Chloroplasts, Apoptosis, Endomembrane (Transport)

Question 1

-Transport of material between compartments

Answer 1

-Organelle ↔ PM
- Organelle↔ Organelle

-Utilizes transport vesicles (~50-70nm)
-Small, spherical, membrane - enclosed organelles that bud off donor compartments and fuse with acceptors or recipient compartment

• Targeted movement (directed)
  -Uses cytoskeleton and motor proteins
  -Sorting signals recognized by receptors

Question 2

Key elements of vesicle trafficking compartments (Step 1)

Answer 2

1. Movement of vesicle - uses cytoskeleton and motor proteins (can be anterograde or retrograde)

Question 3

Key elements of vesicle trafficking compartments (Step 2)

Answer 3

2. Tethering vesicle to target compartment -via proteins from the Rab family of protein and other more specialized proteins

Question 4

Key elements of vesicle trafficking compartments (Step 3)

Answer 4

3. Docking vesicles to target compartments (uses proteins called snares)

Question 5

Key elements of vesicle trafficking compartments (Step 4)

Answer 5

4. Fusion of vesicle and membrane

Question 6

Transport of transmembrane proteins

Answer 6

Orientation of transmembrane proteins with respect to the cytoplasm and the interior of membrane - bound compartments is maintained during its travel through the endomembrane system

Question 7

Exocytosis

Answer 7

A vesicle from the inside of the moves into the cell surface, the vesicle membrane fuses with the cell membrane (restoring the membrane removed)

Question 8

Endocytosis

Answer 8

When the cell membrane folds inwards trapping and enclosing small amounts of matter from the extracellular fluid

Question 9

Pinocytosis

Answer 9

(A form of endocytosis)
- “cell drinking”
-The intake of a small droplet of extracellular fluid, together with any dissolved substance or very small particles that it may contain

Question 10

Phagocytosis

Answer 10

(A form of endocytosis)
- Is the intake of a large droplet of ECF, often including particular matter such as bacteria or bits of organic material

Question 11

Receptor-assisted endocytosis

Answer 11

-Involves the intake of specific molecules that attach to special proteins in the cell membrane that serve as receptors

-These membrane receptors passes a uniquely shaped projection or cavity that fits the shape of only one specific molecule