Lecture 3 - Muscular Tissue

Question 1

what are the major divisions of muscle tissue, in descending order?

Answer 1

muscle -> fascicles -> muscle fibers -> myofibrils -> myofilaments

Question 2

def: surrounds a muscle and is continuous with fascia and the tendon binding muscle to bone

Answer 2

epimysium

Question 3

def: surrounds fascicles

Answer 3

perimysium

Question 4

def: surrounds muscle fibres, connective tissue that rests on a basement membrane

Answer 4

endomysium

Question 5

def: cells that lie deep to the endomysium but superficial to the sarcolemma

Answer 5

satellite cells

Question 6

________ constitute about 80% of myocyte volume

Answer 6

myofibrils

Question 7

how can you identify different myofibrils in longitudinal section?

Answer 7

they are slightly out of alignment of each other

Question 8

def: includes both thick and thin filaments, consists of contractile protein arrays bundled within myofibrils

Answer 8

myofilaments

Question 9

def: contains 200-500 molecules of myosin

Answer 9

thick filament

Question 10

def: contains F-actin, tropomyosin, and troponin

Answer 10

thin filament

Question 11

def: dark overlapping region of thick and thin filaments

Answer 11

A bands

Question 12

def: area with no filament overlap, thick filaments only, no cross bridges

Answer 12

H zone

Question 13

def: light thin filaments plus titin

Answer 13

I bands

Question 14

def: dark, mark the ends of the sarcomere and anchor thin filaments

Answer 14

Z bands

Question 15

def: connects the Z band to the M line

Answer 15

titin

Question 16

irrespective of the degree of contraction of the muscle fibre, the ______ ______ remains constant in width, while the __ and __ bands narrow in contraction to pull the ____ lines closer together

Answer 16

A band, I and H bands, Z lines

Question 17

def: thick filaments with fine interconnections

Answer 17

M line

Question 18

def: slow, red oxidative fibres, many mitochondria, abundant myoglobin, derive energy from aerobic oxidative phosphorylation of fatty acids, adapted for slow contractions over prolonged periods, small in transverse

Answer 18

Type I

Question 19

def: fast, intermediate oxidative-glycolytic fibres, derive energy from aerobic oxidative phosphorylation of fatty acids and anaerobic glycolysis, adapted for rapid contractions and short bursts of activity, large transverse section

Answer 19

Type IIa

Question 20

def: fast, white glycolytic fibres, relatively few mitochondria, less myoglobin, derive energy mostly from anaerobic glycolysis, rapid contractions and fatigue very quickly, large in transverse

Answer 20

Type IIb

Question 21

how is MHC I expressed in IHC?

Answer 21

in green

Question 22

how is MHC IIa expressed in IHC?

Answer 22

red

Question 23

what kind of training induces a more oxidative quadriceps muscle phenotype?

Answer 23

endurance training

Question 24

cardiac muscles are branched and joined end to end and side to side by ________________ ________-

Answer 24

intercalated disks

Question 25

where are nuclei in cardiac muscle located?

Answer 25

centered

Question 26

def: modified cardiac myocytes, scattered along the inner part of the myocardium adjacent to the endocardium

Answer 26

purkinje fibers

Question 27

purkinje are ______ and contain ________ stores

Answer 27

large and contain glycogen

Question 28

do smooth muscle fibers have sarcomeres?

Answer 28

no