Ch 10 Muscular tissue (Wiley)

Through aerobic respiration in the mitochondria, one glucose molecule can create

30 or more ATP

What energizes the myosin head?

ATP hydrolysis reaction

The outermost layer of connective tissue surrounding a skeletal muscle is the

epimysium

The site where a somatic motor neuron releases acetylcholine to stimulate a skeletal muscle fiber is called the

neuromuscular junction

Skeletal muscle is covered, surrounded and protected by various layers of connective tissue. Which layer of connective tissue would surround a bundle of muscle fibers (muscle cells)?

perimysium

Which type of muscle tissue is involuntary (can't be consciously controlled)?

smooth muscle and cardiac muscle

During the contraction cycle, ATP attaches to

myosin

Mitochondrial activity in skeletal muscle cells are usually efficient, but can have limited ATP production if

there is limited O2 availability

Which portion of this myogram shows a single twitch of the muscle?

A

On the diagram, what structure is composed of the three connective tissue layers that extend past the muscle?

A. (tendon)

A runner nearing the end of a marathon race would produce most ATP by: A.aerobic respiration. B.anaerobic respiration C.creatine phosphate D.amino acid breakdown

B. aerobic respiration

All of the muscle fibers within the muscle are fully contracted and are in sustained contraction with no individual twitches detected due to high frequency of stimulation.

D

Which correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction? A. sarcolemma, axon of neuron, T tubules B. myofibrils, myofilaments, mitochondria C. T tubules, sarcolemma, myofilament D. muscle fiber, axon of neuron, myofibrils E. axon of neuron, sarcolemma, T tubules

E. axon of neuron, sarcolemma, T tubules

Muscular tissue has several important properties, such as electrical excitability. Another property of muscular tissue is that it is able to stretch, and return to its original size and shape. Which property of muscular tissue is this?

Elasticity

Which property of muscle gives it the ability to stretch without damage?

Extensibility

Which of the structures in the figure is the contractile organelle that contains the thick and thin filaments?

F. (myofibril)

In the diagram, where would you find stored Ca2+?

F. (sarcoplasmic reticulum)

Myasthenia Gravis is an autoimmune disorder that targets the ACh receptors at the NMJ and ultimately reduces the number of available receptors. Predict what happens if you treat the patient with a drug that inhibits the activity of acetylcholinesterase?

The drug will increase contraction.

Creatine phosphate reserves are restored via phosphorylation by ATP during rest. True or False

True

Energy can be transferred in the muscle cell through the conversion of ATP into ADP. True or False

True

In motor unit recruitment, the number of active motor units increases. True or False

True

Which of the following is directly responsible for transmitting an action potential from a motor neuron to a skeletal muscle fiber?

acetylcholine #5

Muscle fibers produce ATP using: A. creatine phosphate, B.anaerobic cellular respiration, C. aerobic cellular respiration

all of the choices are correct

The general functions of muscle tissue include which of the following? storage and movement of substances through the body. stabilization of body positions. production of body movement. heat generation.

all of the choices are correct.

Which ATP production would be sufficient to run in place for one minute?

anaerobic cellular respiration

________ released from the sarcoplasmic reticulum bind to troponin to trigger exposure of binding sites on actin and begin the contraction cycle. ______ supplies energy to detach the myosin head from actin.

calcium ions; ATP

Contraction of myofibrils within a muscle fiber begins when what is released?

calcium is released from the sarcoplasmic reticulum

[Refer to the diagram to help you with this question.] When a person is hooked up to a machine that will record myograms, a record of their muscle activity can be produced (depending on the frequency and strength of the stimuli that generate an action potential in their muscle tissue). If the person receives a series of multiple stimuli in a short period of time, the wave of muscle activity that will be recorded will show a sustained contraction with no period of relaxation in between the periods when they receive the stimuli. The myograms has recorded:

fused (complete) tentanus

After the fusion of myoblasts, the muscle fiber loses its ability to do what?

go through mitosis

Which term describes a somatic motor neuron and all the skeletal muscle fibers it stimulates?

motor unit

Which of the following molecules found in skeletal muscle cells binds oxygen that can later be used during aerobic metabolism to help generate ATP?

myoglobin

Cross bridges are formed during muscle contraction when _____ binds to _____.

myosin; actin

In a neuromuscular junction, the effect of acetylcholine (ACh) binding to receptors on the motor end plate lasts only briefly due to

rapid destruction of ACh in the synaptic cleft by acetylcholinesterase.

Skeletal muscle contraction is triggered to begin when calcium is released from?

terminal cisterns of sarcoplasmic reticulum

Which protein does Calcium bind to?

troponin

A brief contraction of all muscle fibers in a motor unit in response to a single action potential moving down the somatic motor neuron is known as

twitch contraction