test 1: ch4

Question 1

what is a reversible reaction?

Answer 1

when a chemical reaction can proceed in either direction (indicated by a double arrow)

Question 2

true or false: if you increase the amount of reactants that you start with, then it will increase the amount of product that you end up with

Answer 2

true

Question 3

another name for enzymes

Answer 3

catalysts (because they increase the rate of the reaction

Question 4

_______ increase the rate of a reaction by lowering the activation energy of the reaction

Answer 4

enzymes

Question 5

what does denature mean?

Answer 5

to unfold and become inactive

Question 6

reactants in a chemical reaction influenced by enzymes and interact with enzymes much like a lock and key

Answer 6

substrates

Question 7

activity of enzymes depend on what?

Answer 7

the concentration of enzyme and substrates, the pH and temp of enzymes, and the concentrations of coenzymes and cofactors

Question 8

names that end in -____ are named for function

Answer 8

-ase

Question 9

derived from water-soluble vitamins and aid the enzyme

Answer 9

co-enzymes

Question 10

a type of co-enzyme derived from vitamin B3 (niacin) - transports one hydrogen atom between enzymes

Answer 10

NAD

Question 11

a type of co-enzyme derived from vitamin B2 (riboflavin) - transports two hydrogen atoms between enzymes

Answer 11

FAD

Question 12

aid the enzyme by eliciting a conformational change to help substrate bind; metal ions, such as Ca2+, Mg2+, Mn2+, Cu2+, Zn2+

Answer 12

cofactors

Question 13

energy cannot be created nor destroyed; only transformed

Answer 13

first law of thermodynamics

Question 14

energy transformations increase the entropy (disorganization of a system

Answer 14

second law of thermodynamics

Question 15

a reaction that requires an input of energy

Answer 15

endergonic reaction

Question 16

a reaction that gives off energy

Answer 16

exergonic reaction

Question 17

true or false: the amount of energy in a molecule is measured by calories

Answer 17

true

Question 18

calorie with a capital C is known as…

Answer 18

1000 calories

Question 19

calorie with a lowercase c is known as…

Answer 19

the amount of heat required to raise the temp. of 1cm3 of water 1⁰C

Question 20

in oxidation-reduction reactions, a substance is _________ if:

1. it loses electrons in the course of a reaction
2. it gains oxygen in the course of a reaction while losing hydrogen in the course of a reaction

Answer 20

oxidized

Question 21

LEO the lion says GER; LEO stands for…

Answer 21

loss of electrons = oxidation

Question 22

in oxidation-reduction reactions, a substance is _________ if:

1. it gains electrons in the course of a reaction
2. it loses oxygen in the course of a reaction while gaining hydrogen in the course of a reaction

Answer 22

reduced

Question 23

LEO the lion says GER; GER stands for…

Answer 23

gain of electrons = reduction

Question 24

true or false: oxidation-reduction reactions in the body are always coupled, so if a substance is oxidized then another has been reduced and vice versa

Answer 24

true

Question 25

in an oxidation-reduction reaction, the substance that is reduced is also called the ________ _______ because it caused another substance to be oxidized

Answer 25

oxidizing agent

Question 26

oxidizing agents can take hydrogen away from a substance causing it to be oxidized, examples are:

Answer 26

NAD+ and FAD

Question 27

reducing agents can donate hydrogen toa substance causing it to be reduced, examples are:

Answer 27

NADH and FADH2