Lemon juice, which contains citric acid, is traditionally recommended for removing the odor associated with cleaning fish. What functional group is responsible for a “fishy” odor, and why does lemon juice work to remove the odor?

Find the boiling point of an aqueous solution containing a nonelectrolyte that freezes at

$$- 6.51 ^ { \circ } \mathrm { C }$$

.

Discuss the roles and adaptations of the cardiovascular and respiratory systems during exercise and training and identify the major changes that occur in skeletal muscles and the cardiorespiratory system in response to aerobic training.

List and describe several types of training used to improve cardiovascular fitness.

Hexylamine and triethylamine have the same molar mass. The boiling point of hexylamine is $129^{\circ} \mathrm{C}$, whereas that of triethylamine is only $89^{\circ} \mathrm{C}$. Explain these observations.

Name at least two undesirable characteristics are often associated with alkaloids.

How do amines differ from analogous alcohols in (a) odor, (b) basicity, and (c) boiling point?

What muscles protect the abdominal viscera?

What is the depression in the scapula that articulates with the humerus acromion?

Circle the BEST answer.
A contracture is
a The loss of muscle strength from inactivity
b A decrease in the size of a muscle
c A blood clot in the muscle
d The lack of joint mobility from shortening of a muscle

Draw the structure of the tetramethylammonium ion. Why does this species have a permanent positive charge?

PABA is used by certain bacteria as a starting material from which folic acid is made. Sulfa drugs such as sodium sulfanilamide work because they resemble PABA. The bacteria try to metabolize the sulfa drug, fail to do so, and die due to lack of folic acid. (a) Describe how this structure is similar to that of PABA. (b) Why do you think the sodium salt, rather than the neutral compound, is used as the drug?

para-Aminobenzoic acid (PABA) is a common ingredient in sunscreens. Draw the structure of PABA.

water-soluble vitamins differ from fat-soluble vitamins in that water-soluble vitamins are