Anatomy Quiz 4

Posture is maintained by _____ fibers. a. slow oxidative (SO) b. fast glycolytic (FG) c. type II d. white e. fast-twitch

a. slow oxidative (SO)

Which of the following is considered to be the "functional unit" of skeletal muscle fibers? a. the sarcomere b. the Z disc c. the myofilaments d. the sacroplasmic reticulum e. the neuromuscular junction

a. the sarcomere

When a muscle joins a bone and has no visible tendon, it is said to have a. an aponeurosis b. an indirect attachment c. a direct attachment d. a retinaculum e. a hidden insertion

c. a direct attachment

Which of the following is voluntary muscle? a. smooth muscle b. cardiac muscle c. skeletal muscle d. All of the choices are correct. e. None of the choices are correct.

c. skeletal muscle

What type of embryological cell gives rise to muscle fibers? a. myotomes b. mesoderms c. somites d. myoblasts e. satellite cells

d. myoblasts

Slow oxidative (SO) fibers (slow-twitch fibers) have more ______ & less ______ than fast glycolytic (FG) fibers (fast-twitch fibers). a. glycogen, myoglobin b. ATP, mitochondria c. lactic acid, ATP d. myoglobin, glycogen e. capillaries, mitochondria

d. myoglobin, glycogen

A motor unit is a. one neuromuscular junction b. the distance from one Z disc to the next c. one thick filament & all thin filaments w/ which it forms cross bridges d. one neuronal axon & all the muscle fibers innervated by it e. one myofibril of a muscle fiber

d. one neuronal axon & all the muscle fibers innervated by it

What structure stores calcium ions that trigger contraction? a. mitochondria b. myofibrils c. T tubules d. sarcoplasmic reticulum e. synaptic vesicles

d. sarcoplasmic reticulum

Which is not a function of skeletal muscle? a. movement b. heat production c. stability d. communication e. All of these are functions of skeletal muscle.

e. All of these are functions of skeletal muscle

Which of the following is an autoimmune disorder that leads to destruction of acetylcholine receptors? a. Duchenne muscular dystrophy b. atrophy c. crush syndrome d. Rhabdomyoma e. Myasthenia gravis

e. Myasthenia gravis

Each end of a sarcomere is marked by a. terminal cisternae b. an I band c. an H band d. an A band e. a Z disc

e. a Z disc

In contrast to skeletal muscle, smooth muscle has all of the following properties except a. one nucleus in each cell b. a lack of striations c. a lack of Z discs d. ability to regenerate through the process of mitosis e. an increased number of T tubules

e. an increased number of T tubules

Action potentials are propagated from the surface to the interior of a muscle fiber by way of a. the sarcomeres b. the sarcoplasmic reticulum c. the endomysium d. the myofibrils e. the T tubules

e. the T tubules