1. Ch 4: Cell Structures Essential Questions:
How is the structure of the cell related to function?
How do cell malfunctions result in pathologies?
Practice Quiz:

2. Studying Cells Normal PAP
*Review the different types of microscopes and how they are used to view cells.*
CYTOLOGY = study of cells.
CYTOTECHNOLOGIST = professional who studies cells and determines if cells are abnormal; PAP test
Abnormal PAP

3. Cell Theory All living things are composed of cells
Robert Hooke, “Micrographia”
Anton van Leeuwenhoek, “Animalcules”
Schleiden and Schwann
All living things are composed of cells
Cells come from other cells
The cell is the basic unit of life

4. Cell Size

5. Cell Size Surface area and volume are limiting factors for cell size.
As cells grow too large, the membrane can’t transport enough materials.

6. Prokaryote Cells
Does not contain a membrane bound nucleus; smaller than eukaryotic cells
Domain: Bacteria & Archaea
All cells have:
Cytosol, Plasma membrane, ribosomes, DNA

7. Eukaryotic Cells Main Features Membrane-bound nucleus with chromosomes
Various organelles that perform specific functions.
Liquid interior is the cytoplasm (cytosol)

8. Endosymbiosis Theory
Provides a possible explanation for the origin of eukaryotic cells, particularly the mitochondria and chloroplasts.

9. Plasma Membrane
Phospholipid bilayer with embedded proteins

10. The Nucleus Nuclear Envelope Nucleoplasm Nucleolus - makes ribosomes
Chromosome (chromatin, DNA) - information storage

11. Ribosomes Site of protein synthesis
Floats in cytoplasm and found attached to endoplasmic reticulum
mRNA provides the code to build a chain of amino acids

12. Mitochondria CELLULAR RESPIRATION “Powerhouse” of the cell
Provide energy in the form of ATP
Specifically, they are responsible for
CELLULAR RESPIRATION
Has mitochondrial DNA that is separate from the cell’s DNA. Endosymbiosis theory suggests that eukaryotes evolved from prokaryotes and that the mitochondria was once a free-living prokaryote.

13. What happens if your mitochondria don’t work?
Mitochondrial Disease Video
Why is mitochondrial disease so devastating to children?
Consider the mitochondria have their own DNA separate from the parental DNA. How could you cure this disease?
Check out this video:
1. Inner Membrane Outer Membrane 3. Cristae Matrix

14. Peroxisomes Lysosomes
Small organelles that carry out oxidation reactions
Enzymes within them safely break down hydrogen peroxide.
Lysosomes
Found in animal cells, known as the “garbage disposal” because they break down substances (digestion)

15. GM2 ganglioside enters the nerve cell as a source of food
GM2 ganglioside enters the nerve cell as a source of food. Lysosomes contain an enzyme, Hex-A that digests GM2. Children with Tay-Sachs lack Hex-A, so the GM2 builds up within the cell and eventually kills it.
Ellie’s Story | Cure Tay-Sach’s Foundation

16. Vesicles and Vacuoles Used for storage and transport.
Vesicles can fuse with the membrane and transport materials out of the cell.
Plants have a large CENTRAL VACUOLE

17. Centrosomes (Centrioles)
Move chromosomes during cell division, builders of cytoskeleton
*Animal cells only

18. Chloroplasts Plant cells only - site of photosynthesis
Like the mitochondria, also has its own DNA

19. Cell Wall Only found in plant cells
Rigid structure made of peptidoglycan and cellulose
This make plants difficult to digest

20. I am a reticulated python
I am a reticulated python. Ask me what I have to do with the endoplasmic reticulum.
The word “reticulum” means net.

21. Endomembrane System
A group of organelles that work to process, package and secrete proteins.
Ribosomes make the proteins
Endoplasmic reticulum transports proteins (smooth vs rough)
Golgi Apparatus packages & exports (like a post office)

24. The Cytoskeleton
Network of fibers that gives support and structure to the cell:
Microfilaments / Microtubules / Intermediate Filaments (maintain shape)
Actin / Movement
Cilia and Flagella function in movement

25. The Big Picture

26. a. ________________ b. ________________ c. _________________
d.  _________________
e.  _________________
f.  __________________
g.  __________________
Pg 81 g. f.