Chapter 9 Part C

Of the following muscle types, which has only one nucleus, no sarcomeres, and few gap junctions? A- skeletal muscle B- visceral smooth muscle C- multiunit smooth muscle D- cardiac muscle

Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped, ________. A- maximum force production would result because the muscle has a maximum range of travel B- ATP consumption would increase because the sarcomere is "trying" to contract C- no muscle tension could be generated D- cross bridge attachment would be optimum because of all the free binding sites on actin

What part of the sarcolemma contains acetylcholine receptors? A- end of the muscle fiber B- any part of the sarcolemma C- motor end plate D- part adjacent to another muscle cell

Although all the anatomical parts of muscle work together to give it it's characteristics, which of the following proteins listed below would be most associated with the characteristics of extensibility? A- acetylcholine receptors in the motor end plate B- elastic (titin) filaments C- potassium (K+) leak channels D- thick (myosin) filaments

Although all the anatomical parts of muscle work together to give it it's characteristics, which of the following proteins listed below would be most associated with the characteristics of excitability? A- elastic (titin) filaments B- acetylcholine receptors in the motor end plate C- actin of thin filaments D- the Na+-K+ pump

Although all the anatomical parts of muscle work together to give it it's characteristics, which of the following proteins listed below would be most associated with the characteristics of contractility? A- elastic (titin) filaments B- potassium (K+) leak channels C- voltage gated sodium channels D- thick (myosin) filaments

Oxygen starved tissues can release chemical signals into the blood that can change the diameter of nearby blood vessels delivering oxygen and nutrients to the tissues. In doing so the blood vessels will respond through vasodilation (widening of the vessel). Which muscle type is responsible for this vasodilation? A- striated muscle B- cardiac muscle C- smooth muscle D- skeletal muscle

Of the following items listed below, which is the best description for why skeletal muscle stores glycogen. A- Glycogen provides a smooth surface for filaments to slide on. B- Glycogen is part of muscles rigid supporting framework. C- The glycogen is an insulating layer that helps regulate body temperature. D- Skeletal muscle is a heavy consumer of energy.

During development embryonic cells will fuse to form muscle fibers. This will result in ________. A- the striations that appear in skeletal and cardiac muscle tissues B- multinucleated muscle fibers that can extend as long as 30 centimeters C- interlocking of cells that can prevent the filaments from sliding D- the coordination of nerve signals to muscle fibers

Approximately 80% of a muscle fiber's volume are the myofibrils. This characteristic reflects muscles ability to ________. A- store oxygen molecules that can be used in aerobic respiration B- generate and propagate action potential C- produce relatively high amounts of ATP D- produce movement through contractile force

A myosin molecule in the thick filaments can be considered a protein having a quaternary structural level. Which of the following best describes this structural level? A- Myosin is involved in the power stroke of muscle contraction. B- Myosin is a primary component within a myofibril. C- Myosin molecules consist of two heavy and to light polypeptide chains. D- Myosin has an ATP binding site, actin binding site and flexible hinge region.

Curare is a poisonous plant extract. Curare molecules have a chemical structure like the neurotransmitter ACh. Curare can bind to the ACh receptor site on the chemically gated ion channels in the motor end plate. Even though curare will bind to the receptor site it will not open the ion channel and no ions will pass through. What do you think the symptoms of curare poisoning would look like? A- Curare will only affect cardiac muscle, causing fibrillations of the heart. B- Smooth muscles will become stimulated causing quick movement of nutrients through the digestive system. C- Curare will only affect muscles with ACh receptors, paralyzing them. D- Muscles will respond too quickly and cause a severe tremor.

Myasthenia gravis is a disease that is believed to be caused by autoimmune disorder, resulting in the loss of ACh receptors at the motor end plate of muscle fibers. Which of the following is likely to be a symptom of myasthenia gravis? A- weakness of muscle B- seizures and uncontrollable muscle movement C- dehydration with headache D- coma and loss of voluntary muscle movement

Which of the following statements best illustrates the fact that skeletal muscle is voluntary muscle? A- Skeletal muscle is wrapped in several layers of connective tissue. B- The deepest layer being the endomysium. Skeletal muscle appears striated due to the structure of the sarcomeres. C- The shivering reflex aids in maintaining body temperature. D- Skeletal muscle fibers are innervated by somatic motor neurons.

If a muscle fiber were to suddenly and permanently stop producing ATP the fiber would no longer be able to actively transport calcium out of the cytoplasm (sarcoplasm) and the intracellular calcium concentration would rise. Which of the following would you expect to happen? A- Myosin would be able to bind to the exposed binding sites on thin filaments but it would not be able to detach. B- Calcium would be transported to the sarcoplasmic reticulum therefore contractions would cease. C- The fiber would twitch uncontrollably due to excessive calcium bound to troponin. D- No change would occur in a muscle that was relaxed to begin with.

When a sarcomere contracts and thin filaments move over thick filaments you would expect to see ________. A- the I bands to appear smaller B- the I bands to appear wider C- the A band to appear darker D- the H zone to appear wider

Addition of more myoglobin to a muscle fiber would have the largest effect on ________. A- fast oxidative and slow oxidative fibers B- fast glycolytic and fast oxidative fibers C- fast oxidative fibers only D- fast glycolytic fibers only

Exhaustion of glycogen storage within a muscle fiber would have the biggest effect on ________. A- fast oxidative fibers B- slow oxidative fibers C- fast glycolytic fibers D- both slow and fast oxidative fibers

Reduction in blood flow to a muscle fiber would have the greatest effect on ________. A- slow oxidative fibers B- fast glycolytic C- fast oxidative fibers D- both slow and fast oxidative

A potential benefit of recruiting slow oxidative fibers for contraction before recruiting fast oxidative and fast glycolytic fibers might be ________. A- his will help to allow for fine control with delicate contractile force with a small stimulus B- because they are slower to respond, slow oxidative fibers must be stimulated first in order to contract simultaneously with the faster fibers C- there is little to no benefit from recruiting slow oxidative fibers first and therefore it is in fact fast glycolytic fibers that will be recruited first D- recruiting slow oxidative fibers early helps to tire them out first so that they won't interfere with the more powerful contractions of fast glycolytic fibers

Addition of more mitochondria to a muscle fiber will have the least effect on ________. A- fast oxidative fibers B- both slow and fast oxidative fibers C- fast glycolytic fibers D- slow oxidative fibers

If given the exact same amount of ATP, which of the three fiber types would be able to contract for the longest amount of time? A- slow oxidative fibers B- both fast glycolytic and fast oxidative fibers C- fast oxidative fibers D- fast glycolytic fibers

The 100 meter dash is a quick and short run requiring explosive speed. On completion of the dash the runners will continue to breathe hard for several seconds to minutes even though they are no longer running. Which of the following is the best explanation for why this is so? A- The runners' use of stored oxygen, glucose and creatine phosphate is being replenished and this requires a prolonged increase of oxygen intake. B- Since the exercise was mostly aerobic exercise, the runners' bodies have not yet realized the run is over. C- Slow oxidative fibers are recruited last and have only started to work at completion of the run. D- The runners' fast oxidative muscles are so slow to utilize oxygen it only begins aerobic respiration by the time the run has finished.

Only ________ muscle cells are multinucleated.

The end of the muscle that is attached to the part of the body in motion when a muscle contracts is called the ________.

The enzyme ________ is present in the synaptic cleft. Its activity stops the neutotransmitters stimulation.

Which cells help repair injured skeletal muscle fibers and allows regeneration of dead skeletal muscle

Only ________ muscle cells commonly branch.

A smooth, sustained contraction from rapid stimulation is called ________.