1. CELLS
Unit 4

2. Discovery of Cells Anton van Leeuwenhoek:
Made improvements to the simple microscope in 1648
Saw microscopic critters in pond water 1674

3. Discovery of Cells Robert Hooke
1st person to see cells & identify them – saw cell walls in cork 1665;
He gave ‘cells’ their name!

5. Prokaryotic Cells Eukaryotes Cells
2 Types of Cells
Prokaryotic Cells
and
Eukaryotes Cells

6. Prokaryotes Ex: All bacteria The cell DOES NOT have a “true” nucleus;
Tend to be smaller than Eukaryotes
Not as many organelles as Eukaryotes
Ex: All bacteria

7. Eukaryotes The cell HAS a “true” nucleus
Eukaryotes contain organelles which are special structures that perform important cellular functions
Ex: All plants, animals, fungi, & protists

8. Similarities and Differences in Prokaryotes and Eukaryotes
Both
Eukaryotes
Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton
Cell membrane
Contain DNA
Cytoplasm
Ribosomes

10. Cell Organelles 1
Tiny structures inside the cell that perform functions
The organelles are to the cell as the organs are to the whole body
Cells  Tissues  Organs  Organ Systems  Organism

11. NUCLEUS The control center of the cell
contains DNA, chromatin, & chromosomes
DNA contains coded instructions needed to make proteins
Chromosomes are thread-like structures that contain genetic material

13. CYTOPLASM Gel-like material in the cell
organelles are suspended in the cytoplasm

14. Ribosomes
Makes proteins with the help of RNA and Amino Acids

15. Endoplasmic Reticulum
Moves materials around the cell
Assembly of Lipids
Assists with Protein Synthesis
Rough ER: contains ribosomes
Smooth ER: no ribosomes

16. Mitochondria: makes ATP (energy); found in both plants & animals
“Power-house” of the cell
makes ATP (energy); found in both plants & animals
Converts food into compounds that the cell uses for growth, development, and movement

17. Chloroplasts: Found only in plants, bacteria, and some protists
Converts energy from sunlight into chemical energy by photosynthesis
Found only in plants, bacteria, and some protists

18. Golgi Apparatus
Sorts & Packages proteins from the ER

19. Vacuole Stores water, salts, protein, & carbs
Plant cells have a single large vacuole (stores water)
Animal cells have many small vacuoles

20. Lysosomes:
Contains enzymes to digest waste

21. Cytoskeleton helps the cell maintain its shape
Contains microfilaments & microtubules

22. Cell Wall
Provides support and protection for the cell; found in plant cells and bacteria

23. Cell Membrane
Regulates what enters and leaves the cell; found in both plant & animal cells
Composed of a Lipid bilayer (contains lipids and proteins)

24. Lipid Bilayer Carbohydrate chains Proteins Cell membrane Protein
Outside
of cell
Inside
(cytoplasm)
Cell
membrane
Proteins
Protein
channel
Lipid bilayer
Carbohydrate
chains

25. Animal Cell – rounder shape; no cell wall; no chloroplasts

27. How a school is like a cell

28. Just as the Administrative assistant controls what enters and leaves the school, so the plasma membrane regulates what leaves and enters the cell.

29. Just as the princible directs all operations that go on in the school, so the nucleus and DNA controls all cell activities and what proteins will be made.

30. Just as the school floor holds all the desks and every thing that’s on it, so the cytoplasm is were all the organelles and activities are found.

31. Just as the cafeteria kitchen is the place were the workers do their job making food, so the ER is the place were the ribosomes do their job of assemabling proteins

32. Just as the janitors clean up all the trash around the school and recycles the things that can still be used, so the so the lysosomes break down the cell waste so the different parts can be reused.

33. Just as the support beams, walls, ceilings, floors, bricks, and cement support the school building, so the cytoskeleton supports and maintains the shape of the cell.

34. Just like lunch provides the students with energy to do there work, so the mitochondria are the source of ATP that is used for energy in cell processes.

35. Just as composting breaks down garbage from the students in the school, so the peroxisomes break down hazardous material such as hydrogen peroxide.

36. Just as the storage closets in the classrooms store material, so the smooth ER (edoplasmic reticulum) stores steroids and ions.

37. Just as the teacher directs the students into the auditorium for an assembly, so the necleolous directs the assembly of proteins with in the cell necleus.

38. Just as the buses drive kids to and from school, so the centrosome is were microtubes carry out transportation.