22. 1,000 g
10 min
Supernatant
20,000 g
20 min
80,000 g
60 min
150,000 g
3 hr
Pellet rich in
nuclei and
cellular debris
Pellet rich in
mitochondria
(& chloroplasts in plants)
Pellet rich in
āmicrosomesā
(membrane debris)
Pellet rich in
ribosomes
22
23. 2 Main Types of Cells
Prokaryotic
(Domains Archaea
& Bacteria)
Eukaryotic
(Domain Eukarya)
23
24. 24
Basic Features
of All Cells
Plasma
membrane
Cytosol:
semifluid
DNA:
Chromosomes
carry genes
Ribosomes
32. Structure of the Plasma Membrane
Outside of cell
Inside of cell
Hydrophilic
region
Hydrophobic
region
Hydrophilic
region
Proteins
Carbohydrate
side-chain
32
37. Surface area increases while
total volume remains constant
5
1
1
6 150 750
125 1251
6 61.2
Total surface area
[Sum of the surface areas
(height ļ“ width) of all boxes
sides ļ“ number of boxes]
Total volume
[height ļ“ width ļ“ length ļ“
number of boxes]
Surface-to-volume
(S-to-V) ratio
[surface area Ć· volume]
37
87. ā An early ancestor of eukaryotic cells engulfed a
nonphotosynthetic prokaryotic cell, which formed
an endosymbiont relationship with its host
ā The host cell and endosymbiont merged into a
single organism, a eukaryotic cell with a
mitochondrion
ā At least one of these cells may have taken up a
photosynthetic prokaryote, becoming the
ancestor of cells that contain chloroplasts
The Endosymbiont Theory
87
93. Microtubules
Thick, hollow rods
of tubulin
Maintain cell shape
Transport organelles
& entire cell
Separate
chromosomes during
cell division ā form
spindle
93
98. 98
Cilia &
Flagella
Both made of MTās
sheathed by plasma
membrane
9 + 2 MT
arrangement
Anchored to cell by
basal body
Motor protein
(dynein) drives
bending movement
132. 132
Extracellular
Matrix (ECM)
of Animal Cells
Made of glycoproteins:
Collagen,
proteoglycans,
fibronectin
ECM proteins bind to
receptor proteins
called integrins in
plasma membrane
138. Tight junctions prevent
fluid from moving
across a layer of cells
Tight junction
Tight junction
TEM
0.5 ļm
TEM
1 ļm
TEM
0.1 ļm
Extracellular
matrixPlasma membranes
of adjacent cells
Space
between cells
Ions or small
molecules
Desmosome
Intermediate
filaments
Gap
junction
138