Muscular system

Question 1

Cardiac muscle

Answer 1

Striated and involuntary, Makes up the wall of the heart.

Question 2

Smooth muscle

Answer 2

Smooth and involuntary, Found in other organs such as those of the digestive system

Question 3

Skeletal muscle

Answer 3

Striated, voluntary and fatigue easily. Attaches to bone, responsible for all movement. Most common muscle tissue in the human body)

Question 4

Sarcomere

Answer 4

The contractile unit of muscle tissue

Question 5

Z line

Answer 5

The lateral boundary of the sarcomere where the myofilament actin attaches.

Question 6

Glycogen

Answer 6

The stored form of glucose found in the liver and muscles

Question 7

Myofibrils

Answer 7

Parallel filaments that form muscle

Question 8

Myofilaments

Answer 8

The filaments of myofibrils composed of actin and myosin

Question 9

Actin

Answer 9

The thin filaments of muscle myofilaments where myosin binds to generate muscle contraction

Question 10

Myosin

Answer 10

The thick filaments of myofilaments with a fibrous head, neck, and tail that binds to actin.

Question 11

Endomysium

Answer 11

the connective tissue covering each muscle fiber.

Question 12

Epimysium

Answer 12

Fibrous elastic tissue that surrounds a muscle

Question 13

Fasciculi

Answer 13

Bundles of muscle fibers; the singular is ‘‘fascicle’’

Question 14

Perimysium

Answer 14

The connective tissue that covers a bundle of muscle fibers

Question 15

Tendon

Answer 15

A strong fibrous connective tissue that attaches muscle to bone

Question 16

Periosteum

Answer 16

a dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints

Question 17

Requirement for muscle contraction

Answer 17

Must receive a signal from the CNS

Question 18

Neuromuscular junction

Answer 18

the space between a motor neuron and muscle fiber

Question 19

Neurotransmitter

Answer 19

a chemical messenger that transmits messages between neurons or from neurons to muscles

Question 20

Acetylcholine

Answer 20

the neurotransmitter (unique to the motor neuron) released by an action potential at the neuromuscular junction

Question 21

Sliding-filament theory

Answer 21

the interaction of actin and myosin that describes the process of muscle contraction

Question 22

From what are muscles made of

Answer 22

Muscles are made up of sarcomeres—a contractile unit of a myofibril (muscle fiber)

Question 23

Size principle of fiber recruitment (also called Henneman’s size principle)

Answer 23

principle stating that motor units are recruited in order according to their recruitment thresholds and firing rates. In other words, motor units will be recruited in order from smallest and slowest firing rate to largest and fastest firing rate.

Question 24

muscle fiber Type I

Answer 24

slow-twitch fibers and aerobic (good for endurance)

Question 25

muscle fiber Type II

Answer 25

fast-twitch and anaerobic (good for power

Question 26

muscle fiber Type IIa

Answer 26

fast-twitch, moderately fatigable muscle fibers with moderate mitochondrial density

Question 27

muscle fiber Type IIx

Answer 27

fast-twitch, fast-fatigable muscle fibers with low mitochondrial density (white in color)

Question 28

Mitochondria (singular “mitochondrion”)

Answer 28

an organelle with a double membrane and many folds inside responsible for generating the chemical energy needed for biochemical reactions; the “powerhouse of the cell”

Question 29

How does muscle create movement

Answer 29

Muscles create movement by pulling on bones within the body.

Question 30

Origin

Answer 30

the proximal (closer to the midline of the body) attachment

Question 31

Insertion

Answer 31

the distal (farther from the midline) attachment

Question 32

Action

Answer 32

the specific movements that each muscle is responsible for

Question 33

Innervation

Answer 33

the specific distribution of nerves to a particular part of the body

Question 34

Fusiform muscle

Answer 34

spindle-shaped muscle Example: Biceps brachii

Question 35

Convergent muscle (triangular muscle)

Answer 35

muscle fibers converging from a broad origin (fixed point where the muscle attaches closest to the torso) to a single tendon of insertion (fixed point where the muscle attaches farthest from the torso) Example: Pectoralis

Question 36

Circular muscle

Answer 36

muscle fibers surrounding an opening in the body

Question 37

Parallel muscle

Answer 37

muscle fibers running parallel to the axis of the muscle Example: Stylohyoid

Question 38

Pennate muscle

Answer 38

muscles with fasciculi that attach obliquely (diagonally)

Question 39

Unipennate muscle

Answer 39

muscle fibers extending from one side of a central tendon Example: Flexor pollicis longus

Question 40

Bipennate muscle

Answer 40

muscle fibers extending from both sides of a central tendon Example: Soleus

Question 41

Multipennate muscle

Answer 41

muscle fibers extending from both sides of multiple central tendons Example: Deltoid

Question 42

Concentric

Answer 42

muscles that shorten to produce movement. For example, during the pressing motion of a bench press, the pectoralis is concentrically contracting.

Question 43

Eccentric

Answer 43

muscles that lengthen to allow movement. For example, during the downward motion of a biceps curl, the biceps brachii is eccentrically contracting. When applying tempo training, this is the part of the movement that should be the focus and, therefore, the slowest portion of the repetition.

Question 44

Isometric

Answer 44

muscles where the joint angle and muscle length do not change during movement. For example, the entire body works to maintain a stable position when performing a plank.

Question 45

Agonist

Answer 45

Main muscle responsible for movement; prime mover Example: Biceps brachii during a biceps curl

Question 46

Synergist

Answer 46

Muscle that plays a secondary role in movement Example: Brachioradialis during a biceps curl

Question 47

Antagonist

Answer 47

Muscle with an action directly opposite of the agonist Example: Triceps during a biceps curl

Question 48

All-or-none principle

Answer 48

The amplitude—or strength—of a nerve’s action potential is independent of the strength—or magnitude—of the stimulus

Question 49

Stretch-shortening cycle (SSC)

Answer 49

the cycling between the eccentric (stretch) action of a muscle and the concentric (shortening) action of the same muscle Three (3) phases: Eccentric, Amortization, Concentric