell get here????
Viruses lack typical cell structure, use host
cells to reproduce
Mitochondria and chloroplasts have their own
genetic material/can reproduce independent of
cell
4
Prokaryotic Cells
Small
Simple
No Nucleus
No membrane bound organelles
Then what do they have?
Cell membrane
Cytoplasm
DNA
Circular, not in nucleus
Ribosomes
Bacteria
5
Prokaryotic Structure
cytoplasm with ribosomes
DNA
cell membrane
6
Eukaryotic Cells
More complex
Larger
Plant cells
DNA in nucleus in long strands
Contain membrane bound organelles
Specialized compartment with a specific function
Organelle
Animal cells
Fungi (Yeast)
7
(No Transcript)
8
Pro---No
Eu---Do
9
Organelles
10
Oh where, oh where do we find cell organelles?
Cytoplasm (protoplasm)
The fluid inside a cell, but outside the nucleus
Holds organelles in place
Site of cellular chemical reactions
Cyclosis
Streaming movement of cytoplasm
11
Cytoplasm
Cytoplasm
12
Nucleus
Controls cell processes
Contains hereditary information (DNA)
Nucleolus
Ribosome formation
13
Nucleus
Nucleolus
Nucleolus
Nucleus
14
Mitochondria
Release energy from food to make useable energy
(ATP)
Outer and inner membranes
Inner membrane folded
(Increased surface area)
Found in
Animal cells
Plant cells
Contain their own DNA!
15
Mitochondria
Mitochondria
16
Chloroplasts
Site of photosynthesis
Convert light energy to chemical bond energy
Only in plant cells
Contain their own DNA!
17
Chloroplasts
Animal cells dont have chloroplasts!!!
18
Ribosomes
Site of protein synthesis
Can be free in cytoplasm or attached to
endoplasmic reticulum
19
Ribosomes
Ribosomes
20
Endoplasmic reticulum
ER
A system of membranous sacs
Assembles components of cell membrane
Protein modification
21
Rough endoplasmic reticulum
Protein synthesis
Rough
Ribosomes
RER
Smooth endoplasmic reticulum
Contains enzymes needed for cell
Ex. enzymes for lipid synthesis
Smooth
No ribosomes
SER
22
(No Transcript)
23
Rough ER
Smooth ER
Smooth ER
Rough ER
24
Golgi Who? apparatus, complex, bodies
Marks proteins for use in cell or export (adds
address w/proteins)
Produces digestive enzymes
25
Golgi body
Golgi body
26
(No Transcript)
27
assorted vesicles
Golgi body
smooth ER
rough ER
DNA instructions for building protein chains
leave the nucleus and enter the cytoplasm.
Chains are assembled on ribosomes in cytoplasm.
28
Lysosome
Packaged by Golgi body
Membranous sac filled with digestive enzymes
Suicide Sacs
29
Lysosomes
30
Lysosome
Lysosome
31
Vacuole
Cell storage
Water Food Wastes
Plants
One large central vacuole
Animals
Few small vacuoles
Vacuoles are crucial in single-celled organisms
to maintain homeostasis
32
Vacuole
33
Cell Wall
Provides support
Provides shape
Made up mostly of cellulose
Animal cells dont have!
34
Cell wall
Animal cells dont have cell walls!!!
35
Centriole
Used in cell division
Animal cells only
36
Plant cells dont have centrioles!!!
Centriole
37
Cilia
Locomotion
Moving substances across surface of cell
Flagella
Locomotion
38
Cilia
39
Plasma membrane/cell membrane
Plant AND animal cells
Controls what goes in and out of cell
Protection
Support
40
Cell membrane
Cell membrane
41
Lipid Bilayer
lipid bilayer

• Main component of cell membranes

fluid
fluid
42
Cell (Plasma) Membrane Structure
2 layers of phospholipids (lipids
with phosphate groups attached) Proteins -
embedded in lipid layers- for transport
or receptors Carbohydrates - attached to
surface proteins or lipids markers
Lipids Proteins can move along membrane
Fluid
FLUID MOSAIC MODEL of Cell Membrane
43
(No Transcript)
44
Receptors recognize substances (hormones
etc.) and allow them to enter cell
45
(No Transcript)
46
How are plant and animal cells different?
Animal Cells Plant Cells
Cell Walls
Chloroplasts
Centrioles
Golgi Bodies
Vacuoles
NO
YES
NO
YES
NO
YES
1 or 2
100
Few Large
Many Small
47
Cell wall
Chloroplasts
Cell membrane
Vacuole
Mitochondria
Lysosome
Ribosomes
Golgi body
Nucleus
Rough endoplasmic reticulum
Nucleolus
Smooth endoplasmic reticulum
Cytoplasm
48
Cilia
Golgi body
Cell membrane
Centrioles
Smooth endoplasmic reticulum
Lysosomes
Free ribosomes
Mitochondria
Nucleolus
Rough endoplasmic reticulum
Nucleus
Cytoplasm
49
Staining Techniques
Applying stain makes cell structures more visible
Can be useful in identifying organisms
Example
Methylene blue
50
(No Transcript)
51
Organelle
Organization of Life
Cell
Tissue
Organ
Organ System
Organism