Muscle

Which of the following muscles compose the anterior abdominal wall?

1. Rectus abdominis 2. Transversus abdominis 3. External oblique 4. External oblique 5. Internal oblique

Which of the following are attachment points for the sternocleidomastoid muscle?

1. The medial third of the clavicle2. Mastoid process of the temporal bone3. Sternum

When a muscle fiber contracts, which parts of the sarcomere maintain a constant length throughout contraction?

A band

Glycolysis and aerobic respiration are used to generate ______ in muscle fibers.

ATP

Rectus abdominis

Abdominal wall muscles

Longissimus

Erector spinae

Muscle cells are said to have what characteristic because they can respond to stimulation from the nervous system?

Excitability

True or false: A muscle fiber that is partially shortened can produce a contraction stronger than the contraction it can produce when at its resting length.

False

Which of the following muscles is found in the posterior compartment of the leg?

Gastrocnemius

At maximal contraction of a muscle fiber, the thin filaments are pulled into the ______ zone which disappears.

H

In a relaxed muscle fiber there are no thin filaments overlapping the thick filaments in the ______ zone.

H

In a sarcomere, the ______ zone (or band) is the light, central region of the A band.

H

When viewed under a light microscope, the light bands, called ______ bands, contain only ______ filaments.

I; thin

If you strain to push on a wall that does not move, your muscles are in a type of ______________ contraction.

Isometric

The ______ line is a thin, transverse, protein meshwork structure in the center of the H zone of a sarcomere.

M

Deep invaginations of sarcolemma are called ______.

T-tubules

When calcium ions bind to troponin, which of the following then occurs?

The myosin-binding sites on actin are exposed

True or false: A single myofibril runs the length of the muscle fiber.

True

True or false: In the absence of calcium, troponin attaches to tropomyosin to hold it in place on the surface of the F actin strand.

True

True or false: Most muscles contain a combination of all three muscle types, slow oxidative, fast oxidative, and fast glycolytic

True

Which of the following proteins are found in a thin filament?

actin

Slow and intermediate fibers require oxygen to produce ATP, so the metabolic reactions within these fibers are termed ______.

aerobic

A broad, flat tendon

aponeurosis

Smooth muscle is found in which of the following locations?

around blood vessels in wall of the uterus in the wall of the small intestine

Smooth muscle is found where in the respiratory system?

around the bronchioles

Pertaining to the cheek

buccal

Which can cause muscle fatigue?

build up of intracellular Pi Na+ or K+ imbalances insufficient Ca2+

Functionally, troponin provides a binding site for ______ ions.

calcium

A muscle fiber is what level of organization in the body?

cellular

When smooth muscle is stretched, it responds by ______.

contracting then relaxing

Sarcoplasm is another term for skeletal muscle ______.

cytoplasm

The amount of additional oxygen that must be inhaled in order to restore pre-exercise levels is called oxygen _________

debt

The epimysium of a muscle is composed of ______ connective tissue

dense irregular

Muscle tissue demonstrates the property of _____ when it is done contracting and returns to its resting length.

elasticity

Digastric

elevates hyoid and depresses mandible

Covers a skeletal muscle fiber

endomysium

Covers an entire skeletal muscle

epimysium

The three connective tissue layers surrounding the individual components of a muscle are the _________ , ______________ , and ______________

epimysium, perimysium, and endomysium

An increase in joint angle

extension

Outside of

extrinsic

In a transverse section of a muscle, you can see that each skeletal muscle is actually composed of many __________which are bundles of muscle fibers.

fascicles

A piano player uses her hands for brief quick movements. Which muscle fiber type would you therefore predict to be predominant in these muscles?

fast glycolytic

In a normally functioning muscle, the inability to contract and produce tension is called muscle ___________

fatigue

Overall, as aging progresses, muscle strength and endurance are impaired, and the individual has a tendency to ______________ quickly.

fatigue

A skeletal muscle cell is also called a muscle

fiber

The actions of anterolateral abdominal wall muscles include rotation and __________ of the trunk.

flexion

Smooth muscle cells are ______ in shape.

fusiform

Smooth muscle is composed of short cells that have a ______ shape.

fusiform

Each myosin strand has a free ______ and an attached tail.

head

What part of a myosin molecule does ATP bind to?

head

If a muscle cell is stimulated to contract, allowed to partially relax, then stimulated again, its force of contraction the second time will be ______.

higher

In which activities are muscles in an isometric contraction?

holding a yoga pose sitting up very straight pushing on a locked door

The diameter of a muscle fiber will predict ______.

how much power it will produce

An increase in the number of mitochondria can be observed in ______.

hypertrophy

You make a New Year's resolution to work out more and by March notice your muscles are getting bigger. This is a result of muscle ______.

hypertrophy

Multiunit smooth muscle cells are stimulated ______.

individually

The "groin" region

inguinal

Cardiac muscle cells form Y-shaped branches and join to adjacent muscle cells at junctions called __________ discs.

intercalated

Cardiac muscle cells form Y-shaped branches and join to adjacent muscle cells at junctions called ___________ discs.

intercalated

When a nerve impulse reaches the end of an axon of a neuromuscular junction, calcium flows ______ the synaptic knob.

into

Smooth muscle contraction is under control of the ____________ nervous system.

involuntary

In order to predict how much tension a muscle can produce when contracting, it is important to consider the ______ relationship of thick and thin filaments.

length-tension

Because muscle cells require a huge amount of ATP in order to contract, they have a large number of which organelle?

mitochondria

Slow fibers have a relatively large number of ______. This permits slow muscle fibers to produce a greater amount of ______ than fast muscle fibers while contractions are underway.

mitochondria; ATP

Athletes have more defined muscles than non-athletes even while at rest because they have ______ motor units contracting all the time.

more

Athletes have more defined muscles than non-athletes even while at rest because they have ______ motor units contracting all the time. Multiple choice question. smaller

more

In a motor unit, a single _________ neuron typically controls numerous muscle fibers in a muscle.

motor

A motor unit is composed of a single ______ and all of the muscle fibers it controls.

motor neuron

A single motor neuron and the skeletal muscle fibers it controls is called a ______.

motor unit

What is the force generated when a skeletal muscle is stimulated to contract called?

muscle tension

After the age of 30, the number of ______ in existing muscle fibers decreases.

myofibrils

The sarcoplasm of a skeletal muscle fiber contains hundreds to thousands of long, cylindrical structures called ___________ that extend the length of the cell.

myofibrils

Muscle fibers contain cylindrical structures called myofibrils, which are composed of ______.

myofilaments

Myofibrils are made of ______.

myofilaments

Termination of the nerve impulse at an NMJ results in the passive sliding of ______ back to their original state.

myofilaments

Muscle cells store oxygen bound to a __________ molecule?

myoglobin

Muscle cells store oxygen bound to a ___________ molecule?

myoglobin

Thick filaments are assembled from bundles of the protein called

myosin

Thick myofilaments are composed of bundles of _______ protein molecules.

myosin

Thick myofilaments are composed of bundles of __________ protein molecules.

myosin

While observing skeletal muscle tissue under the microscope you note that it appears striated. You tell your lab partner this is because ______.

of the arrangement of myofilaments in each sarcomere

The plasma membrane of a skeletal muscle fiber is called the

sarcolemma

Within a myofibril, each ______ shortens as the muscle fiber contracts.

sarcomere

A contracting skeletal muscle fiber typically shortens as all of its ______ shorten in length.

sarcomeres

At the end of muscle contraction, calcium ions are moved back into the ___________ reticulum by ATP-driven ion pumps.

sarcoplasmic

Within a myofibril, Z discs separate the functional contractile units known as

sarcromeres

During the development of skeletal muscle cells, some myoblasts do not fuse and instead become ______ cells.

satellite

If a skeletal muscle is injured, surrounding _____ cells may be stimulated to differentiate and assist in its repair and regeneration.

satellite

Cardiac muscle cells are ______ and thicker than skeletal muscle cells, and they have only ______ nuclei.

shorter; 1-2

Approximately 40-50% of your body weight is _____ muscle.

skeletal

Attached to the skeleton and surrounding the openings of the urinary and gastrointestinal traces are locations of ______ muscle.

skeletal

Maintenance of posture and production of heat are functions of ______ muscle.

skeletal

Somatic motor neurons innervate ______ muscle.

skeletal

The ___________ filament theory explains how muscle fibers shorten during contraction.

sliding

Smooth muscle contraction is _____________ , resistant to ___________ , and usually sustained for an extended period of time.

slow; fatigue

Skeletal muscle contraction is controlled by __________ neurons

somatic

Skeletal muscle contraction is controlled by

somatic neurons

A "step-wise" increase in the force of contraction of a single muscle fiber or single motor unit due to repeated stimulation is called ____________

summation

The force generated when a skeletal muscle is stimulated to contract is muscle

tension

As a result of ACh stimulation, calcium ions are released from the ______ of the sarcoplasmic reticulum.

terminal cisternae

The epimysium of a muscle surrounds ______.

the entire skeletal muscle

Slow-twitch and fast-twitch muscle fibers differ primarily in

their ATPase which splits ATP

Slow-twitch and fast-twitch muscle fibers differ primarily in ______.

their ATPase which splits ATP

The H band (or H zone) is more lightly shaded because only __________ filaments are present.

thick

The H band (or H zone) is more lightly shaded because only ___________ filaments are present.

thick

in a sarcomere, the M line serves as an attachment site for the ______ filaments and keeps them aligned during contraction and relaxation.

thick

Single unit muscle cells contract ______.

together

As you sit there reading this your muscles, even your relaxed ones are not completely relaxed and soft. This is because they have some background tension called resting muscle ______.

tone

The deep invaginations of the sarcolemma that extend into the sarcoplasm of skeletal muscle fibers as a network of narrow membranous tubules are called ______.

transverse tubules

As the troponin changes shape (due to binding calcium), it moves the ______ molecule to which it is attached, thus exposing the active sites on the G-actin molecules.

tropomyosin

Calcium ions bind to what protein in a thin myofilament?

troponin

Upon release from the terminal cisternae, some calcium ions bind to ______ causing it to change shape.

troponin

Smooth muscle cells retains their mitotic ability.

true

A single contraction and relaxation of a muscle fiber is referred to as a muscle

twitch

Each myosin protein molecule in a thick filament consists of ______ strands.

two

Thick filaments are about ______ the diameter of thin filaments.

two times

Orbicularis oris

Muscles of facial expression

After you stop running, you notice that you keep breathing heavily for some time. This is because your body is in ______.

oxygen debt

Covers a fascicle

perimysium

As you hold a barbell and begin to flex your arm in a curl, your biceps brachii slowly lifts the weight by using more and more motor units. This phenomenon, which increases the strength of the contraction, is referred to as __________

recruitment

As you struggle to twist open a jar, more motor units are called into action until you finally generate enough force to open it. This is an example of ______.

recruitment

An internal membrane complex in skeletal muscle cells that is similar to the smooth endoplasmic reticulum of other cells is called the sarcoplasmic

reticulum

After stimulation of ACh receptors, a muscle impulse spreads quickly along the _______________ and into the muscle fiber along T-tubules.

sarcolemma

After stimulation of ACh receptors, a muscle impulse spreads quickly along the ________________ and into the muscle fiber along T-tubules.

sarcolemma