Midterm 2

Question 1

When mitochondria become old they are enclosed by the membrane structure called _____ which will be eventually fused with lysosome

Answer 1

Autophagosome

Question 2

What is false about mitochondria?

Answer 2

Their membrane lipid is transferred from ER by vesicular traffic

Question 3

What is right about protein transport to mitochondria?

Answer 3

It needs Hsp70

Question 4

What is the right pathway of the transport of endocytic vesicles?

Answer 4

Early endosome - late endosome - lysosome

Question 5

Thickness of a microtubule is about _____

Answer 5

25 nm

Question 6

Thickness of the intermediate filament is about _____

Answer 6

10 nm

Question 7

Thickness of the actin is about ____

Answer 7

7-8 nm

Question 8

What is the most appropriate explanation about the function of fimbrin?

Answer 8

It bundles actin filaments into filopodia

Question 9

What is the most appropriate explanation about the function of troponin-C?

Answer 9

It binds Ca2+ to regulate muscle contraction

Question 10

What is the most appropriate explanation about the function of dystrophin?

Answer 10

It connects F-actin with transmembrane proteins that binds to the extracellular matrix in skeletal muscle

Question 11

ATP synthase is a large protein complex, which localizes on ____ of mitochondria

Answer 11

Inner membrane

Question 12

F1 region of the ATP synthase is facing to ____

Answer 12

Matrix

Question 13

______ subunit has two half-channels, each of which opens to opposite sides of the membrane

Answer 13

a

Question 14

Under normal conditions, _____ in intermembrane space come through the half channel from the _____ and transferred to _____ subunit. This results in sliding of the “c-ring” by one subunit

Answer 14

H+
Top
c

Question 15

Gradient of _____ is converted to the rotation of the c ring

Answer 15

H+

Question 16

Catalytic site of ATP synthesis belongs to _____ complex

Answer 16

alpha-beta

Question 17

While c ring rotates, _____ subunit(s) rotate with c ring

Answer 17

y

Question 18

As c ring rotates, _____ changes conformation to produce ATP from ADP and phosphate

Answer 18

alpha-beta

Question 19

The electron transport system pumps _____ of _____ ions,during transporting high energy electrons from one NADH (in matrix) to O2

Answer 19

10

H+

Question 20

A c-ring is made of _____ molecules of _____

Answer 20

12

c

Question 21

One revolution of c-ring produces _____ molecules of ATP

Answer 21

3

Question 22

In total, energy in one NADH will create _____ molecules of ATP

Answer 22

2.5

Question 23

When neutrophil moves toward attractant, cell protrusion is formed by local activation of _____-family proteins at the plasma membrane near the attractant

Answer 23

Rho

Question 24

Activation of Rho-family proteins is caused by binding of _____ to _____

Answer 24

GTP

Rho

Question 25

Upon activation, _____ interacts with _____, which starts do novo formation of F-actin at the plasma membrane

Answer 25

Rho

Formin

Question 26

_____ also indirectly stimulates _____, which creates new branch of F-actin

Answer 26

Rho

ARP

Question 27

The leading edge of the protrusion has ______-end of F-actin

Answer 27

Barbed

Question 28

In the cytosol F-actin is disassembled by ______, that creates G-actin form the filament

Answer 28

Cofilin

Question 29

ADP in the dissociated G-actin will be replaced by ATP by ____

Answer 29

Profilin

Question 30

When the membrane protrusion touches the extracellular matrix (or other surface) F-actin can be anchored to the extracellular material by the transmembrane protein _____

Answer 30

Integrin

Question 31

Kinesin-I has two heads and can walk on _____ by hydrolyzing ATP

Answer 31

Microtubule

Question 32

During the walking, kinesin changes conformation and “throw” one head over the other. This power stroke is coupled with _____

Answer 32

ATP binding