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