Lecture 4

Question 1

what is an Endomembrane system

Answer 1

a membrane system interconnected by direct physical contact or transfer by vesicles

Question 2

what does the endomembrane system include

Answer 2

nuclear envelope, lysosomes, ER, vacuoles, golgi apparatus, plasma membrane and vesicles

Question 3

What are the two types of Endoplasmic Reticulum

Answer 3

Smooth and Rough

Question 4

What are the functions of sER

Answer 4

Metabolism of Carbohydrates
Lipid Synthesis/formation
Detox of Drugs/poison
Storage of calcium ions

Question 5

how does sER meet the demand of its processes in cells

Answer 5

it can increase/decrease to meet demand

Question 6

What is rER and what its functions

Answer 6

ER covered in ribosomes,

ribosomes for protein synthesis/production

Question 7

what happens to rER proteins

Answer 7

secreted and membrane-bound proteins enter lumen(inferior) of rER
Processed for release from cell or retention on cell membrane

Question 8

What is the Golgi Complex

Answer 8

series of membrane sacs and associated vesicles

Question 9

What are the functions of the Golgi Complex

Answer 9

Receives,modifies, sorts and ships proteins arriving from rER

Question 10

What are the cis and trans face of the Golgi complex

Answer 10

has polarity: cis and trans face
Vesicles from ER arrive at Cis face
Processed vesicles leave at trans face

Question 11

what is Glycosytation

Answer 11

the addition or modification of carbohydrate sugar to proteins, this is important for secreted or cell surface proteins

can also produces polysaccharide-can be secreted from cell

Question 12

how does the Golgi complex sort proteins

Answer 12

it adds markers to proteins to sort in correct vesicles leaving cell

Question 13

how does the Golgi complex direct vesicle trafficking

Answer 13

it tags vesicles with short proteins to direct to the lysosome and secretory pathways

Question 14

what is exocytosis

Answer 14

transport material/glycoproteins out of cell or to the cell surface

Question 15

What is constitutive exocytosis

Answer 15

relatively unregulated- releases ECM proteins

Question 16

what is regulated exocytosis

Answer 16

releases hormones and neurotransmitters

Question 17

What is endocytosis

Answer 17

process that takes in molecules/particles at plasma membrane

Question 18

what is Phagocytosis

Answer 18

when a cell is “eating” uptake of food particles

forms phagocytic vacuole (large vesicle), digested by lysosomes

Question 19

What is Pinocytosis

Answer 19

when a cell is “drinking”- extracellular fluid, containing solutes such as protein/sugars
coat proteins, helps with structure

Question 20

What is receptor-mediated endocytosis

Answer 20

specialized pinocytosis where receptors take up specific solutes that can take up low-concentration in bulk

Question 21

what are lysosomes

Answer 21

membrane-bound organelles made by rER and Golgi body, the interior is acidic/would kill cell but needed for enzyme activity

Question 22

what is the function of lysosomes

Answer 22

they degrade lipids, carbohydrates and nucleic acids- products into cell

Question 23

what is autophagy

Answer 23

digesting and recycling unwanted cellular material

Question 24

what are vacuoles

Answer 24

large vesicles dervied from rER and Golgi

food vacuoles-phagocytosis

Question 25

what are the functions of vacuoles

Answer 25

lysosomes functions
store organic compound (proteins,pigments)
absorb water for plant growth with increased cytoplasm