Unit 10 HTHS 1110

The quadriceps muscle group is named this because it has ____ origins (heads).

4

Which step is shown at "1"?

ACh released, binding to receptors

During the cross-bridge cycle, which of the following events energizes ("cocks") the myosin heads?

ATP hydrolysis

Which step is shown at "2"?

Action potential reaches T-tubule

Myofibrils are:

Contractile elements of the cell

Which step is shown at "6"?

Sarcoplasmic reticulum recaptures Ca2+

_______ are required for the muscle action potential to penetrate deep into a muscle fiber.

T Tubules

What are the structures marked "4"?

T-tubules (transverse tubules)

When muscle contraction occurs:

Z disks (lines) come closer together

The structure labeled "1" in this graphic of the contractile unit of a muscle is a/an:

Z line

A motor unit is:

a motor neuron and all of the muscle cells it innervates

All three types of muscle (skeletal, cardiac and smooth) contain the proteins ____________ and ____________ .

actin; myosin

Which of the following mechanisms provides ATP for muscle contraction?

aerobic oxidation of glucose

The tibialis anterior is ______________ to the _____________.

anterior; tibia

The muscle shown at "1" and "2" (one muscle) is the:(There are 22 muscles listed. Scroll down to see the complete list, which ends with triceps brachii.)

biceps brachii

Cardiac muscle fibers are __________________ while skeletal and smooth muscle are not.

branched

Muscle fatigue may result from:

decreased ATP

The insertion of the ________________ is the calcaneal (Achilles) tendon which inserts on the calcaneus.

gastrocnemius

The insertion of the ________________ is the femur.

gluteus maximus

Muscle fatigue may result from:

glycogen depletion

The muscle shown at "1" is the:(There are 12 muscles listed. Scroll down to see the complete list.)

hip adductor group

The quadriceps group consists of the rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis. This group's origin is the:

iliac spine and femur

The muscles shown at "1" and "2" have one name ("3"). That name is the:(There are 12 muscles listed. Scroll down to see the complete list.)

iliopsoas

The _______________ of the triceps brachii is at the olecranon process of the ulna (i.e. the "funny bone"), which is the moving, distal bone when the arm extends.

insertion

The attachment of a muscle to the bone it moves (usually distal) is called its:

insertion

Muscle cells in cardiac muscle are tightly bound together by desmosomes. In cardiac muscle, these specialized structures are arranged in regions with multiple, closely-spaced desmosomes called:

intercalated discs

The muscle shown at "1" is the:(There are 22 muscles listed. Scroll down to see the complete list, which ends with triceps brachii.)

masseter

The origin of the ________________ is the zygomatic arch.

masseter

Compared to skeletal muscle, cardiac muscle has:

more blood supply

Skeletal muscles exert force on tendons which in turn pull on bones or other structures resulting in ____________.

movement

In the power-stroke phase of the sliding-filament model, when a muscle contracts:

myosin heads attach to thin filaments

The origin of the trapezius is the:

occipital bone and cervical spine

In this graphic depicting the organization of a skeletal muscle fiber, what is number 6?

sarcolemma

What is the structure marked "1"?

sarcolemma

The area indicated by brackets and labeled "2" in this graphic of the contractile unit of a muscle is a/an:

sarcomere

The basic functional unit of a myofibril is the:

sarcomere

What is the structure marked "2"?

sarcoplasmic reticulum

Which description best fits the structure of cardiac muscle cells?

striated with one central nucleus

The muscle shown at "1" is the:(There are 14 muscles listed. Scroll down to see the complete list.)

subscapularis

The structure labeled "1" is:

tendon

The muscle shown at "3" is the:(There are 14 muscles listed. Scroll down to see the complete list.)

teres minor

Transmission of a nerve impulse to the terminal process of a somatic motor neuron results in:

the release of acetylcholine.

Susie Storrs leaves for a run on a cold day in December. After running a mile she stops because she feels warm and removes her jacket, tying it around her waist. What function of muscle tissue makes her feel warm?

thermogenesis

In muscles, myosin is the name given to the protein making up:

thick filaments

In muscles, actin is the name given to the protein making up:

thin filaments

In the power-stroke phase of the sliding-filament model, when a muscle contracts:

thin filaments move towards the M line, moving the Z discs closer together

The origin of the ________________ is the occipital bone and cervical spine.

trapezius

The insertion of the ________________ is the olecranon process ("funny bone") of the ulna.

triceps brachii

T tubules are:

tube-like structures that run perpendicular to myofibrils

The muscle shown at "1" is the:(There are 14 muscles listed. Scroll down to see the complete list.)

wrist flexors