Muscles

Question 1

* Contraction of muscle cells depends on

Answer 1

1. Interaction of actin and myosin
2. Regulation of cellular calcium levels.

Question 2

* Viceral striated muscle

Question 3

*Myoblasts are derived from multipotential myogenic stem cells from the mesoderm and fuse together to form ?

Answer 3

Myotubules

Question 4

Activates muscle specific differentiation

Answer 4

MyoD

Question 5

Exerts inhibitory effect on growth and differentiation

Answer 5

Myostatin

Question 6

True regeneration of skeltal muscle is due to

Answer 6

Satellite cells

Question 7

Endomesium of muscle contains

Answer 7

laminin

Question 8

Collagen fibers insert themselves at the ends of muscle forming the?

Answer 8

Myotendinous junction

Question 9

Major protein at the M-line

Answer 9

Creatine Kinase

Question 10

Protein that anchors molecules at the sarcolemma

Answer 10

Dystrophin

Question 11

IF extending from one myofibril to the other and anchored to sarcoleema , encircles the Z disk of each sarcomere

Answer 11

Desmin

Question 12

links adjacent IF to each other

Answer 12

Plectin

Question 13

Heat shock protein associated with desmin, protects this IF from stress induced damage

Answer 13

alpha beta crystallin

Question 14

Muscular dysptrophy cause by

Answer 14

mutation in dystrophin (myofibrills can be misfolded)

Question 15

T-tubule system encircles the - band of each sarcomere in every myofibril.

Answer 15

A-I band

Question 16

T tubule with 2 lateral portions of SR is known as a

Answer 16

triad

Question 17

Muscle spindles also known as

Answer 17

encapsulated proprioceptors

Question 18

Muscle spindles are collectively called

Answer 18

intrafusal fibers

Question 19

Muscle spindles are innervated by

Answer 19

sensory nerves

Question 20

Skeletal muscle energy is obtained from

Answer 20

FA and glucose

* also must have deposits of energy to cope with bursts of activity , thus energy is available from glycogen granules.

Question 21

Type 1

Answer 21

slow oxidative fibers (lots of myoglobin)

enerygy derived from oxidative phosphorylation of fatty acids

Question 22

Type IIa

Answer 22

Fast oxidative glycolytic fibers

contains myoglobin and stores of glycogen

Question 23

Type IIb

Answer 23

fast glycolytic fibers

much less myoglobin

rapidly metabolized glucose from glycogen stores to lactate

Question 24

Cardiac cells branch to form

Answer 24

complex junctions

Question 25

Holds cardian muscle cells at their ends for stability and is the anchoring site for actin filaments of terminal sarcomeres

Answer 25

Fascia Adherens (Zonula adherens)

Question 26

Fascia Adherens (Zonula adherens)

Answer 26

Cardiac muscle cell stability

Anchors actin of terminal sarcomeres

Question 27

Runs parallel to myofilaments

Answer 27

Gap junctions

Question 28

Cardiac muscle cells posses diads that consists of

Answer 28

one t-tubule and one SR

Question 29

Cardiac energy metabolism

Answer 29

aerobic

FA main fuel source

Small amount of glucose is present and can be used in time of stress

Question 30

ANF secreted by RA

Answer 30

responds to high blood pressure

effect is to lower blood pressrue

Question 31

Purkinje fibers are innervated by

Answer 31

parasympathetic and sympathetic

Question 32

Smooth muscle cells are enclosed by

Answer 32

basal lamina

reticular fibers

Question 33

smooth muscle cells

Answer 33

are fusimform

single central muclus

Question 34

Caveolae

Answer 34

act like t tuble of SM

SM no t tubules

Question 35

Two types of dense bodies of SM

Answer 35

1. Membrane associated
2. Cytoplasmic

analogous to Z-line

Question 36

alpha actinin

Answer 36

actin anchoring protein

Question 37

Myosin interacts with actin only when

Answer 37

myosin light chain is phosphorylated

Question 38

What activated MLCK

Answer 38

Calcium calmodulin complex

Question 39

SM is innervated by

Answer 39

sympathetic and parasympathetic

receives both adrenergic and cholinergic endings that act antagonistically

Question 40

SM cells regerate by

Answer 40

hyperplasia and hypertrophy

viable cells can undergo mitosis