movement and muscles part 3

Question 1

Contractile filament

thick filament is composed of what?

Answer 1

polymer of myosin

approx 300 myosin 2 hexamer

Question 2

Contractile filament

what is thin filament composed of?

Answer 2

polymer of alpha- actin

Question 3

Contractile filament

what are the ends of thin filament capped in?

Answer 3

tropomodulin

Question 4

Contractile filament

what is thin filament stabalized by?

Answer 4

Capz

Question 5

The two main types of muscle are based on what?

Answer 5

smooth and striated and are based on the arrangement of actin and myosin

Question 6

Striated muscles characteristics?

Answer 6

used for movement

skeletal/cardiac

actin/myosin in parallel

Question 7

smooth muscles characteristics?

Answer 7

used for digestion

vasoconstriction

actin/myosin not in parallel

Question 8

Where are myofibrils found?

Answer 8

in skeletal muscles

Question 9

Where are cardiomyocytes found?

Answer 9

in the cardiac muscles

Question 10

In striated muscles how are the filaments arranged?

Answer 10

thick and thin filaments arranged in sarcomeres

repeated in parallel and series

Question 11

What are Z-disks?

Answer 11

forms boarder of each sarcomere

thin filament is attached to z disk

titin attached

capz

Question 12

Where is capz located and what does it do?

Answer 12

attached to z disk and (+) end of the actin and will prevent polymerization and depolarization

Question 13

What is the A-band?

Answer 13

anisotropic band

middle region of sarcomere occupied just with thick filament

Question 14

What is the I-band?

Answer 14

(isotropic band)

locatedon either side of the Z-disk

occupied by thin filament

Question 15

What is the M-line?

Answer 15

located where the myosin 2 filaments join together

Question 16

how many times do thick and thin filament overlap in each sarcomere?

Answer 16

2x

Question 17

each thick filament is surrounded by how many thin ones?

Answer 17

six

Question 18

What is Nebulin?

Answer 18

stabalizing protein that runs along the length of thin filament

Question 19

What is titin?

Answer 19

secures the thin filament to the Z-disk

keeps the thick filament centered in sarcomere

very large and acts like a spring

Question 20

What is isotonic contraction?

Answer 20

some load but length of muscle changes ex. moving flexed limb

Question 21

What is isometric contraction?

Answer 21

contract but do not change in distance

ex. ab muscles, change tension but do not change in distance

change load on muscles