Chemical Foundations of Life

Question 1

Define potential energy.

Answer 1

Energy that is inactivated or stored.

Question 2

Define kinetic energy.

Answer 2

Energy generated by motion.

Question 3

Define chemical energy.

Answer 3

Energy that is stored in chemical bonds and released when those bonds are broken.

Question 4

Define radiant energy.

Answer 4

Energy that travels in waves such as heat or light.

Question 5

Define electrical energy.

Answer 5

Energy from the movement of charged particles (ions/electrons).

Question 6

Where in the body is electrical energy utilized?

Answer 6

In muscles and nerves.

Question 7

What are the four main chemical components of the human body?

Answer 7

Carbon, Oxygen, Nitrogen, and Hydrogen.

Question 8

What is a radioisotope?

Answer 8

An unstable, heavy isotope that decomposes and releases radiation as it decomposes.

Question 9

Define half-life.

Answer 9

The time it takes for an isotope to lose half of its radioactivity.

Question 10

What is an ionic bond?

Answer 10

A bond between an electron donor and electron acceptor (ex. Na+ and Cl- make NaCl)

Question 11

What is a covalent bond?

Answer 11

A bond between two uncharged atoms who share electrons to fill their valence shells.

Question 12

What is a hydrogen bond?

Answer 12

A covalent bond between H and other atoms such as O and N.

Question 13

Name the types of chemical bonds from strongest to weakest.

Answer 13

Ionic, covalent, hydrogen.

Question 14

Which two factors affect the rate of chemical reactions?

Answer 14

The concentration of the reactants and the temperature.

Question 15

How do catalysts speed up chemical reactions?

Answer 15

They lower the activation energy to make it easier for the reaction to progress forwards.

Question 16

What are free radicals?

Answer 16

An electrically charge atom with an unpaired electron in the outer shell.

Question 17

What danger do free radicals pose?

Answer 17

They cause aging, cancer, diabetes, and emphysema.

Question 18

What are antioxidants?

Answer 18

Substances that inactivate free radicals.

Question 19

Define acid.

Answer 19

A substance that produces hydrogen ions upon dissociation; a proton donor.

Question 20

Define acid.

Answer 20

A substance that produces hydroxide ions; a proton acceptor.

Question 21

What is a salt?

Answer 21

A substance that dissociates to produce ions other than H+ or OH-

Question 22

What is sucrose made up of?

Answer 22

Glucose and fructose.

Question 23

What is lactose made up of?

Answer 23

Glucose and galactose.

Question 24

What is maltose made up of?

Answer 24

Two glucose molecules.

Question 25

What is the function of triglycerides?

Answer 25

To provide long-term energy storage.

Question 26

What are saturated fats?

Answer 26

Triglycerides that only contain single covalent bonds between carbons.

Question 27

What are unsaturated fats?

Answer 27

Triglycerides that contain one or more double bonds between carbons.

Question 28

What are essential fatty acids and name the three most important?

Answer 28

Essential fatty acids are not produced by the body and must be obtained from the diet. The most important are omega-3, omega-6, and cis-fatty acids.

Question 29

What are the benefits of omega-3 and -6 fatty acids?

Answer 29

Protect against heart disease, stroke, and arthritis, promote wound healing, improve some skin disorders, and improve mental function.

Question 30

How can you tell if a molecule is a steroid?

Answer 30

Its structure; it will have four rings of carbon.

Question 31

What are the sex hormones made from?

Answer 31

Steroids, which began as cholesterol.

Question 32

What are the six functions of proteins?

Answer 32

They act structurally, they have regulatory properties, they are contractile (like in muscle tissue), they can be immunological (as in antibodies), they can transport, and they can catalyze reactions.

Question 33

How is a peptide bond formed?

Answer 33

Through dehydration (removal of a water molecule from the two molecules to bind a Carbon atom and Nitrogen atom together.

Question 34

What conditions can cause denaturation?

Answer 34

Change in temperature, pH, or electrolyte concentration.

Question 35

What are the parts of a nucleic acid?

Answer 35

A phosphate, a pentose sugar, and a nitrogenous base.

Question 36

What is the difference between RNA and DNA

Answer 36

The ribose in DNA does not contain the extra oxygen molecule that RNA does.

Question 37

How does ATP generate energy?

Answer 37

A great amount of chemical energy is stored within the last phosphate bond of the phosphate group and releases this energy when the last phosphate is hydrolyzed.