1. Cell Diversity

2. Cell Diversity
Cells of different organisms and even cells within the same organism are VERY diverse in terms of shape, size, and internal organization.
There are at least 200 different types of cells, ranging from flat cells to branching cells to round cells to rectangular cells!

3. Recurring Theme
One major theme in biology that occurs again and again is that form follows function!
In other words, a cells function influences its physical features.

4. Cell Shape
The diversity in cell shapes reflects the different functions of the cells
Compare the cells below. How does the nerve cell’s shape help it? The skin cell’s?

5. Cell Size Cells differ in their size as well as their shape
Some nerve cells that extend from a giraffe’s spinal cord to the foot can be 2 m long!
Most cells are about 1/500th the size of the period at the end of a sentence.

6. Cell Size
The size of a cell is limited by the relationship of the cell’s outer surface are to its volume aka surface area-to-volume ratio

7. Cell Volume
As a cell grows, the volume increases much faster than the surface area
Important because the materials needed by a cell and the wastes produced must pass in and out of the cell through its surface
If a cell were to become very large, the volume would increase more than the surface area, so materials wouldn’t be able to enter or leave quickly enough

8. Cell Volume

9. Basic Parts of A Cell
Plasma Membrane
Cytoplasm
Control Center

10. Plasma Membrane The cell’s outer boundary
Covers cell’s surface and acts as a boundary
Cannot be seen through a light microscope

11. Cytoplasm
The region of the cell that is within the plasma membrane and includes the fluid, the cytoskeleton, and all of the organelles
The cytosol is the part of the cytoplasm that includes molecules and small particles, but not membrane bound organelle

12. Control Center
Cells carry coded information in the form of DNA for regulating functions and reproducing themselves.
Some DNA floats freely in cells, other cells have a nucleus housing the DNA
Nucleus is a membrane-bound structure

13. Two Basic Cell Types Prokaryotes Eukaryotes
Lack membrane bound organelles
Have a nucleoid region where DNA is located
Bacteria and Archaea
Eukaryotes
Organisms made up of one or more cells and have membrane bound organelles
Much larger than prokaryotic cells

14. Prokaryotic Cell

15. Eukaryotic Cell

16. Cellular Organization
In multicellular organisms, cells organize into tissues, which organize into organs, then organ systems
Colonial organisms (colonies) are a groups of identical cells that live together in a connected group. These aren’t multicellular because their activities aren’t coordinated

17. Animal Cell
Cytoplasm
Nucleolus
Nucleus
Cell Membrane

18. Eukaryotic Cell Organelles and Function
Nucleus
Nickname: “The Control Center”
Function: holds the DNA
Parts:
Nucleolus: dark spot in the middle of the nucleus that helps make ribosomes

19. Animal Cell
Cytoplasm
Nucleolus
Ribosomes
Nucleus
Cell Membrane

20. Eukaryotic Cell Organelles and Function
Ribosomes
Function: makes proteins
Found in all cells, prokaryotic and eukaryotic

21. Eukaryotic Cell Organelles and Function
Endoplasmic Reticulum (ER)
Nickname: “Roads”
Function: The internal delivery system of the cell

22. Animal Cell Cytoplasm Nucleolus Ribosomes Nucleus Cell Membrane
Smooth Endoplasmic Reticulum
Rough Endoplasmic Reticulum

23. Endoplasmic Reticulum
2 Types:
Rough ER:
Rough appearance because it has ribosomes
Function: helps make proteins, that’s why it has ribosomes
Smooth ER:
NO ribosomes
Function: makes fats or lipids

24. Animal Cell Cytoplasm Ribosomes Nucleolus Nucleus Cell Membrane
Smooth Endoplasmic Reticulum
Rough Endoplasmic Reticulum
Golgi Complex

25. Eukaryotic Cell Organelles and Function
Golgi Complex
Nickname: The shippers
Function: packages, modifies, and transports materials to different location inside/outside of the cell
Appearance: stack of pancakes

26. Animal Cell Cytoplasm Nucleolus Ribosomes Nucleus Cell Membrane
Smooth Endoplasmic Reticulum
Rough Endoplasmic Reticulum
Golgi Bodies

27. Eukaryotic Cell Organelles and Function
Lysosomes: circular, but bigger than ribosomes)
Nickname: “Clean-up Crews”
Function: to break down food into particles the rest of the cell can use and to destroy old cells

28. Animal Cell Cytoplasm Nucleolus Ribosomes Nucleus Cell Membrane
Mitochondria
Rough Endoplasmic Reticulum
Smooth Endoplasmic Reticulum
Golgi Bodies

29. Eukaryotic Cell Organelles and Function
Mitochondria
Nickname: “The Powerhouse”
Function: Energy formation
Breaks down food to make ATP
ATP: is the major fuel for all cell activities that require energy

31. Animal Cell Cytoplasm Nucleolus Ribosomes Nucleus Cell Membrane
Mitochondria
Rough Endoplasmic Reticulum
Smooth Endoplasmic Reticulum
Golgi Bodies

32. Now let’s talk about structures only found in PLANT Cells!!

33. Plant Cell
Vacuole
Cell Membrane

34. Eukaryotic Cell Organelles and Function
Vacuoles
Function: stores water
This is what makes lettuce crisp
When there is no water, the plant wilts

35. Plant Cell
Vacuole
Chloroplasts
Cell Membrane

36. Eukaryotic Cell Organelles and Function
Chloroplasts
Function: traps energy from the sun to produce food for the plant cell
Green in color because of chlorophyll, which is a green pigment

37. Chloroplasts

38. Plant Cell
Vacuole
Chloroplasts
Cell Membrane
Cell Wall

39. Eukaryotic Cell Organelles and Function
Cell Wall
Function: provides support and protection to the cell membrane
Found outside the cell membrane in plant cells

40. Plant Cell Cytoplasm Vacuole Smooth ER Ribosomes Chloroplasts
Cell Membrane
Cell Wall
Nucleolus
Golgi Bodies
Nucleus
Mitochondria
Rough ER

41. Comparing Plant and Animal Cells
Moon
Animal
Plant