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Flashcards in Motor physiology Deck (40):
1

Type II muscles: glycolytic or oxidative?

Glycolytic

2

Soleus and antigravity muscles of the back are examples of type __ muscle fibers.

Type I

3

What kind of smooth muscles have gap junctions?

Unitary or syncytial or visceral smooth muscles

4

There is no true AP propagation in this type of smooth muscle

Multi unit smooth muscle

5

Examples of unitary smooth muscles

Intestines
Bile ducts
Ureters
Uterus

6

Thick filaments are composed of

Myosin

7

Area between two z lines

Sarcomere

8

Stabilizes sarcolemma and prevents contraction-induced rupture

Dystrophin

9

The H zone contains: myosin only, actin only, both myosin and actin

Myosin only!

10

Which does not shorten during skeletal muscle contraction?

A band which represents entire length of myosin

11

Binds z lines to sarcolemma

Desmin

12

Depolarization of T tubules causes

Activation of dihydropyridine receptor in T tubules

13

DHPR causes activation of _______ receptor which releases ______ ions

Ryanodine
Calcium

14

Calcium binds to what troponin?

Troponin C

15

When ATP binds to cleft on myosin head, there is conformational change which causes _______ affinity of myosin for actin

Decreased affinity

16

ATP hydrolysis causes recocking of Myosin head. True or False?

True!

17

Distance achieved in a single power stroke

10 nm

18

Basis for Treppe effect

Calcium accumulation
Ph changes
Increased temperature

19

Pushing against the wall is isometric or isotonic contraction?

Isometric

20

Load is held constant in _______ contraction

Isotonic

21

Protective mechanism to prevent muscle injury or death

Muscle fatigue

22

Phase 2 of cardiac muscle contraction is the _______ and is due to _____ of _________

Plateau
Calcium influx

23

Phase 0 of cardiac AP is due to

Na influx

24

Why is there no tetany in cardiac muscles?

Long phase 2 ( long refractory period)

25

Phase 3 or final repolarization is due to

Decrease Ca influx
Increased K efflux

26

In the smooth muscle, calcium binds to ________ which is similar to troponin C of skeletal muscle

Calmodulin

27

________ phosphorylates myosin

Activated myosin light chain kinase

28

Alpha motor neuron is for _______ fibers

Extrafusal

29

Intrafusal fibers is associated with

Gamma motor neurons

30

Muscle spindle detect changes in muscle

Length and rate of change of muscle length

31

Golgi tendons are arranged in a ______ manner and detect changes in muscle _____

Parallel
Tension

32

Sense of awareness of the position of body in space

Proprioception

33

Proteins in smooth muscle that are equivalent to troponin I

Caldesmon
Calponin

34

_______ motor neurons are the final common pathway

Alpha motor neurons

35

Purkinje layer of the cerebellum is always __________

Inhibitory

36

Symptoms of cerebellar dysfunction

Ataxia dysmetria dysdiadochokinesia

37

Function of Renshaw cells

Inhibitory cells in the ventral horns of the spinal cord

38

Flexor withdrawal reflex is an example of a ______ synaptic reflex

Polysynaptic

39

Opposite of stretch reflex

Golgi tendon reflex

40

Functional unit of the muscle

Sarcomere