Discovery of Cells

1
Discovery of Cells

• Cells- smallest unit of matter that can carry on
  all the processes of life.

2
Discovery of Cells

• Leewenhoek was one of first inventors of
  microscope and therefore one of first to describe
  microscopic organisms and living cells.

3
Discovery of Cells

• Hooke named them cells influenced others to
  explore their existence.

4
The Cell Theory

1. All living things are made of 1 or more cells
2. Cells are basic units of structure and function
   in an organism.
3. Cells come from preexisting cells.

5
The Cell

• There are 2 types of cells
• Prokaryotic
• Eukaryotic

6
Prokaryotic Cells

1. No nuclear membrane
2. No membrane bound organelles (except ribosomes!)
3. Found only in Kingdoms Eubacteria and
   Archaebacteria
4. Extremely small

7
Eukaryotic

1. Definite membrane bound nucleus
2. Contains membrane bound organelles
3. Found in Kingdom Animal, Plant,
   Fungi, Protista
4. Slightly larger

8
Factors governing cell size

• Functions of the cells More activity, more
  organelles, larger cells
• Surface area Volume Ratio
• (small animal, high metabolism)

9
Cell Organelles

1. Nucleus- Control center of cell surrounded by a
   double-layered membrane. (Nucleolus Houses DNA)

10
Cell Organelles

• 2. Golgi Apparatus- Shipping Plant. Flat
  membranous sacs (like pancake stack). Function
  synthesis, storing, shipping materials.

11
Cell Organelles

• 3. Lysosomes- Garbage disposal collection.
  Sacs full of disgestive enzymes. Some store food.

12
Cell Organelles

• 4. Vacuoles- Also digestive sacs. Pump out
  excess material, digestion, store food. Mostly
  in plants protists.

13
Cell Organelles

• 5. Mitochondria- Power plant. Location where
  energy is produced (cell respiration). Double
  membrane (outer-smooth inner-folded called
  cristae). Has own DNA

14
Cell Organelles

• 6. Chloroplast- Site of photosynthesis. Double
  membrane (outer-smooth inner-stacks of coins
  call thylakoid membrane). Special plastid only
  in plant cells.

Sunlight H20 CO2 Glucose O2
15
Cell Organelles

1. Cytoskeleton- Cell skeleton. Support movement.
   Microtubules (hollow) microfilaments (solid).
   Cilia flagella are special microtubules on the
   outside of cells for movement.

16
Cell Organelles

• 8. Ribosome- Protein Synthesis. Works w/ RNA.
  Small round organelles in cytoplasm on
  endoplasmic reticulum.

17
Cell Organelles

• Endoplasmic Reticulum- Highway of cell.
• Rough ER- Has ribosomes. Protein synthesis and
  movement.
• Smooth ER- lipid production movement

18
Cell Organelles

• 10. Cell Wall- Made of cellulose. Only in plant
  and bacteria cells. Provides stability and
  framework.

19
Cell Organelles

• 11. Cytoplasm- liquid part of cell
• 12. Cell Membrane- Boundary of the cell.
  Semipermeable.

20
Cell Organelles

• 13. Centrioles- special microtubules that assist
  in mitosis (cell reproduction).
• Centriole