Phsiology

Question 1

what opens Ca channels ?

Answer 1

acethylcholine relase

Question 2

steps of muscle contraction

Answer 2

muscle cell depolarization
depolarization travels with t-tubules
DHPR-RR -- Ca relase
Ca bindes TnC and tropomyosin expose myosin binding sites
crossbrige forms
Pi released, power stroke happens
Muscle conracts

Question 3

Type I muscle ?

Answer 3

Slow twitch
red fibers
more mitochondria and myoglobin

Question 4

Type II muscle ?

Answer 4

Fast Twich
white fibers
less mitochondria and myoglobin

Question 5

Contraction - ?
Relaxation - ?
(smooth muscle )

Answer 5

Ca

Nitric oxide

Question 6

Contraction of smooth muscle mechanism ?

Answer 6

L-type Ca channel – Ca entry – Calmodulin complex – Myosin light chain kinase – Myosin-actin e P bağlar

Question 7

Relaxation of smooth muscle mechanism ?

Answer 7

ACh or Bradykinin – L-arginin to NO – NO diffusion to smooth muscle cells – GTP to cGMP – Myosin light chain phosphatase – takes away P

Question 8

Muscle spindle ?

Answer 8

Senses length and speed
type Ia (Chain, bag) and type II (chain)

Question 9

Golgi tendon organ ?

Answer 9

Senses tension

type Ib

Question 10

gama motor neurons ?

alpha motor neurons ?

Answer 10

cause intrafusal fibers to contract

cause extrafusal fibers to contract

Question 11

Osteoclast

Answer 11

crushes bone
Rank - RankL – osteclast aktivitesi
OPG - RankL – üstteki mekanizmayı önler

Question 12

Which hormone has anabolic effects on osteoblast at low, intermittent levels, cause catabolic effects with high levels ?

Answer 12

PTH

Question 13

Which hormone can cause osteoporosis ?

Answer 13

Estrogen