Chapter 4 : Cells
A. Cell Discovery
1. Robert Hooke – 1664 – saw
1st cell and named it a cell.
2. Schleiden, Schwann, and
Virchow - made up cell theory.
Cell Theory – says all living things are made
up of cells and only cells can make cells
B. Types of Cells
1. Prokaryote – cell that lacks membranebound organelles. No nucleus. Primative – ex.
Bacteria
2. Eukaryote – cell that has organelles
protected by membranes. More complex.
*** Evidence to support the idea that prokaryote
cells developed 1st and eukaryote cells resulted
when prokaryotic cells ingested each other.
C. Types of Eukaryotic Cells
1. Plant – has cell wall, large vacuole,
plastids (ex. Chloroplast), no centrioles
2. Animal – no cell wall, small vacuole,
centrioles, no plastids
D. Parts of Cell
--- organelle – “little organ”
1. Plasma or cell membrane – outer
membrane. Phospholipid (P+O+fat)
2. Cell wall – outer membrane of plants.
Made up of cellulose (we can’t digest)
3. Nucleus – control center of cell.
a. nuclear membrane – outside edge of
nucleus.
b. nucleolus – makes proteins
c. chromosomes – contains genetic
material (DNA)
d. nucleoplasm – fluid inside nucleus.
Used to protect organelles within nucleus.
4. Cytoplasm – clear fluid inside cell. Acts as
shock-absorber to protect contents of cell.
5. Endoplasmic reticulum (ER) – channels
used for transporting things within cell.
a. smooth ER – contains no ribosomes
b. rough ER – contains ribosomes. Used
for transporting molecules needed in
protein making.
6. Ribosomes – makes proteins
7. Golgi body or apparatus – packages
proteins and lipids.
8. Vacuole – storage area for food, water
and waste. Larger in plant cells.
9. Lysosome – “suicide sac” – contains enzymes
used to digest foreign materials and sometimes
the cell itself.
10. Mitochondria – “powerhouse of cell” – makes
energy by cellular respiration. Has many folds
called cristae that increases the surface area.
11. Chloroplasts – plastids that hold chlorophyll
(green pigment used for making food in plants)
12. Microtubules (bigger) & microfilaments
(smaller) – used for structural support –
called cytoskeleton.
13. Centrioles – only in animal cells. Used
during cell reproduction.
14. Cilia ( hair –like projections) & flagella
(long tail-like whip) – structures some cells
have for cell movement.
15. Perioxisomes- breakdown H2O2 into
water and oxygen