Cells
Definition of a cell: A cell is the smallest structural and functional unit of life
I.
II.
Prokaryotic cells
A.
fundamentally bacteria
B.
< 2 micrometers
C.
No nuclei
Eukaryotic Cells
A.
> 2 micrometers
B.
2 regions
C.
1.
nucleus
2.
cytoplasm
Membrane-bound organelles
III. Cell Theory
A.
Leaves
Schleiden:
all plants are composed of cells
B.
Kitten
Schwann: all animals are composed of cells
C.
Virchow formalized
D.
4 Parts
1.
Added Later: Activities of cells depend on their sub-cellular structures
2.
All cells are produced by the division of preexisting cells (asexual reproduction)
3.
Cell is the basic unit of structure and organization
a.
4.
Added: all basic functions are carried out in the cell
All living things are composed of cells
IV. Cell Organelles in Cytoplasm (Both Plant and Animal Cells)
A.
Plasma membrane: separates inside of cell from the outside
B.
Cytoplasm: A semi-fluid material inside the plasma membrane
C.
Lysosome: Digests food vacuoles, invading bacteria, and old organelles
D.
Mitochondria: Cellular respiration; where food energy is converted into ATP
E.
Microtubule: Aid in movement of cells
F.
ER: Rough: Has ribosomes; conveyor belt for protein protection; Smooth: Has no
ribosomes; makes steroids and lipids
G. Vacuole: Store water, sugars, and salts
H. Golgi apparatus: Modifies, packages, and sorts proteins
I.
V.
Ribosome: RNA protein factory
Cell Organelles in Cytoplasm (Plant Only)
A.
Cell Wall: Protects cell, controls what enters and leaves
B.
Chloroplast: Where sunlight is captured and converted into chemical energy
VI. Cell Organelles in Nucleus
A.
Stores information used to make proteins for cell growth, function, and reproduction
B.
Nuclear envelope: Double membrane that contains nuclear pores
C.
Nuclear pore: pores in the nuclear envelope to get messages in and out of the nucleus
D.
Nucleolus: Produces ribosomes
E.
Chromatin: DNA and protein