Chapter 2

Question 1

Brownian Motion

Answer 1

Is the random movement of molecules in a fluid or gas powered by the background thermal energy.

Question 2

Water is said to be polar but uncharged, how is that possible?

Answer 2

Water is polar because the hydrogen has a partial positive charge, and oxygen has a partial negative charge and is electronegative, so, the total charge on the molecule is zero, that is, the positive charges are equal to the negative charges

Question 3

Why are weak bonds important in biochemistry?

Answer 3

Many weak bonds allow for highly specific yet transient interactions

Question 4

What are the common types of weak bonds important in biochemistry? How does water affect each of these bonds?

Answer 4

1. Ionic bonds
2. Hydrogen Bonds

Water disrupts ionic and hydrogen bonds

3. Van der walls interactions

Because Van der walls interactions interactions are common between hydrophobic groups, water strengthens these bonds by facilitating their formation through the hydrophobic effect

Question 5

In liquid water, each molecule is hydrogen bonded to a proximately 3.4 molecules of water. What affected freezing water have on the number of hydrogen bonds? Heating water?

Answer 5

Lowering the temperature would reduce the motion of the water molecules and allow the formation of more hydrogen bonds (ice is hydrogen bonded to 3.7 molecules of water)

Heating the water makes fewer hydrogen bonds form, (at 100°C, a molecule of water is hydrogen bonded to 3.2 water molecules).

Question 6

What would be the effect of an organic solvent on electrostatic interactions?

Answer 6

Electrostatic interactions will be stronger in organic solvents relative to polar solvents because there will be no competition from the solvent for the components of the electrostatic interaction.

Question 7

What is in electronegative atom and why are such atoms important in biochemistry?

Answer 7

And electronegative atom is one that has a high affinity for electrons. Consequently, when bonded to hydrogen atom, the electronegative atom assumes a partial negative charge and the hydrogen atom assumes a partial positive charge, such polarity allows the formation of hydrogen bonds.

Question 8

Define the hydrophobic Effect

Answer 8

The hydrophobic effect is the tendency of nonpolar molecules to interact with one another in the presence of water. This Interaction is powered by the increase in entropy of water molecules when the nonpolar molecules are removed from the watery environment.

Question 9

How does the second law of thermodynamics allow for the formation of biochemical order

Answer 9

The second law of thermodynamics states that the entropy of a system and its surroundings always increases in a spontaneous process. When hydrophobic molecules are sequestered away from water, the entropy of water increases. Search sequestration called the hydrophobic effect, also leads to the formation of biochemical structures.

Question 10

Electrostatic Interactions

Answer 10

A week interaction between ions having opposite charges, also called an ionic bond

Question 11

van der Walls interactions

Answer 11

The attraction between two molecules based on transient electron asymmetry around and atom that induces a complementary asymmetry in a nearby molecule

Question 12

pH

Answer 12

A measure of the hydrogen ion concentration of a solution

Question 13

Buffer

Answer 13

And acid – base conjugate pair that resists change in the pH of a solution