Muscle

Question 1

skeletal muscle

Answer 1

attached to bone

striated

voluntary

nuclei around periphery

Question 2

cardiac muscle

Answer 2

heart

striated

involuntary - controlled by CNS

nuclei in the center

Question 3

smooth muscle

Answer 3

lacks striation

lines hollow organs

involuntary - controlled by CNS

Question 4

sarcoplasm

Answer 4

cytoplasm of muscle cells

Question 5

what controls involuntary muscles?

Answer 5

CNS

Question 6

muscle fiber

Answer 6

each muscle cell is multinucleated

Question 7

syncytium

Answer 7

multinucleated muscle fiber

Question 8

endomysium

Answer 8

delicate layer of reticular fibers that surrounds muscle fibers (cells)

Question 9

perimysium

Answer 9

thicker CT than endomysium

surrounds fascicles (bundles of muscle fibers)

Question 10

fascicles

Answer 10

bundles of muscle fibers surrounded by perimysium

Question 11

epimysium

Answer 11

sheath of dense CT that surrounds collections of fascicles (the entire muscle)

Question 12

myofibril

Answer 12

structural subunits of muscle fibers

Question 13

sarcolemma

Answer 13

cell membrane

surrounds muscle fiber

Question 14

sarcoplasmic reticulum

Answer 14

smooth ER surrounding myofibrils

Question 15

thin filaments

Answer 15

actin

Question 16

thick filaments

Answer 16

myosin

Question 17

Z line

Answer 17

dense outer line

alpha actin

Question 18

M line

Answer 18

center of the A band

Question 19

H band

Answer 19

just thick filaments

Question 20

sarcomere

Answer 20

basic contractile unit of striated muscle

Question 21

titan

Answer 21

longest protein known

polypeptide chain stretches along the whole sarcomere

functions as molecular spring

Question 22

What does “decorating” represent?

Answer 22

the unipolarity of thin filaments

Question 23

what does ATP function as in skeletal muscle?

Answer 23

dissociate myosin from the thin filament

also to move the myosin head via energy from hydrolysis

Question 24

What does Ca control in skeletal muscle?

Answer 24

contraction/relaxation by binding to a site on troponin which alters tropomyosin’s position exposing the myosin binding site on actin

Question 25

E-C coupling

Answer 25

binding of acetylcholine from neuron depolarizes sarcolemma and T-tubules which triggers Ca release from SR

Question 26

muscle spindle

Answer 26

sits in perimysium around fascicles special nerve fibers for proprioception

Question 27

Type I slow oxidative

Answer 27

red and slow contracting marathoner

Question 28

Type IIa | fast oxidative

Answer 28

Fast sprinter

Question 29

Type IIb | fast glycolytic

Answer 29

very fast pale muscles weight lifter

Question 30

satellite cell

Answer 30

precursor to myofibers located between cell membrane and basement membrane stimulate for increased growth

Question 31

dystrophin

Answer 31

is thought to link laminin, which resides in the external lamina of the muscle cell, to actin filaments. Absence of this protein is associated with progressive muscular weakness, a genetic condition called Duchenne’s muscular dystrophy. Dystrophin is encoded on the X chromosome, which explains why only boys suffer from Duchenne’s muscular dystrophy. Recently, characterization of the dystrophin gene and its product has been clinically important

Question 32

Unique to cardiac muscle

Answer 32

cardiac nuclei in middle cardiac functional syncytium T-tubules are larger intercalated disks with adherins, desmosomes, and gap junctions

Question 33

functional syncytium

Answer 33

cardiac muscle can have 2 nuclei but intercalated disks prevent it from being really multinucleated like skeletal muscle

Question 34

syncytium

Answer 34

skeletal cell - multinucleated

Question 35

atrial granules

Answer 35

found in atria of heart release ANF and BNF by exocytosis

Question 36

Calmodulin

Answer 36

what Ca binds to in smooth muscle activates a myosin light chain kinase