Lecture 5: Endomembrane system and bulk transport processes

Question 1

Endomembrane system includes:

Answer 1

nuclear envelope
endoplasmic reticulum
Golgi apparatus
vesicles
lysomes
vacuoles
plasma membrane

Question 2

Endoplasmic reticulum (ER) is comprised of:

Answer 2

smooth endoplasmic reticulum (sER)

rough endoplasmic reticulum (rER)

Question 3

Functions of sER:

Answer 3

Metabolism of carbohydrates
lipid synthesis for membranes
detoxification of drugs and poisons
storage of calcium ions

Question 4

Functions of rER:

Answer 4

• involved in protein synthesis

- process proteins for release from the cell or retention on cell membrane

Question 5

Functions of Golgi complex:

Answer 5

receive
modify
sort
ship proteins

Question 6

Golgi complex:

where vesicles arrive

Answer 6

cis face

Question 7

Golgi complex:

where processed vesicles leave

Answer 7

trans face

Question 8

Golgi complex:

glycosylation

Answer 8

adds carbohydrates to proteins

important for cell surface proteins

Question 9

Golgi complex:

sorting proteins

Answer 9

adds molecular markers to direct proteins to correct vesicles

Question 10

Golgi complex:

Directing vesicle trafficking

Answer 10

add molecular “tags” to vesicles

Question 11

Molecular tags are…

Answer 11

often short proteins that act as docking sites when they reach their targets

Question 12

molecular tags direct:

Answer 12

vesicles to the lysosome, secretory pathways

Question 13

Types of Exocytosis:

Answer 13

constitutive exocytosis

regulated exocytosis

Question 14

Role of exocytosis

Answer 14

transport glycoproteins out of the cell or deliver it to cell surface

Question 15

Constitutive exocytosis

Answer 15

releases extracellular matrix proteins

Question 16

Regulated exocytosis

Answer 16

releases hormones and neurotransmitters

Question 17

Endocytosis

Answer 17

uptake of molecules into the cell

Question 18

Phagocytosis

Answer 18

uptake of particles, then formation of phagocytic vacuole which is digested by lysomes

Question 19

Where phagocytosis occurs in humans

Answer 19

macrophages

Question 20

Pinocytosis

Answer 20

uptake of extracellular fluid containing solutes (proteins and sugars)

Question 21

Pinocytosis up-take is

Answer 21

non selective

Question 22

Up-take vesicle formation is aided by a

Answer 22

coat protein

Question 23

Receptor-mediated endocytosis is…

Answer 23

a specialised form of pinocytosis for selective uptake of bulk substance quantities

Question 24

Lysosomes

Answer 24

membrane bound organelles containing hydrolytic enzymes

Question 25

Lysosomes function:

Answer 25

break down proteins, lipids, carbohydrates and nucleic acids and release products into the cell

Question 26

Autophagy is

Answer 26

process of breaking down and recycling material

Question 27

Large vesicles derive from

Answer 27

rER and Golgi complex

Question 28

Food vacuoles are involved in

Answer 28

phagocytosis

Question 29

Function of vacuoles in plants:

Answer 29

perform lysosome-like functions

large central vacuole absorbs water