Chapter 2 Quiz Questions

Question 1

Describe hydrogen bonds, and give two examples of their importance in cells.
Answer text Question 1

Answer 1

Hydrogen bond: When a weakly charged H+ ion (already attracted to electronegative molecule) is attracted to another electronegative atom of another molecule.

Give proteins and enzymes 3D shapes.

Bind enzymes to substrates.

Question 2

Discuss enzyme function.

Answer 2

Enzyme: A catalyst composed of a protein or RNA.

Main function is to increase rate of chem rxn by helping reactants overcome threshold energy required to break bonds into reactants.

Question 3

What are monosaccharides? Give 3 examples

GFD

Answer 3

They are simple sugars made up of carbon, hydrogen, and oxygen.

1. Glucose
2. Fructose
3. Deoxyribose

Question 4

Describe DNA Structure.

Answer 4

It’s a large molecule consisting of 2 helically wound chains of nucleotides. Base pairs are AT and GC

Question 5

What are 3 important lipid types and what do they do?

TPS

Answer 5

1. Triglycerides - Energy Storage
2. Phospholipids - Membrane Structure
3. Steroids - Hormone membrane structure

Question 6

What is a radioactive isotope?

Answer 6

A form of an isotope that is unstable and emits radiation as it breaks down.

Question 7

Define pH

Answer 7

A measure of hydrogen ion concentration of a solution.

Question 8

What 4 elements make up about 96% of our body weight?

Answer 8

Carbon
Hydrogen
Oxygen
Nitrogen

Question 9

Define base

Answer 9

A substance that dissociates into OH- ions and one or more cations.

Can also be described as having capacity to pick up one or more H+ ions.

Question 10

Define Acid

Answer 10

A substance that dissociates into hydrogen ions or one or more anions.

Question 11

How is ATP the energy currency of the cell?

Answer 11

ATP releases energy stored in its two high-energy phosphate bonds.

Question 12

What is a covalent bond?

Answer 12

A bond where molecules share electrons in a mutually stabilizing relationship.
Ex: Cl2

Question 13

What is an isotope?

Answer 13

A different form of an element, which is distinguishable due to the number of neutrons it carries.

Question 14

Define Lipid

Answer 14

A substance that is insoluble in water but soluble in non-polar solvents.

Question 15

What are Nucleotides?

Answer 15

Building blocks of nucleic acids. They are made up of a nitrogen base, a pentose sugar, and one or more phosphate groups.

Question 16

What is a buffer?

Answer 16

A combination of chemicals that minimizes changes in the pH of a solution when acids or bases are added.

Question 17

List 4 useful functions of H2O.

Answer 17

1. Good solvent
2. Participates in chem rxns vital to cell.
3. Absorbs heat without significantly changing its temperature much.
4. Acts as a lubricant.

Question 18

What are the 4 chem groups of an AA?

HACR

Answer 18

Hydrogen, Amine, Carboxyl, Side chain (R group)

Question 19

Define Ionic Bond

Answer 19

A bond in which ions of opposite charges are closely associating with each other.

Question 20

Define a salt

Answer 20

A substance that dissociates into cations and anions when put into water.
Ex: NaCl.

Question 21

What is an electrolyte?

Answer 21

A substance that breaks up ions when dissolved in water or body fluids.

Question 22

The most plentiful lipid in the human body is:

Answer 22

Triglyceride

Question 23

Which of the following is not a trace element?
a. Chromium
b. Copper
c. Fluorine
d. Phosphorus
e. Tin

Answer 23

d) Phosphorous