Module 2 - Muscles

Question 1

What is the definition of a muscle?

Answer 1

Muscle is a group of muscle cells with the same origin, insertion, and function.

Question 2

How many skeletal muscles do we have?

Answer 2

650 skeletal muscles

Question 3

T/F: You will find muscle tissue in almost every organ.

Answer 3

TRUE

Question 4

How much of our average body weight is muscle?

Answer 4

35%

Question 5

T/F: Muscles need to be excited to contract

Answer 5

TRUE

Question 6

Is Muscle shortening a contraction?
Is Muscle lengthening a relaxation?

Answer 6

YES. Shortening = Contraction
Lengthening = Relaxation

Question 7

What are the 3 main types of muscle?

Answer 7

Skeletal muscle, Cardiac muscle, and Smooth muscle.

Question 8

Which muscle is striated and voluntary?

Answer 8

Skeletal muscle

Question 9

Which muscle is found in the attached to the Skeleton?

Answer 9

Skeletal Muscle

Question 10

Which muscle is found in the in the walls of hollow organs?

Answer 10

Smooth Muscle

Question 11

Which muscle is found in the heart?

Answer 11

Cardiac muscle

Question 12

Which type of muscle has no striations?

Answer 12

Smooth muscle

Question 13

What are Fasicles?

Answer 13

Bundles of muscle fibers (cells) wrapped with connective tissue (fascia)

Question 14

What are the thick filaments of muscle called?

Answer 14

Myosin

Question 15

What are the thin filaments of muscle called?

Answer 15

Actin

Question 16

Which filament is light? Which is dark?

Answer 16

Actin - Thin- Light
Myosin - Thick - Dark

Question 17

What is a Sarcomere?

Answer 17

contractile unit of muscle

Question 18

What is a contraction?

Answer 18

Cross-bridges between thin and thick filaments are formed

Question 19

T/F: Calcium must be present for cross-bridges to form and for contraction to occur.

Answer 19

TRUE

Question 20

What is the three step process for a muscle to contract?

Answer 20

1. Skeletal muscle gets excited by a nerve getting an electrical message from the brain.
2. The nerve sends calcium to the muscle
3. The calcium helps the muscle contract

Question 21

What is the principle source of energy for muscles?

Answer 21

ATP

Question 22

T/F: ATP is required for contraction and relaxation

Answer 22

TRUE

Question 23

What are the two types of contractions?

Answer 23

Isotonic contractions and Isometric contractions

Question 24

What is an Isotonic contraction: Does the muscle shorten? Force? Movement?

Answer 24

muscle shortens, maintains a constant force, movement occurs

Question 25

What is an Isometric contraction: Does the muscle shorten? Force? Movement?

Answer 25

muscle doesn't shorten, force is generated, no movement

Question 26

Which muscle is the fastest?

Answer 26

Skeletal Muscle

Question 27

Which muscle is moderate speed?

Answer 27

Cardiac Muscle

Question 28

Which muscle is very slow, partially contracted all of the time and rarely fatigues?

Answer 28

Smooth Muscle

Question 29

Why is exercise beneficial? (3)

Answer 29

1. it increases blood flow and oxygen availability to the brain. 2. increases growth factors that promote new brain cells and neuronal pathways in the brain. 3. increases levels of neurotransmitters which increases memory retention, information processing, and cognition.

Question 30

T/F: Cardiac and Smooth muscles are involuntary.

Answer 30

TRUE

Question 31

T/F: Cardiac and Smooth Muscles are able to contract entirely on their own in absence of nerve stimulation.

Answer 31

TRUE

Question 32

Cardiac muscles cells are joined by ______.

Answer 32

Intercalated discs

Question 33

T/F: Intercalated discs and gap junctions in cardiac muscle cells allow their electrical current to spread from one cell to the next very quickly.

Answer 33

TRUE

Question 34

What genetic disease causes muscle wasting and weakening?

Answer 34

Duchenne muscular dystrophy

Question 35

An infection of a deep wound by bacteria, Clostridium tetani can cause what disease?

Answer 35

Tetanus

Question 36

What is the degenerative disorder of the central nervous system that mainly affects the muscular system and movement?

Answer 36

Parkinson's Disease

Question 37

What causes muscle cramps?

Answer 37

dehydration and ion imbalances.