Chp 21

Question 1

Which body structure is part of the axial skeleton?

Answer 1

skull

Question 2

which component of bone is responsible for producing blood cells?

Answer 2

marrow

Question 3

How do the hormones involved in blood calcium homeostasis actually function?

Answer 3

Both parathyroid hormone and calcitonin act to raise blood calcium levels.

Question 4

Why are women more proficient than men on the balance beam apparatus used in gymnastics?

Answer 4

Women have a lower center of gravity because their torsos are long relative to leg length.

Question 5

A pitcher throws a baseball by lowering the forearm to straighten the arm. During this movement, the biceps muscle ________ and the triceps muscle ________.

Answer 5

relaxes; contracts

Question 6

How does a sarcomere shorten using the sliding filament mechanism of muscle contraction?

Answer 6

As they slide past each other, actin filaments shorten, while myosin filaments do not shorten.

Question 7

Arm and leg muscles are arranged in antagonistic pairs. How does this affect their functioning?

Answer 7

It allows the muscles to produce opposing movements.