Topic vacuoles

1. Vacuoles
 Membrane bound spaces with a cell
 May be small-food storage
 May be quite large like the tonoblast in plant cells

2. Tonoplast and Central Vacuole
 Storage for many chemicals
 Ions, proteins, water
 Often plays role in tissue specific role
 Pigment of flowers, toxins for defense
 Can elongate to take up more or less space within cell

3. Fig. 6-15
Central vacuole
Cytosol
Central
vacuole
Nucleus
Cell wall
Chloroplast
5 µm

4. Mitochondria and Chloroplasts
 Both are power providers of cell
 Chloroplasts are like solar power plants
 Mitochondria are like coal-burning plants
 Both are membrane-bound organelles
 Both contain their own DNA which encodes
some proteins and ribosomes specific for their
activity
 Both move about within cell and divide to
form more organelles.

5. Endosymbiant Theory
 Chloroplasts and Mitochondria have evolved
directly from bacteria that were internalized
into anther prokaryotic cell
 Mitochondrial ancestor was effective at
respiration and utilizing complex chemicals
 Chloroplast ancestor was photosynthetic and
able to derive energy from sunlight
 Mutualistic relationship-where both partners
benefit from the interaction

6. Mitochondrial structure
 Mitochondria is responsible for respiration
 Reactions are membrane-associated
 Maximized membrane surface area
 Many proteins are bound to inner membrane
 Cristae are folds of inner membrane
 Matrix is the fluid surrounding cristae

7. Fig. 6-17
Free
ribosomes
in the
mitochondrial
matrix
Intermembrane space
Outer
membrane
Inner
membrane
Cristae
Matrix
0.1 µm

8. Chloroplasts
 Have double membrane with space in between
 Have additional membrane structures called thylakoids within-where
chlorophyll is stored
 Look like poker chips
 Stroma surrounds thylakoids
 Interaction between stroma and thylakoids is
important

9. Fig. 6-18
Ribosomes
Thylakoid
Stroma
Granum
Inner and outer
membranes
1 µm