Bio Unit #

A common site on the lower limb for injections is the

Gluteus Maximus

Identify the statement concerning skeletal muscle that is true.

It is responsible for locomotion.

List the following structures in order from smallest to largest.(1) Muscle fiber(2) Myofilament(3) Myofibril(4) Muscle fascicle

2,3,1,4

The capacity of a muscle cell to shorten forcefully is known as

Contractility

If Na+ cannot enter a muscle fiber in response to a stimulus,

Contraction cannot occur

When you "pull your tummy in" and compress your abdomen, you use the rectus abdominis, external abdominal oblique, internal abdominal oblique, and transversus abdominis muscles. This is an example of muscles working as

synergists

Muscles that elevate the jaw and close the mouth include the

temporalis and digastric

Which of the following muscles is part of the rotator cuff

teres major

A sustained muscle contraction is known as

tetanus

Sarcoplasm is the

cytoplasm of a muscle fiber

The adductor longus is named for its

function and size

The largest buttocks muscle is the

gluteus maximus

The biceps femoris is part of the

hamstring muscles

Troponin

has a calcium-binding site.

Raising the eyebrows is the action of the

occipitofrontalis

A sarcomere extends from

one Z disk to an adjacent Z disk

The digastric muscle is involved in

opening, mouth

The brachioradialis is named for its

origin and insertion

The sternocleidomastoid muscle extends from the mastoid process of the temporal bone to the sternum and medial clavicle. When both sternocleidomastoid muscles contract, the head is flexed. The end of the muscle that connects to the sternum is the

originally

Skeletal muscle fibers

possess striations

When an intramuscular injection is given in the anterior aspect of the thigh, the injection is in the

rectus femoris

After contraction has occurred, the Ca2+ are

released from troponin.

Tubules are invaginations of the

sarcolemma

Fascicle

surrounded by perimysium

Arrange the following list of biochemical events in the correct sequence.(1) An action potential is conducted deep into the muscle fiber by the T tubule.(2) Calcium ions bind to troponin.(3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions.(4) Calcium ions diffuse into the sarcoplasm around the myofibril.(5) The troponin-tropomyosin complex moves exposing active sites.

1,3,4,2,5

The region of the sarcomere that contains both actin and myosin myofilaments is called the

A Band

In which of the following situations does a resting membrane potential exist?

A relaxed Muscle Fiber

Synaptic vesicles in the neuromuscular junction contain

Acetylcholine

Which of the following is part of a thin myofilament?

Actin

A stimulus either causes an action potential or it doesn't. This is called

All or none response

Which of the following statements regarding the sliding filament model is false

Both actin and myosin myofilaments shorten during contraction.

Which of the following statements regarding the sliding filament model is false?

Both actin and myosin myofilaments shorten during contraction.

Acetylcholine is released from the presynaptic terminal by the process of

Exocytosis

Which of the following changes would have the most dramatic effect on the membrane potential?

Increased permeability of the membrane to Na+

Which of the following causes an unequal ion concentration across the resting plasma membrane?

Negatively charged proteins not readily diffusing across the plasma membrane

he type of muscle that functions as a sphincter is

Orbicular

The type of muscle that can contract with the greatest force is the

Pennate

Which of the following muscles is named for its location?

Quadriceps Femoris

Arrange these structures as they participate in excitation-contraction.

Sarcolemma, T tubules, sarcoplasmic reticulum, Ca2+

Which type of muscle tissue is under voluntary neural control?

Skeletal Muscle

The muscle shape that has the capacity to shorten to the greatest degree is

Straight

Which of the following is NOT a property of the myosin head?

They bind to Troponin

Which of the following muscles is named for its shape?

Trapezius

An antagonist

a muscle working in opposition to another muscle

When an action potential reaches the presynaptic terminal,

acetylcholine moves into the presynaptic terminal.

The active sites to which cross-bridges attach are found on the

actin myofilaments

orbicularis oculi muscle

causes crow's feet wrinkles

Muscle myofibrils

contain myosin and actin myofilaments

A myofibril is the

contractile thread that extends the length of the muscle fiber

Facial muscles are unusual in that they

insert and sometimes originate on skin and connective tissue.

Which of the following muscles is involved in chewing gum?

masseter

Synergist

muscle that aids a prime mover in a movement and helps prevent rotation

ATPase is found in

myosin heads

Which of the following is mismatched?

myosin myofilaments - thin myofilaments

At rest, the inside of the sarcolemma is relative to the outside

negatively charged

When the myosin head flexes into a bend, pulling the actin filament along with it, this is called the

power stroke

The orbicularis oris muscle

puckers the mouth for kissing

Too much acetylcholinesterase causes

rapid degradation of acetycholine.

origin

stationary end of muscle

sarcoplasmic reticulum

stores calcium ions

Sarcomeres are

structural and functional unit of skeletal muscle

In order for muscle relaxation to occur,

the active sites on actin must be blocked.

What is a cross bridge?

the combination of myosin heads with active sites on actin molecules

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

the emotional state of an individual

The insertion is

the end that moves when the muscle contracts

The plasma membrane of an excitable cell is more permeable to K+ because

there are more leak ion channels for K+ than Na+.