A&P H-A Ch.9

What is the cause of rigor mortis?

Calcium influx and lack of ATP

Which of the following provides the final "go signal" for contraction?

Calcium ions

Blood courses through your body because of the rhythmically beating cardiac muscle of your heart and the smooth muscle in the walls of your blood vessels, which helps maintain blood pressure.

True

Cardiac muscle is striated, but involuntary controlled. Smooth muscle is nonstriated and voluntarily controlled.

True

Cardiac muscle usually contracts at a fairly steady rate set by the heart's peacemaker, but neural controls allow the heart to speed up for brief periods, as when you race to your A&P exam.

True

Rigor mortis (death rigor) illustrates the fact that the cross bridge detachment is ATP driven. Most muscles being to stiffen 3 to 4 hours after death. ( this ones too long to type it all)

True

Skeletal muscle fibers are the longest muscle cells and have obvious stripes called striations.

True

The linking of thick and thin filaments together is called __________.

forming a cross bridge

Match the following description of muscle action with the correct term: Type of contraction represented by a single stimulus/contraction/relaxation sequence.

Twitch

"Cross bridges" that link between the thick and thin filaments directly involve ____________.

myosin

The space between the axon terminal of the motor neuron and the muscle fiber is called the _________.

synaptic cleft

When an action potential arrives at the neuromuscular junction, the most immediate result is __________.

the release of acetylcholine from the motor neuron

Acetylcholinesterase ______________.

breaks down acetylcholine

Match the following area with the correct term: Contains vesicles filled with acetylcholine.

Axon terminal

Which energy source provides high yields of ATP necessary for prolonged-duration exercise?

ATP is generated by breakdown of several nutrient energy fuels by aerobic pathway.

The thin myofilaments of skeletal muscle are composed chiefly of _________.

Actin

Which metabolic process involves an electron transport chain?

Aerobic

Which metabolic process will generate more ATP?

Aerobic

Where does 95% of the energy needed for contraction come from during moderate exercise?

Aerobic respiration

Which metabolic process will generate an acid?

Anaerobic

Match the follow description with the appropriate type of muscle: Usually contracts at a fairly rate and can contract without stimulation from the nervous system.

Cardiac muscle

Match the following description with the correct type of muscle: Striated and involuntary

Cardiac muscle

Select the characteristic of muscle tissue that sets apart from all other tissue types.

Contractility

What would occur if a muscle became totally depleted of ATP?

Death of muscle cells and rigor mortis.

Which of the following allows recoil of the muscle fiber when contraction ends?

Elastic filament (titin)

Match the functional characteristic of muscle with the appropriate descriptive term: Ability of a muscle to resume its resting length after being stretched.

Elasticity

The layer of dense irregular connective tissue that surrounds the entire skeletal muscle is the ___________. (hint:Please reduce this tissue on my New York Steak)

Epimysium

Skeletal muscle is responsible for overall body mobility. It can contract rapidly, but it tires easily and must rest after short periods of activity. Nevertheless, it can exert very little power.

False

Match the description to the event in the generation and propagation of an action potential: Propagation of the action potential.

Increased positive charge inside the sarcolemma changes permeability of adjacent areas, opening voltage-regulated Na+channels

Which of the following is not a characteristic of skeletal muscle?

It can contract for long periods of time without tiring.

Match the chemical to its description: Product of anaerobic glycolysis.

Lactic Acid

Select the correct description of ion movement at the neuromuscular junction that produces the end plate potential.

More sodium enters the muscle fiber than potassium leaves the muscle fibers

Which of the following is a special adaption present in skeletal muscle cells, but absent in most other cells?

Muscle cells have myoglobin: most other cells do not

Which of the following is an autoimmune disease that destroys acetylcholine receptors?

Myasthenia gravis

Match the following muscle chemical with the correct name: Oxygen storage molecule in skeletal muscle.

Myoglobin

In the sliding filament model of muscle contraction, the myofilaments slide over each other, resulting in the overlapping of actin and _______.

Myosin

Graded muscle contractions are smooth and varying in strength as different needs are placed on them. How can muscle contractions be graded?

Recruitment only

Match the following cellular component of a skeletal muscle fiber with it's description: Cytoplasm of a skeletal muscle fiber.

Sacroplasm

Match the following cellular component of a skeletal muscle fiber with its description: Plasma membrane of skeletal muscle fiber

Sarcolemma

Match the following description with the appropriate type of muscle: Subject to conscious control.

Skeletal muscle

Match the following description with the correct type of muscle: Striated and voluntary

Skeletal muscle

Which of the following muscle types is both voluntary and striated?

Skeletal muscle only

Match the following description to the appropriate type of muscle: Not subject to voluntary control, is nonstriated, and contractions are slow and sustained.

Smooth muscle

Match the following description to the muscle type: Visceral, one nucleus per cell, and non striated.

Smooth muscle

Match the following description with the correct type of muscle: Nonstriated. involuntary, found in the walls of hollow visceral organs.

Smooth muscle

Select the correct description of the voltage- gated ion channels for a region of sarcolemma that is undergoing repolarization.

Sodium channels close and potassium channels open

Match the following skeletal muscle structure with the correct description: Epimysium

Surrounds an entire muscle

Match the following skeletal muscle structure with the correct description: Perimysium

Surrounds each muscle bundle ( fascicle )

The energy required for muscle contraction is not 100% efficient (i.e., used). What happens to the energy that is not used for muscle contraction(s)?

The energy that is not used for muscle contraction(s) is lost because of the 1st law of Thermodynamics

Which of the following muscles is voluntary?

The muscle that extends the arm at the elbow