Cystology

Question 1

What is the plasma membrane made of ?

Answer 1

phospholipids + proteins + cholesterol

Question 2

What is the function of cholesterol?

Answer 2

maintains fluidity + increases stability

Question 3

What is the function of glycoproteins?

Answer 3

provide shape, cell adhesion, signaling + transport

Question 4

What is the function of glycolipids?

Answer 4

stabilize the membrane structure

Question 5

What is the function of the rough ER?

Answer 5

protein translation + polypeptide formation

Question 6

What is the function of the smooth ER?

Answer 6

steroid hormone production + detox

Question 7

What is the function of the golgi apparatus?

Answer 7

protein modification + sorting (post office of cell)

Question 8

What is the function of lysosomes?

Answer 8

enzymatic break-down of cellular material

Question 9

What is the function of endosomes?

Answer 9

transport extracellular material

Question 10

What is the function of peroxisomes?

Answer 10

degrade fatty acids + toxins

Question 11

What is the name of the inner membrane fold in mitochondria? What is the function?

Answer 11

cristae; increases surface area for increased formation of ATP

Question 12

What is mitochondria stained with?

Answer 12

rhodamine 123 (immunocytochemical stain)

Question 13

What is the difference between smooth and rough ER?

Answer 13

rough: has ribosomes needed for protein translation -> results in polypeptide
smooth: NO ribosomes -> found in gonads + liver

Question 14

What is the golgi apparatus composed of?

Answer 14

stack of cisternae

Question 15

What is a lysosomal storage disease?

Answer 15

Tay-sachs

Question 16

What are the type of lysosomes?

Answer 16

phagocytosis -> phagolysosome
endocytosis -> endolysosome
autophagy -> autophagolysosome

Question 17

What does the residual body contain?

Answer 17

leftover material that COULD NOT be broken down

Question 18

Endosomes contain material from what?

Answer 18

phagocytosis, pinocytosis, and receptor-mediated endocytosis

Question 19

What membrane bound organelle contains oxidases?

Answer 19

peroxisomes

Question 20

What is energy released from oxidation converted into?

Answer 20

heat

Question 21

Where is the site of ribosome production?

Answer 21

nucleolus

Question 22

What are the non-membrane bound organelles?

Answer 22

1. microtubules, microfilaments, intermediate filaments -> part of cytoskeleton
2. centrioles -> cell division + microtubule organization center
3. ribosomes -> protein translation + synthesis

Question 23

What type of subunits make up microtubules?

Answer 23

alpha and beta -> form dimers -> form protofilaments

Question 24

Are alpha subunits on the plus or minus end?

Answer 24

minus end

Question 25

Are beta subunits on the plus or minus end?

Answer 25

plus end (growth of microtubule is the fastest on this end)

Question 26

Where does the microtubule assembly start from?

Answer 26

microtubule organization center = 1 centrosome

Question 27

What are microfilaments made of?

Answer 27

globular g-actin formed into filamentous f-actin

Question 28

Which end of the microfilament is the fast growing end?

Answer 28

plus end

Question 29

Which end of the microfilament is the slow growing end?

Answer 29

minus end

Question 30

When does polymerization into filaments occur?

Answer 30

when g actin > critical conc.

Question 31

What are the cytokeratins found in the epithelium?

Answer 31

type 1: acidic type 2: basic

Question 32

What is the function of centrosomes?

Answer 32

nucleation site for the formation of microtubules -> MTOC

Question 33

What is the function of molecular motors?

Answer 33

move organelles + other structures within a cell

Question 34

What are the major types of molecular motors?

Answer 34

kinesin, dynein, and myosin

Question 35

What are the functions of kinesin?

Answer 35

1. binds microtubules 2. moves anterograde = AWAY from nucleus -> towards plus end (beta subunit) 3. motor protein

Question 36

What are the functions of dynein?

Answer 36

1. binds microtubules 2. moves retrograde = TOWARDS nucleus -> towards minus end (alpha subunit) 3. role in ciliary + flagellar movement

Question 37

What are the functions of myosin?

Answer 37

1. binds microfilaments 2. moves anterograde = AWAY from nucleus -> towards plus end

Question 38

How are secondary lysosomes made?

Answer 38

* formed by fusion of primary lysosomes and phagosomes * formed by sites of active digestion of phagocytosed materials