Exam 7: The Muscular System

Aerobic exercises do not increase skeletal muscle size, but they do cause various changes in the body. Explain what changes aerobic exercises initiate.

How do calcium ions affect muscle contractions?

Which of these junctions represents the connection between the tip of a neuron and a skeletal muscle cell from which acetylcholine diffuses?

A(n) ________ is the attachment point of a muscle to a bone that remains stationary during movement.

The myofibrils contain two protein filaments that contract the muscle. Of these, the ________ are the thinner filaments.

________ is a sustained, powerful contraction of a muscle that results from frequent stimulation with no time between stimuli for relaxation.

Why must tropomyosin cover the thin filament in just the right position before the muscle can relax?

The type of exercise that creates new blood vessels and makes the heart pump more efficiently is ________.

Your skeletal muscles might make a lot of these fast contractions when you are cold:________.

What causes delayed onset muscle soreness?

A bundle of muscle cells is called a(n) ________.

Which of these cell types can be described as muscle cells that contract rapidly, are rich in glycogen deposits, and depend on anaerobic respiration to produce ATP?

All muscles share four traits. All are excitable, contractile, extensible, and ________.

A(n) ________ consists of a motor neuron and all the muscle cells that it stimulates.

The muscle that extends and rotates the thigh when walking is called the ________.

The ________ is a modified form of endoplasmic reticulum that stores and releases calcium ions when a muscle contracts.

Why is ATP needed for muscle contraction?

George liked to go for very long runs; we can assume that this chemical becomes depleted during those marathons: ________.

Rigor mortis sets in after the death of humans and other animals because the supply of ATP decreases to the point at which calcium can no longer be removed from the cell. At this point, the myosin molecules attach to the thin filament. The muscles stiffen, and limbs cannot be moved. Why and for how long does the muscle then remain in this continuously contracted state?

A band of connective tissue that aids in the attachment of muscle to bone is a(n) ________.