1. CHAPTER 4
CELLS

2. 4.1 History of Cell Biology
OBJECTIVES:
Name scientists who first observed living and non living cells.
Summarize research that led to cell theory.
State 3 principles of Cell Theory
Explain why cells are basic units of life

3. Discovery of Cells Hooke Leeuwenhook Discovered cells in cork
1st to observe dead cells
Leeuwenhook
First to observe living cells
Described first cells as animulcules

4. Cell Theory Cell Theory has 3 parts
All living organisms are composed of one or more cells.
Cells are the basic units of structure.
Cells come only from the reproduction of existing cells.

5. Cellular Basis of Life All living things Have cells Obtain energy
Perform chemical reactions
Change with time
Respond to the environment
reproduce

6. 4.2: Introduction to cells
Objectives:
Describe 3 basic parts
Compare prokaryotic and eukaryotic cells
Analyze relationship between cells, tissues, organs, organ systems, and organisms

7. Cell Diversity
Cell shape reflects the different functions of the cell.
Cells not only differ in the shape but also the size.

8. Two basic types of cells
A. Prokaryotic Cells
Do NOT have a nucleus
Bacteria
B. Eukaryotic Cells
Has a nucleus
Has organelles

9. Ribosomes
and DNA
Has Nucleus
No Nuclear Membrane

10. Cell Organelles
Animal Cell
Plant Cell

11. Cell Organelles Plasma Membrane Cytoplasm Nucleus
Covers the cell and acts as a barrier between the inside and outside
Cytoplasm
Fluid inside the cell
Nucleus
Control center of cell
Controls most functions of the cell

12. Cell Organelles Nucleolus Ribosomes Mitochondria
Site of DNA (genetic material)
Ribosomes
Made of protein
Direct construction of protein
Mitochondria
Powerhouse of the cell
Transfers energy

13. Cell Organelles G. Rough endoplasmic reticulum
A. System of flattened sacs
B. covered with ribosomes
C. produces phospholipids and proteins
D. transport system
H. Smooth endoplasmic reticulum
A. builds lipids (cholestrol)
B. Abundant in liver and kidneys
C. Detox body

14. Cell Organelles I. Golgi Apparatus
A. Packages materials throughout the cell
Lysosomes
Contain enzymes
Cytoskeleton
Microtubules
Provide structure
Microfilaments
Contribute to cell movement

15. Cell Organelles L. Cilia A. many hairlike structures used for movement
Flagella
Tail like organelle
Assists in movement
Tail on human sperm cells
Centrioles
Organize cytoskeleton for cell division

16. Cell Organelles Cell Wall Vacuole Chloroplasts Outside plasma membrane
Found only in PLANT cells
Provides structure
Vacuole
Storage sac
Chloroplasts
Used in photosynthesis (green)

17. Cell WALL

18. Cell MEMBRANE

19. Nucleus: control center for the cell

20. 4. Ribosomes: grain like bodies on the ER & in the cytoplasm

21. 5.Endoplasmic Reticulum: (called ER) carry proteins and materials within the cell

22. 6. Golgi Body: receives and packages proteins from ER and distributes around cell and body (mailroom)

23. 7. Cytoplasm: clear gelatinous fluid inside a cell

24. 8. Vacuoles: storage area of the cell Plant has one large vacuole Stores food, waste, & enzymes

25. 9. Mitochondria = powerhouse of the cell; where cell energy comes from.

26. 10. Chloroplasts: ONLY IN PLANTS captures sunlight and produces food for the cell

27. 11. Flagella = used for movement

28. 12. Cilia = used for movement; tiny hair-like structures; found on cells that need to move mucus

29. COMPARE and CONTRAST Plant and Animal Cells
Cell Wall
Chloroplasts
Large Vacuole
Cytoskeleton
Nucleus
Cell Membrane

30. Importance of Cell Surface Area
What is surface area?
The amount of surface for a cell
Why is surface area important?
When the volume of the cell increases, the surface area increases
S.A. limits cell growth because if the cell becomes to large it will not be able to take in enough food and get rid of enough waste