Week 10 - Muscle Anatomy

Question 1

muscle

Answer 1

bundles of fibre that can only stretch/contract in one direction

Question 2

movement accomplished by a muscle depends on:

Answer 2

type of joint, orientation of muscle fibres, action of other muscles, muscle tension

Question 3

abduction

Answer 3

moving a part away from the medial plane

Question 4

adduction

Answer 4

moving a part towards the medial plane

Question 5

supination

Answer 5

palm upwards

Question 6

pronation

Answer 6

palm downwards

Question 7

dorsiflexion

Answer 7

foot towards anterior tibia

Question 8

plantar flexion

Answer 8

foot away from tibia

Question 9

eversion

Answer 9

foot moves laterally (aka pronation)

Question 10

inversion

Answer 10

foot moves medially (aka supination)

Question 11

elevation

Answer 11

moving a part upwards

Question 12

depression

Answer 12

moving a part downwards

Question 13

protraction

Answer 13

outward on a plane parallel to the ground

Question 14

retraction

Answer 14

inward

Question 15

each muscle fiber (containing myofibrils) is surrounded by…

Answer 15

an endomysium layer

Question 16

a group of fibres (fascicle) is wrapped by…r

Answer 16

a perimysium layer

Question 17

a group of fascicles is wrapped by…

Answer 17

an epimysium

Question 18

sarcoplasmic reticulum

Answer 18

similar to the smooth ER, contains high levels of calcium ions

Question 19

Z line

Answer 19

separates one sarcomere from another

Question 20

I band

Answer 20

lighter portion of sarcomere that contains only the thin filaments

Question 21

A band

Answer 21

covers the whole length of the thick filament

Question 22

H zone

Answer 22

contains only thick filaments

Question 23

M line

Answer 23

the “middle line” of the sarcomere

Question 24

thick filaments

Answer 24

composed of several myosin molecules linked together

Question 25

thin filaments

Answer 25

actin, tropomyosin, troponin
-actin molecules twist together to form a thin filament with several myosin-binding sites
-myosin-binding sites are covered by a protein called tropomyosin
-tropomyosin is held in place by troponin

Question 26

what’s required for a muscle to contract?

Answer 26

calcium ions and ATP

Question 27

sources of ATP for muscle contraction

Answer 27

aerobic respiration, anaerobic respiration, creatine phosphate