Muscle Ultratissue

Question 1

Types of muscle

Answer 1

Skeletal, cardiac, smooth

Question 2

Skeletal muscle is…

Answer 2

Striated muscle which is under voluntary control of the somatic nervous system

Question 3

Cardiac muscle is

Answer 3

Striated muscle found only on the heart

Question 4

Smooth muscle is…

Answer 4

Non-striated muscle which is controlled involuntarily by the autonomic nervous system

Question 5

Cell surface membrane of muscle cell

Answer 5

Sarcolemma

Question 6

T-tubules are…

Answer 6

Invaginations of the sarcolemma which conduct charge when a cell is depolarised

Question 7

Sarcoplasmic reticulums are…

Answer 7

Specialised endoplasmic reticulums which contain large storages of calcium ions

Question 8

Hierarchy of muscle organisation

Answer 8

Muscle fibres -> fascicles -> muscle

Question 9

Muscle fibres are surrounded by

Answer 9

Endomysium

Question 10

Muscle Fascicles are surrounded by

Answer 10

Perimysium

Question 11

Muscles are surrounded by

Answer 11

Epimysium

Question 12

Functional unit of muscle

Answer 12

Sarcomere

Question 13

Z line

Answer 13

Actin filaments are anchored

Question 14

M line

Answer 14

Where myosin filaments are anchored

Question 15

I band

Answer 15

Contains only actin filaments

Question 16

A band

Answer 16

Length of a myosin filament - may contain actin also

Question 17

H zone

Answer 17

Only myosin

Question 18

Thin filament

Answer 18

Actin

Question 19

Thick filament

Answer 19

Myosin

Question 20

Tropomyosin runs along…

Answer 20

The actin filament and blocks myosin head binding sites

Question 21

Troponin binds…

Answer 21

Tropomyosin to actin

Question 22

Troponin I

Answer 22

Binds to the actin filament

Question 23

Troponin T

Answer 23

Binds to Tropomyosin

Question 24

Troponin C

Answer 24

Binds to calcium ions

Question 25

1st stage of muscular contraction

Answer 25

Depolarisation arrives at neuromuscular junction. Conducted by T tubules - causes massive influx of calcium ions from sarcoplasmic reticulum

Question 26

2nd stage of muscle contraction

Answer 26

Calcium binds to Troponin C - causes Tropomyosin to move away from actin filament myosin head binding sites

Question 27

3rd stage of muscular contraction

Answer 27

Myosin heads bind to actin filaments. Power strokes cause the myosin heads to pivot in a rowing motion. This slides the actin filaments towards the M line

Question 28

4th stage of muscular contraction

Answer 28

ATP binds to myosin heads, causing them to unbind from actin

Question 29

What shortens during muscle contraction?

Answer 29

Distance between Z lines, I band, H zone and length of the sarcomere

Question 30

What stays the same during muscle contraction

Answer 30

A band and length of muscle filament

Question 31

Duchenne muscular dystrophy is when…

Answer 31

Dystrophin not produced - muscle fibres tear on contraction - muscle weakness

Question 32

Sufferers of duchenne muscule dystrophy are usually…

Answer 32

In a wheelchair by age 12