Biology 2015

Isotopes differ in their
a. number of protons.
b. atomic number.
c. number of neutrons.
d. number of electrons

When an atom gains electrons, it
a. forms a negatively charged ion.
b. forms a positively charged ion.
c. forms covalent bonds.
d. forms ionic bonds.
e. gains atomic mass

An unequal sharing of electrons is a characteristic of a/an
a. ionic bond.
b. polar covalent bond.
c. nonpolar covalent bond.
d. All of these are correct

Hydrogen bonds are formed as a result of which of the following?
a. ionic bonds
b. nonpolar covalent bonds
c. polar covalent bonds
d. None of these are correct

Which of these properties of water can be attributed to hydrogen bonding between water molecules?
a. Water stabilizes temperature inside and outside the cell.
b. Water molecules are cohesive.
c. Water is a solvent for many molecules.
d. Ice floats on liquid water.
e. All of the above are correct.

match the statements with a property of water in the key.
KEY:
a. Water flows because it is cohesive.
b. Water holds its heat.
c. Water has neutral pH.
d. Water has a high heat of vaporization.

Sweating helps cool us off.

Match the statements with a property of water in the key.
KEY:
a. Water flows because it is cohesive.
b. Water holds its heat.
c. Water has neutral pH.
d. Water has a high heat of vaporization.

Our blood is composed mostly of water and cells

Match the statements with a property of water in the key.
KEY:
a. Water flows because it is cohesive.
b. Water holds its heat.
c. Water has neutral pH.
d. Water has a high heat of vaporization.

Our blood is just about pH 7.

Match the statements with a property of water in the key.
KEY:
a. Water flows because it is cohesive.
b. Water holds its heat.
c. Water has neutral pH.
d. Water has a high heat of vaporization.

We usually maintain a normal body temperature.

$H_{2} CO_{3} / NaHCO_{3}$ is a buffer system in the body. What effect the addition of an acid have on the ph of a solution that is buffered?

a. The pH will rise.
b. The pH will lower.
c. The pH will not change.
d. All of these are correct.

Which of these best describes the changes that occur when a solution goes from pH 5 to pH 7?

a. The solution is now 100 times more acidic.
b. The solution is now 100 times more basic.
c. The hydrogen ion concentration decreases by only a factor of 20, as the solution goes from basic to acidic.
d. The hydrogen ion concentration changes by only a factor of 20, as the solution goes from acidic to basic.