Chapter 1 Structure and Function of Exercising Muscle

Question 1

What are the three main types of muscle?

Answer 1

Smooth, Skeletal, Cardiac

Question 2

Smooth muscle and cardiac muscle are under what type of control?

Answer 2

involuntary control

Question 3

Skeletal muscle is under what type of control?

Answer 3

Voluntary control

Question 4

The most external layer of a muscle is covered by what connective tissue?

Answer 4

Epimysium

Question 5

What are specific bundles within a muscle called?

Answer 5

Fascicles

Question 6

What are the connective tissues surrounding fascicles?

Answer 6

Perimysium

Question 7

Once past the perimysium and inside of a fascicle there are?

Answer 7

Muscle fibers

Question 8

The connective tissue surrounding muscle fibers is?

Answer 8

Endomysium

Question 9

Each muscle fiber is surround by a plasma membrane called??

Answer 9

Plasmalemma

Question 10

The plasmalemma and the basement membrane in the muscle fiber make up the?

Answer 10

Sarcolemma

Question 11

The Plasmalemma has many functions including…

Answer 11

1. having folds that keep the muscle from stretching too far and disrupting the plasmalemma
2. assists in transmission of action potential from motor neuron to muscle fiber

Question 12

Satellite cells are located between the? Their function is to?

Answer 12

Plasmalemma and the basement membrane. Involved in growth and development of skeletal muscle as well as adaptation to injury, immobilization, and training.

Question 13

The fluid between muscle fibers is called the?

Answer 13

Sarcoplasm

Question 14

The Sarcoplasm is composed of …

Answer 14

dissolved proteins, minerals, glycogen, fats, and organelles.

Question 15

How does the Sarcoplasm differ from cytoplasm?

Answer 15

large amount of glycogen stores and myoglobin stores which is an oxygen binding protein.

Question 16

extensions of the plasmalemma that pass through the muscle fiber are?

Answer 16

Transverse tubules

Question 17

Transverse Tubules are? fxn?

Answer 17

interconnected and pass among the myofibrils. They allow for nerve impulses received by the plasmalemma to be transferred to individual myofibrils.

Question 18

Tubules that run perpendicular to transfer tubules and run parallel to myofibrils are called?

Answer 18

sarcoplasmic reticulum

Question 19

The sarcoplasmic reticulum fxn is?

Answer 19

To store calcium for muscle contraction

Question 20

Each muscle fiber contains several thousand ?

Answer 20

myofibrils

Question 21

The myofibrils contain the contractile unit of the muscle and the basic unit of the myofibril its is called the?

Answer 21

sarcomere

Question 22

two protein filaments that are in the myofibrils and are considered the contractile units in the muscle

Answer 22

actin, myosin

Question 23

The thin filaments are?

Answer 23

Actin, troponin, tropomyosin

Question 24

The thick filaments are?

Answer 24

myosin

Question 25

The I band is?

Answer 25

light, thin filaments

Question 26

The A band is ?

Answer 26

Dark, thin and thick filaments

Question 27

The H zone is?

Answer 27

In the center of the A band, only seen in a relaxed muscle, thick filaments

Question 28

M-line is

Answer 28

in the middle of the H zone. composed of proteins for thick filaments to attach and stabilize the sarcomere

Question 29

Z disk

Answer 29

where sarcomeres connect end to end. Made up of proteins. There are two additional proteins nebulin and titian which provide points of attachment and stability for thin filaments.

Question 30

Titin

Answer 30

connects myosin from M-line to Z disk to stabilize it.

Question 31

Each thin filament is composed up of?

Answer 31

actin, tropomyosin, troponin

Question 32

Actin

Answer 32

Is the backbone of the thin filament. Made up by globular proteins and actin molecules that are in helical pattern.

Question 33

Tropomyosin

Answer 33

tube shaped protein that twists around actin.

Question 34

Troponin

Answer 34

attached to both tropomyosin and actin regularly.

Question 35

Tropomyosin and troponin due what?

Answer 35

They work with calcium ions to either relax or contract myofibrils.

Question 36

Nebulin

Answer 36

is an anchoring protein for actin, mediates myosin and actin interaction.

Question 37

Alpha motor neuron

Answer 37

nerve cell that connects with and innervates many muscle fibers

Question 38

Motor unit

Answer 38

all the muscle fibers that are signaled by one alpha motor neuron.

Question 39

sliding filament theory

Answer 39

1. action potential is sent from brain
2. AP travels down an alpha motor neuron to the axon terminal.
3. AP causes the release of ACh at the synaptic cleft via secretory vessicles.
4. Ach attaches to receptors on the plasmalemma causing a depolarization that travels down the T-tubule. The terminal cisternae release Ca2+
5. Ca2+ flows into the sarcoplasmic reticulum to the sarcomere.
6. Ca2+ attaches to troponin and causes the release of tropomyosin and actin.
7. Myosin attaches to actin and the cross bridge is formed.
8. ATP is hydrolyzed into ADP+Pi causing the power stroke of myosin pulling actin in
9. ATP resynthisizes and causes the release of the myosin head.
10. Completion of contraction occurs when Ca2+ is returned to the Sarcoplasmic reticulum.

Question 40

Type 1 fibers

Answer 40

are slowing to contraction, small muscle fiber, good aerobic endurance, produce a lot of ATP with oxygen, carbs, and fats, used in low intensity training

Question 41

Type 2 fibers

Answer 41

are faster to contraction, large muscle fiber, poor aerobic endurance, produce a alot of force, ATP produced without oxygen, high intensity training.

Question 42

ATPase

Answer 42

enzyme that breaks ATP bonds for energy.

Question 43

Eccentric

Answer 43

muscle lengthens while exerting force, maximal force produced is fast

Question 44

Concentric

Answer 44

muscle shortens while exerting force, maximal force production is slow

Question 45

Isometric

Answer 45

muscle tension is same as outside force

Question 46

motor recruitment order

Answer 46

Type I, Type IIa, Type IIx