Muscular System

Question 1

Sarcolemma and plasma membrane

Answer 1

Sarcolemma- cell membrane

Plasma membrane- The sarcolemma

Question 2

Sarcomere

Answer 2

The functional unit of muscle fibers

Made of actin and myosin

Question 3

Actin vs Myosin structure an activity in muscle

Answer 3

Actin

Thin Filament (Act=Actor=thimottee chaleme= thin)

Actin contains myosin binding sites covered by regulatory proteins (green) until calcium ions are present.

Myosin

Thin Filament

Myosin molecules (purple) have a club-shaped (Mickey mouse club house) head that will extend toward and bind to actin (gray).

Question 4

Largest to smallest structures of skeletal muscle (5 structures)

Answer 4

Fascicle (FATTEST)
muscle fiber (MUSCLESSS)
myofibril (MYO=mayo will make u kinda big)
sarcomere,
myofilament (film= flimsey= weak = smol)

Question 5

4 Functions of the muscular system

Answer 5

1. movement of the body
2. maintaining posture and body position
3. Generating heat
4. Moving substances

Question 6

Calcium function during skeletal muscle contraction

Answer 6

Will expose the myosin binding site on Actin

Question 7

8. Mechanical force of contraction and actin filaments

Answer 7

Actin is sliding past the myosin

Question 8

9. Skeletal muscles cell and neurotransmitter junction structures

Answer 8

The end of each motor neuron branches into axon terminals (1).

Each axon terminal forms a junction with the sarcolemma (2) of a muscle cell.

Question 9

Skeletal muscle cell, sarcoplasmic reticulum, calcium

Answer 9

Calcium is storedin the sarcopasmic retiuclum

Question 10

Striations and myrofilaments

Answer 10

Striations are caused by the arrangement of micro filaments

Question 11

Acetylcholine and Skeletal muscles

Answer 11

Release when a nerve impulse reaches the axon terminal

Question 12

Acetylcholine, action potential, sodium

Answer 12

ACh causes temporary permeability to sodium to trigger skeletal muscle action potential

Question 13

Skeletal muscle twitch vs tetany

Answer 13

Twitch- brief and jerky

Tetany- prolonged contraction

Question 14

Creatine Phosphate, energy storage, ATP

Answer 14

ATP - Provides energy for muscle contraction

Generated in 3 ways:

Breakdown of creatine phosphate

Aerobic cellular respiration

Anaerobic glycolysis

Question 15

Isotonic vs. Isometric contraction w/examples

Answer 15

Isotonic- Isotonic contractions occur when the muscle shortens, and movement occurs

Examples: bicep curls, push-ups, pull-ups

Isometric- Isometric contractions occur when the muscles do not shorten; no movement occurs

Examples: Plank, Squats, Wall sits

Question 16

Skeletal muscle fatigue & ATP

Answer 16

Muscle fatigue is due to lack of ATP from consumption

Question 17

Anaerobic glycolysis and Muscles

Answer 17

Anaerobic glycolysis produces ATP

If the oxygen supply is depleted, the cells will utilize anaerobic glycolysis to produce a small amount of ATP. The byproduct of this process is lactic acid which leads to muscle soreness.

Question 18

Antagonist

Answer 18

Produces the opposite effect on the same bones (opposite of agonist)

Question 19

I band

Answer 19

band of sacromere with only actin filaments

Question 20

A band

Answer 20

Band with both actin and myosin

Question 21

Z discs and actin

Answer 21

Z dics allow for the attachement of the thin (actin) filiments, as well as an elastic protein.

Question 22

H zone

Answer 22

Just myosin

Question 23

Ions that signal “go” for muscle contraction

Answer 23

Calcium

Question 24

Where is Acetylcholine released?

Answer 24

By the motor end plates into the synaptic cleft

Question 25

Aerobic respiration requirement

Answer 25

Aerobic respiration requires oxygen (O2) to create ATP

Question 26

Extension

Answer 26

Extension- Increase angle of joint

Question 27

Rotation

Answer 27

Rotation- move bones around longitudinal axis

Question 28

Pronation

Answer 28

Pronation- when forearm rotation so palm faces posteriorly

Question 29

Flexion

Answer 29

Flexion- decrease angle of joint

Question 30

Abduction (aliens take you away)

Answer 30

Abduction – Move limb away from midline

Question 31

Sarcoplasmic reticulum and calcium

Answer 31

Sarcoplasmic reticulum stores calcium ions needed for contraction

Question 32

Frontalis (Muscle Action)

Answer 32

Raises eyebrows

Question 33

Orbicularis Oris

Answer 33

Closes moth and protrudes lips

Question 34

Masseter

Answer 34

Closes jaw and elevates mandible

Question 35

Sternocleidomastoid

Answer 35

Flexes the neck, rotates the head

Question 36

Pectoralis Major

Answer 36

Adducts and flexes the humerus

Question 37

Pectoralis Minor

Answer 37

Draws scapula down

Question 38

Rectus Abdominus

Answer 38

Flexes vertebral columb and compresses abdominal contents

Question 39

External Oblique

Answer 39

Rotate trunk and bend it laterally

Question 40

Deltoid

Answer 40

Arm abduction

Question 41

Biceps Brachii

Answer 41

Supinates forearm, flexes elbow

Question 42

Triceps brachii

Answer 42

Elbow extension

Question 43

Biceps femoris

Answer 43

Knee, internal and external rotation and hip extension

Question 44

Sliding filament theory of muscle contraction steps

Answer 44

Nerve impulse reaches the axon terminal Acetylcholine (Ach) is released into synapse ACh crosses synapse & binds to receptors on sarcolemma ACh causes change in membrane permeability; Action potential is generated Calcium ions are released from sarcoplasmic reticulum Ca2+ binds to regulatory proteins on actin, exposing binding sites for myosin Myosin heads bind to actin forming crossbridges Actin filaments are pulled toward center of the sarcomere The sarcomere shortens and the muscle contracts