Question

Identify the letter of the choice that best completes the statement or answers the question.

1. Nonpolar molecules have

a. no negative or positive poles:

b. both negative and positive poles.

c. only a negative pole.

d. only a positive pole.

2. A molecule that has a partial positive charge on one side and a partial negative charge on the other side is called a

a. nonpolar molecule.

b. polar molecule,

c. charged molecule.

3. Water is important to life because it

b. is found inside cells.

c. influences the shape of the a membrane.

d. All of the above,

4. Which of the following characteristics of water is not a result of hydrogen bonding?

a. adhesive strength,

b. capillarity

c. cohesive strength

d. All of the above are a result of hydrogen bonding.

5. Which of the following is a carbohydrate?

a. DNA

c. Wax

b. insulin

d. sucrose

6. Polysaccharides are

a. carbohydrates.

c. proteins.

b. lipids.

d. unsaturated fats.

7. Long chains of amino acids are found in.

a. carbohydrates.

c. proteins.

b. Lipids.

d. sugars.

8. Refer to the illustration above. Molecules like Molecule B are found in

4. carbohydrates.

b. lipids.

c. nucleic acids.

d. proteins.

9. Lipids are

a. polar molecules.

b. similar to water molecules.

c. protein molecules.

d nonpolar molecules.

10. All of the following are examples of lipids except

Answer 1

Answer:

1). A. No negative or positive poles

Explanation:

Nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.

2). D. Bipolar molecule

Explanation:

This unequal sharing of the electrons in the O-H bond in water causes the hydrogens to have a partial positive charge (positive dipole), and the oxygen has a partial negative charge (negative dipole). Water is called a polar molecule because it has a positive side and a negative side, called a dipole moment.

3). D. All of the above

4). D. all of the above are a result of hydrogen bonding

5). D. Sucros

Explanation:

DNA is nucleic acid.

Wax is a lipid.

Insulin is a hormone(protein).

6). A. Carbohydrates

Explanation:

Poly = many, saccharine = sugar

7). C. Proteins

Explanation: Amino acids are arranged in linear sequence by peptide bonds called proteins.

8). A. Carbohydrate

9). D. Nonpolar molecule

Explanation:

A molecule that consists of two atoms of the same element – is nonpolar precisely because it is completely symmetric.