pal part 3 set for chapter 10

True With a steady amount of glucose and oxygen available, mitochondria can continue to produce the ATP needed for muscle contraction. The result is a prolonged period of activity. Anaerobic activities are usually brief because of a dependence on existing levels of ATP and CP, the amount of glycogen available, and the ability to withstand lactic acid buildup. Thus, periods of activity before the onset of fatigue are short.

Aerobic endurance is determined by the amount of glucose and oxygen available to fuel mitochondrial activity, while anaerobic endurance is determined by the amounts of ATP and CP already available. True False

sarcomere

An individual contractile unit within a myofibril in a muscle fiber is called a(n

True Although the muscle may bulge, it does not shorten.

In isometric contraction, the muscle does NOT change in length. True False

endurance

Muscle performance is considered in terms of power, the maximum amount of tension that can be produced by a muscle or muscle group, and , the amount of time an individual can perform an activity.

hypertrophy

Regular, repetitive, exhaustive stimulation of muscles leads to an increase in the number of mitochondria in those muscles. As a result, the muscles can be said to experience muscle

False Myosin and actin fibers are arranged similarly in skeletal and cardiac muscles; however, in smooth muscle the arrangement of myosin is scattered and actin fibers are loosely linked and incorporate the use of dense bodies.

The arrangement of myosin and actin fibers in skeletal, cardiac, and smooth muscles is identical. True False

True Calcium ions in the sarcoplasm bind to troponin, causing the active sites of actin to be exposed. After this, the SR immediately begins to uptake calcium ions from the sarcoplasm, triggering the release of calcium from troponin and the relaxation of the muscle cell.

The duration of muscle contraction and the following relaxation are affected by levels of calcium ions in the sarcoplasm. True False

False Troponin and tropomyosin, along with actin, compose the thin filaments.

Thick filaments are composed of myosin, troponin, and tropomyosin. True False

creatine phosphate phosphorylcreatine

When a muscle fiber has produced more ATP than it currently needs, the energy is transferred to form another high-energy compound called

isometric

While you sit at the computer reading this question, the postural muscles in your back are involved in contractions that produce tension but do not shorten muscle length. These are called contractions.

Acetylcholinesterase AChE

is the enzyme in the synaptic cleft that breaks down the neurotransmitter that starts a muscle contraction.

Z lines

During a sarcomere contraction, the A band length does not change, while the move closer together.

endomysium

The layer of connective tissue that surrounds an individual muscle fiber is called the