B: Endocytosis, Autophagy, Cytoskeleton (21)

Question 1

What does COP stand for

Answer 1

COat Protein complex = COP

Question 2

What is the purpose of the COT

Answer 2

Help with the traffic between the ER and golgi

Coat proteins that help to form transport vesicles, select cargo, and direct them to a target compartment

Question 3

How do coatamer proteins work

Answer 3

Works by recognizing transmembrane protein, binding with them and making vesicle that moves in that direction

COP released once vesicle made

Question 4

What is the AP complex

Answer 4

Adaptor protein complex

Question 5

What are adaptor proteins and calathrin

Answer 5

2 types of coatamers

Question 6

What is the role of Calathrin and AP

Answer 6

AP/Clathrin -coated vesicles move from TGN (trans-golgi network) to other vessicomes (lysosomes, endosomes, ect)

Question 7

Where does catherin move vesicles

Answer 7

Catherin moves golgi to late endosome

Question 8

What are the 2 key functions of lysosomes

Answer 8

1. Autophagy
2. Degradation of internalized material

Question 8

Where does the AP complex move vesicles

Answer 8

AP complex moves golgi to plasma membrane

Question 9

What is autophagy

Answer 9

Autophagy: normal disassembly of unnecessary of dysfunctional cellular components - organelle turn over

Question 10

Explain how lysomes help the degredation of internalized material

Answer 10

Recycling of plasma membrane components like receptors and extracellular materials

Destroy pathogens like bacteria and viruses - only in phagocytic cells

Question 11

Explain the structure of plant vacoules

Answer 11

Vacuoles are fluid-filled, membrane bound

They can take up about 90% of plant cells

Question 12

What are the function of plant vacoules

Answer 12

1. Intracellular digestion
2. Mechanical support
3. Storage

Question 13

Explain intracellular digestion in plant vacoules

Answer 13

• Comparable to lysosomes in animal cells
• acid hydrolisis

Question 14

Explain mechanical support in plant vacoules

Answer 14

Supports soft tissue
Stretches cell wall during growth

Question 15

Explain storage in plant vacoules

Answer 15

Chemical storage of toxic compounds and pigments

Question 16

What is the cytoskeleton

Answer 16

Dynamic network of interconnected filaments and tubes that extend through cytosol (and some organelles) of eukaryotes

Question 17

What are the 4 functions of the cytoskeleton

Answer 17

1. Structural support
2. Spacial organization within cell
3. Intracellular transport
4. Contractility and motility

Question 18

What are the 3 components of cytoskeletons

Answer 18

Microtubules - highway (25 nm)
Intermediate filaments - exits (10 nm)
Microfilament - roads (7-9 nm)

Question 18

What are microtubules made of (in the cytoskeleton)

Answer 18

Polymer of 2 different proteins (monomers): alpha and beta tubulin

Question 19

What are the 2 major types of microtubules (in the cytoskeleton)

Answer 19

1. Axonemal MT
2. Cytoplasmic MT

Question 20

What are the charges on microtubules, how does it affect function?

Answer 20

Negatively charged end connected to centrosome
Positive end can expand and contract rapidly

Question 20

What is the structure of microtubules

Answer 20

• Alpha/beta heterodimers form long protofilaments
• 13 protofilaments form longitudinal array creating hollow cylinder

Question 21

What is the role of the MTOC

Answer 21

Microtubule-organizing center (MTOC) is a central site of MT assembly

Question 22

What does MAPs stand for

Answer 22

Microtubule-associated proteins

• Several different proteins that bind MTs

Question 23

What are the 2 classes of MAPs

Answer 23

1. Non-motar MAPS
2. Motar MAPS

Question 24

What is the role of non-motar maps

Answer 24

Control MP organization in cholesterol

Question 25

What are the role of motar MAPS

Answer 25

Use ATP to generate force

Can move material along MT track

Can generate sliding forces between MTs