Muscle Physiology

Question 1

type of striated muscle attached to the skeleton used to facilitate movment, by applying force to bones and joints by contractions

Answer 1

Skeletal Muscle

Question 2

type of involuntary mononucliated or uninucleated, striated muscle found exclusively within the heart.

Answer 2

Cardiac muscle

Question 3

type of non-striated muscle, found with the “walls” of hollow organs such as the bladder, uterus and gastro tract . lines the lumen of the body such as blood vessels

Answer 3

smooth muscle

Question 4

tiny blood vessels throuhgout the body that connect arteries and veins. form intricate network around body tissues in order to distribute oxygen and nutrients to the cells and to remove waste substances.

Answer 4

capillaries

Question 5

tubular network that surrounds each individual myofibril and acts as a storage site for calcium within the skeletal muscle

Answer 5

sarcoplasmic reticulum

Question 6

passes in a transverse manner from the sarcolemma across a myofibril of striated muscle, allowing depolarization of the membrane to quickly penetrate to the interior cell

Answer 6

T-tubules

Question 7

thin polarized membrane enclosing a striated muscle fiber

Answer 7

sarcolemma

Question 8

fine connective tissue sheath surrounding a muscle fiber

Answer 8

endomysium

Question 9

wave-like change in the electrical properties of a cell membrane, resulting from the difference, in electrical charge between the inside and outside of the membrane, causing the muscle cell to contract

Answer 9

action potential

Question 10

site at which nerve impulses are transmitted to muscles

Answer 10

neuromuscular junction

Question 11

smallest functional unit of a muscle fiber, composed of contractile myofilaments

Answer 11

sarcomere

Question 12

a protein complex found in both skeletal muscle and cardiac muscle that relays calcium sensitivity to muscle cells

Answer 12

troponin

Question 13

group of muscle protein that bind to molecules of actin and troponin to regulate the interaction of actin and myosin

Answer 13

tropomyosin

Question 14

motor neuron and all of the corresponding muscle fibers it innervates

Answer 14

motor unit

Question 15

serves as the major energy source within a cell to drive a number of biological processes such as muscle contractions and the synthesis of proteins

Answer 15

adenosine triphosphate (ATP)

Question 16

myosin head that projects from the surface of thick filaments that bind to the surface of a thin filament (actin) in the presence of calcium ions

Answer 16

cross bridge

Question 17

sustained skeletal muscle contraction due to repeated stimulation at a frequency which prevents relaxation

Answer 17

complete tetanus

Question 18

unconscious nerve impulses that maintain the muscles in a partially contracted state

Answer 18

muscle tone

Question 19

specialized muscle structure innervated by both sensory and motor neuron axons, functioning to send proprioceptive information about the muscle to the central nervous system in response to muscle stretching

Answer 19

muscle spindles

Question 20

kinesthetic receptors situated near the junction of muscle fibers and tendons which act as muscle-tension regulators

Answer 20

golgi tendon organs

Question 21

a type of muscle contraction in which the muscles apply enough force to overcome the resistive force so that it shortens as it contracts

Answer 21

concentric contraction

Question 22

type of muscle contraction in which the resistive force is greater than the force applied by the muscle so that the muscle lengthens as it contracts

Answer 22

eccentric contraction

Question 23

contraction in which the muscle tension is increased but the joint angle is not changed because the resistance cannot be overcome. also known as static contraction

Answer 23

isometric contraction

Question 24

largest diameter muscle fiber, characterized by anerobic metabolism and the greatest maximum tension

Answer 24

type 2b fibers

Question 25

large diameter muscle fiber, characterized by aerobic and anaerobic metabolism. high maximum tension

Answer 25

type 2a fibers

Question 26

smaller diameter muscle fiber characterized by aerobic metabolism and lower maximum tension

Answer 26

type 1 fibers

Question 27

oxygen-transporting protein of muscle, resembling blood hemoglobin in function

Answer 27

myoglobin

Question 28

Used to produce energy

Answer 28

Mitochondria

Question 29

N/a

Answer 29

Sliding filament Theory

Question 30

N/a

Answer 30

All or none principle

Question 31

Causes of short term fatigue (5)

Answer 31

Exhaustion of ATP/CP
Decreased muscle pH
Insufficient oxygen
Reduced enzyme activity 
Tubular system disturbance

Question 32

Causes of long-term fatigue (3)

Answer 32

Depleted glycogen and blood glucose levels

Damage to sarcoplasmic reticulum

Depletion of electrolyte ions

Question 33

Inability to produce force, due to intense exercise - occurring in CNS and PNS

Answer 33

Fatigue

Question 34

Period between repeated actions in an exercise; energy system specific, based on physical condition

Answer 34

Rest interval/rest period

Question 35

Period between exercise bouts (visits). Muscle fibers: replenish energy reserves, repair damage from force, return to pre-exertion levels

Answer 35

Recovery period