Anatomy Ch 10 Wiley homework

A runner nearing the end of a marathon race would produce most ATP by:

aerobic respiration

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

anaerobic cellular respiration

Contraction of myofibrils within a muscle fiber begins when

calcium is released from the sarcoplasmic reticulum

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

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

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

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

smooth & cardiac

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

30 or more ATP

What energizes the myosin head?

ATP hydrolysis reaction

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

mitosis

_______ 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

The outermost layer of connective tissue surrounding a muscle is the

Epimysium

T or F? creatine phosphate reserves are restored via phosphorylation by ATP during rest

True

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

acetylcholine

Which correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction?

axon of neuron, sarcolemma, T tubules

Muscle fibers produce ATP using:

creatine phosphate, anaerobic cellular respiration, aerobic cellular respiration

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

extensibility

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) tetanus

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.

fused tetanus

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

during contraction cycle, ATP attaches to

myosin

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

myosin; actin

General functions of muscle tissue

production of body movement, stabilization of body positions, storage and movement of substances through the body, and heat generation

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

terminal cisterns of 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

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

there is limited O2 available

Which protein does Calcium bind to?

troponin

T or F? Energy can be transferred in the muscle cell through the conversion of ATP into ADP.

true

T or F? in motor unit recruitment, the number of active motor units increases.

true

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