Lecture 15 Learning Objectives

Question 1

The sorting of lipids, protiens and polysaccharides begin the the ER, are sorted in the Golig and end up where?

Answer 1

Plasma memrbane, secretion, endosomes, lysosomes

Question 2

Which way is cis entry oriented?

Answer 2

towards the ER/nucleus

Question 3

what moves proteins through the golgi?

Answer 3

transport vesicles

Question 4

what way is the trans golig netowkr oriented?

Answer 4

The trans golgi is pointed towards the exit into the cell membrane

Question 5

Modification of N-linked oligosaccharides function?

Answer 5

trimmed on mannose (man) except in high-mannose oligosacchraides

and

Addition of complex oligosaccharides and O-linked oligoccachirdes

Question 6

Lysosomal proteins modification function?

Answer 6

Sorting Mannose-6-p

Question 7

Which of the following statements about
the Golgi Apparatus is** FALSE:**
A. The Golgi apparatus is a polarized
organelle
B. The Golgi apparatus consists of many
tubular ducts connected to one
another in a widespread network.
C. The Golgi apparatus is a major
glycosylation center of the cell.
D. The Golgi apparatus is involved in both
exocytosis and endocytosis pathways.

Answer 7

Which of the following statements about

Question 8

How does the structure of the Golgi reflect its function?
A. It is continuous with the nuclear envelope
B. Its stacked cisternae facilitate sequential enzyme processing
C. Its single membrane allows it to function like the cytosol
D. It forms ribosomes needed for protein targeting

Answer 8

B. Its stacked cisternae facilitate sequential enzyme processing

Question 9

Which of the following best explains why different enzymes
are localized to different cisternae in the Golgi stack?
A. All Golgi enzymes are randomly distributed
B. Each cisterna specializes in distinct modifications
C. Enzymes are inserted only into the trans face
D. Enzymes are secreted with the proteins they modify

Answer 9

B. Each cisterna specializes in distinct modifications

Question 10

COPII sorts in which direction?

Answer 10

ER → Golgi (anterograde transport)

Question 11

COP I sorts in which direction?

Answer 11

Golgi → ER (retrograde/retrieval transport

Question 12

Secretory pathways (exocytosis) use

Answer 12

secretory vesicles

Question 13

Protein sorting in TGN

what is regulated secretion?

Answer 13

the controlled and rapid releasr that happen in response to a signal

Question 14

Protein sorting in TGN

what is constitivutive secretion?

Answer 14

continous discharge of vesicles at the plasma membrane

Question 15

Acid Hydrolases in Lysosomes

Answer 15

acid hydrolasea are hydrolytic enzymes that are active under acidic condiitons. ATPase in the membrane pumps H+ into the lysosome, this maintins its lumen at acidic PH. Releasing ADP + P

Question 16

What pathways deliver material to lysosomes?

Answer 16

Multiple including: endocytosis, macropinocytosis, phagocytosis, and asutphagy

Question 17

Which of these organelles function as
intracellular digestive systems and contain
enzymes?
A. Lysosomes
B. rough endoplasmic reticulum
C. Golgi apparatus
D. Nucleus
E. Secretory vesicles
20

Answer 17

A. Lysosomes

Question 18

What is the clarthin coat regarding lysosomes?

Answer 18

A protein cgae that forms on the surface of a cell membrane in order to hspae and transport vesicles during intraceullular transport

Question 19

What is Mannose 6-P?

Answer 19

A sorting signal

Question 20

What is phagocytosis?

Answer 20

“cell eating: of large particles like bacteria

Question 21

What is Pinocytosis?

Answer 21

“cell drinking” of fluids ann small solutes

Question 22

What is receptor mediated endocytosis?

Answer 22

A highly specified process for taking in specific macromolecules using receptors on the cell surface?

Question 23

Clarthin mediated Endocytosis

Answer 23

Receptor mediated enducytos and pinocytosis

Question 24

Which of the following accurately describes a function
of the late endosome?
A. Synthesizing lysosomal enzymes
B. Sorting materials for degradation or recycling
C. Generating ATP for the lysosome
D. Directly fusing with the ER to degrade misfolded
proteins

Answer 24

B. Sorting materials for degradation or recycling

Question 25

What is recycling endosome?

Answer 25

redistribution to other memrbanes and recycling of plasma membrane components

Question 26

What happens when recycling endosomes?

Answer 26

recycling to the original membrane, and transcytosis which is redistribution to other membranes

Question 27

After receptor-mediated endocytosis, what is the orientation of the receptor’s ligand-binding domain in the early endosome? A. Facing the cytosol, just like at the plasma membrane B. Facing the lumen of the endosome C. Embedded entirely in the membrane, inaccessible D. Removed from the membrane during vesicle budding 25

Answer 27

B. Facing the lumen of the endosome

Question 28

What is a regulated secretory pathway?

Answer 28

the controlled and rapid release that happens in response to a signal (hormone)

Question 29

What is constituvtive secretion?

Answer 29

the continous dischagre of vesicles at the plasma membrane

Question 30

Man6P groups are added in the trans Golgi to the precursors of hydrolases that composed

Answer 30

lysosomes

Question 31

what are synaptuc vesicles?

Answer 31

nerve cells formed from endosomes