Muscles & Movement

Question 1

Function of Bones

Answer 1

provide framework and stability for muscles, act as 3rd class levels to facilitate movement

Question 2

Ligament

Answer 2

tissue that connects bone to bone

Question 3

Tendon

Answer 3

tissue that connects muscle to bone

Question 4

Muscle

Answer 4

organ that provides force required for movement by moving one bone in relation to another

Question 5

Origin point

Answer 5

point where a muscle attaches to bone and the point that the muscle moves towards

Question 6

Insertion point

Answer 6

point where muscle attaches to bone that contracts towards the origin

Question 7

Antagonistic Muscles

Answer 7

muscles that have opposing actions of one another (ie. extensor muscles relax when flexor muscles contract)

Question 8

What does a flexor muscle do?

Answer 8

Shortens the angle

Question 9

What does the extensor muscle do

Answer 9

Lengthen the angle

Question 10

The bicep is a…

Answer 10

flexor muscle

Question 11

The tricep is a…

Answer 11

extensor muscle

Question 12

Cartilage

Answer 12

allows for easy movement and shock absorption by distributing load and being smooth

Question 13

Why doesn’t the body replace cartilage?

Answer 13

Because it isn’t vascularized

Question 14

Synovial Fluid

Answer 14

fluid in join that provides food, oxygen, and lubrication to cartilage and reduces friction between articular cartilage

Question 15

Joint capsule

Answer 15

part of the joint that seals joint space and provides passive stability by limiting range of movement

Question 16

Similarities between the hip and knee joint

Answer 16

1. Synovial joints (have synovial fluid)
2. Involved in movement of the leg

Question 17

What type of joint is the hip joint and how can it move?

Answer 17

Ball and socket joint, and it can extend/flex, abduct/adduct, and circumduct/rotate

Question 18

Abduction

Answer 18

movement away from body

Question 19

Adduction

Answer 19

movement towards body

Question 20

What type of joint is the knee joint and how can it move?

Answer 20

Hinge joint, and it can only flex/extend (angular direction of movement)

Question 21

What are myofibrils made of?

Answer 21

Actin and myosin

Question 22

Sarcomere

Answer 22

the basic contractile unit of the muscle

Question 23

Actin

Answer 23

thin filament that does the movement in the sarcomere

Question 24

Myosin

Answer 24

thick filament that stays put in the sarcomere

Question 25

I Band

Answer 25

consists of only actin

Question 26

A band

Answer 26

band that covers one end of the myosin to the other, including overlap with actin

Question 27

H Band

Answer 27

band that contains myosin only, no overlap

Question 28

M Band

Answer 28

midline of the sarcomere

Question 29

Z-disc

Answer 29

the edge of the sarcomere

Question 30

Myosin Club Heads

Answer 30

the part of myosin that grabs onto the actin and pulls it towards the middle

Question 31

What does the sarcoplasmic reticulum do?

Answer 31

it is where calcium is made and stored, because muscle contraction requires a lot of calcium

Question 32

Acetylcholine

Answer 32

neurotransmitter that signals muscle movement

Question 33

T-tubules

Answer 33

tubes that move all the way down the muscles that help with signal in muscle movement

Question 34

Troponin-tropomyosin complex

Answer 34

Complex that consists of troponin, a handle, and tropomyosin, which covers up the binding sites for actin and which is revealed in order for muscle contraction

Question 35

Ratchet Effect

Answer 35

the ability for the myosin club heads to form cross-bridges with the actin and pull it forward

Question 36

Acetylcholinesterase (AChE)

Answer 36

enzyme that gets rid of excess acetylcholine in the synaptic cleft which allows for muscle relaxation

Question 37

Process of Muscle Contraction

Answer 37

1. Acetylcholine enters neuromuscular junction
2. Acetylcholine opens up Na+ ligand-gated channels
3. Change in charge opens voltage-gated Ca2+ gates
4. Signal moves down T-tubules
5. Triggers Ca2+ release from sarcoplasmic reticulum
6. Ca2+ bind to troponin-tropomyosin complex
7. Conformational change reveals binding sites on actin, where troponin acts as a handle that pulls down the tropomyosin
8. Revelation of binding sites allows for formation of cross-bridge between myosin club heads and actin binding sites
9. Ratchet effect, where myosin pulls actin in, so it contracts