Chapter 9/10

Extensibility

A muscle can stretch beyond its normal resting length and still contract.

threshold

A muscle fiber will respond to a stimulus when that stimulus reaches the _____ level.

Elasticity

A muscle recoils to its original resting length after having been stretched.

Excitability

A muscle responds to a stimulus.

contractility

A muscle shortens forcefully.

lactic acidosis

A waste product of anaerobic respiration in muscle cells is _____, which can then be used to make ATP through aerobic respiration pathways.

oxygen deficit; excess post-exercise oxygen consumption

During exercise, an individual experiences _____ due to aerobic respiration, and after exercise, this oxygen is replenished with _____.

tropomyosin

During muscle contraction, binding sites for myosin are uncovered by the movement of ____

troponin

During muscle contraction, calcium ions bind to

depolarization

During the _____ phase, the inside of the cell becomes positively charged.

repolarization

During the ______ phase, the membrane potential returns to its resting value.

the active sites on actin must be blocked

In order for muscle relaxation to occur

the active sites on actin must be blocked

In order for muscle relaxation to occur,

fast-twitch

Respond rapidly to nervous system stimulation

ATP

The actin-myosin bond is broken by the binding of _____ to the myosin head.

resting membrane potential

The charge difference across the plasma membrane of an unstimulated cell is called the

plantar flexion

The lateral leg muscles primarily evert the foot, but they can also aid in ....

isotonic contraction

The length of the muscle changes

Smooth muscle

The most widely distributed muscle type; involuntarily controlled

acetylcholine

The neurotransmitter at the neuromuscular junction is

neuromuscular junction

The point where the axon terminal synapses with the muscle fiber sarcolemma is called the

the emotional state of an individual

The type of muscle fatigue known as "psychological fatigue" is the result of

actin; myosin

Thin myofilaments are _____ myofilaments, and thick myofilaments are _____ myofilaments.

calcium ions

Uncovering binding sites for myosin on actin myofilaments involves troponin binding to ______

respiration, production of body heat, constriction of organs and vessels, maintenance of posture, fighting off infections, necessary movements for respiration, speaking, writing, typing, smiling, propulsion of food through the digestive system, beating the heart

What are the functions of the muscular system?

fascicle

What is a bundle of muscle fibers called?

biceps femoris

What muscle of the thigh is on the posterior side

gluteus maximus, gluteus minimus, gluteus medius, tensor faciae latae

What muscles are performing the medial rotation of the hip

flexed

When both sternocleidomastoid muscles contract, the head is

agonist

a muscle that accomplishes a certain movement

extensor indicis

a muscle that extends both the wrist and the index finger is the

antagonist

a muscle that opposes a muscle that accomplishes a certain movement

antagonist

a muscle working in opposition to another muscle

slow-twitch

break down ATP relatively slowly

voltage-gated ion channels

channels that open or close in response to changes in the electrical charge or voltage across the plasma membrane are called

slow-twitch

contain large amounts of myoglobin

down

contracting of the inferior recuts muscle directs the pupil to look ___

rotate the head toward the left

contracting the right sternocleidomastoid muscle would

sodium ions

depolarization of the cell membrane occurs when there is a rapid influx (inflow) of

fast-twitch

fatigue quickly

troponin

has a calcium-binding site

slow-twitch

high aerobic capacity

size of muscle fibers

hypertrophy of skeletal muscles from weight lifting is caused by an increase in the

triceps brachii

if a man exercises by doing push-ups every day, he would strengthen or enlarge which muscle?

synergist

members of a group of muscles working together to produce a movement

masseter and medial pterygoid

muscles that elevate the jaw and close the mouth include the

fixator

muscles that hold one bone in place relative to the body while a usually more

isometric contraction

no change in the length of the muscle

prime mover

one muscle of a group working together that plays the major role in accomplishing the movement

orbicularis oris

puckers the mouth for kissing

myoblasts

skeletal muscle develops from multinucleated cells called

are under involuntary control

smooth muscle and cardiac muscle are similar in that they both

sacromere

structural and functional unit of the skeletal muscle cell

fascia

surround individual muscles

extensor hallicus longus

the ____ muscle extends the big toe

sternocleidomastoid

the ____ muscle is the prime mover for flexion of the head at the neck

gastrocnemius; soleus

the bulge of calf is caused by the _____ and ______ muscles.

thumb

the extensor pollicis brevis moves the

origin

the fixed end of a muscle

diaphragm

the major movement produced during quiet breathing is accomplished by the ____

insertion

the mobile end of a muscle

sliding filament model

the model that describes the contraction of the muscle is called the

sartorius

the muscle that is used to cross the legs is the

flex the toes

the muscles of the posterior compartment of the leg can plantar flex and invert the foot, and can also ...

positively charged

the outside of the resting plasma membrane is ______ relative to the inside of the resting plasma membrane.

neuromuscular junctions

the sites where a chemical substance is transmitted from the presynaptic terminal of an axon to the postsynaptic membrane of a muscle fiber are called

mastoid process of the temporal bone to the sternum and medial clavicle

the sternocleidomastoid muscle extends from the

isometric contraction

the tension of the muscle increases during the contraction

isotonic contraction

the tension of the muscle remains constant during contraction

infraspinatus

the____ is part of the rotator cuff muscle group.

rapid degradation of acetylcholine

too much acetylcholinesterase causes

external abdominal oblique

which abdominal wall muscle is the most superficial of the oblique muscles?

orbicularis oculi

which muscle of the head wraps around the orbits

pectoralis minor

which muscle will depress the scapula or elevate the ribs

trapezius

which muscles moves the scapula?

vastus lateralis

which of the following is a part of the quadriceps femoris muscle group?

abductor pollicis longus

which of the following is found in the posterior group of forearm muscles?

biceps femoris

which of the following muscles would be considered an antagonist to the rectus femoris

aerobic respiration

yields as many as 36 ATP per glucose molecule metabolized

skeletal muscle

Constitutes 40% of the body's weight; voluntarily controlled

cardiac muscle

Found only in the heart; involuntarily controlled

fast-twitch

High glycogen concentration

increase; no change in the number of

Hypertrophy means that there is an _____ in the size of the muscle fibers, and there is usually _____ muscle fibers.

depolarization of the muscle cell membrane

Movement of sodium ions into the muscle cell at the neuromuscular junction causes

myoblasts

Muscle cells originate from

thick myofilament

Myosin is also known as the