Chapter 6

Question 1

Sun - Heat - Producers - Consumers - Decomposers - Heat

Answer 1

Flow of Energy

Question 2

the capacity to do work

Answer 2

energy

Question 3

the energy of motion

Answer 3

kinetic energy

Question 4

stored energy

Answer 4

potential energy

Question 5

Most forms of energy can be converted into … that is measured in …

Answer 5

heat energy, calories

Question 6

Potential energy is stored in chemical bonds that can be transferred from 1 molecule to another through …

Answer 6

electron transfer (oxidation and reduction)

Question 7

1st Law of Thermodynamics

Answer 7

energy can’t be created or destroyed, only converted to different forms

Question 8

2nd Law of Thermodynamics

Answer 8

without external energy input, all systems naturally become more disorderly overtime

Question 9

measure of disorder (S)

Answer 9

entropy

Question 10

energy available to do work (G, Gibb’s … energy)

Answer 10

free energy

Question 11

energy contained in molecules’ chemical bonds (H)

Answer 11

enthalpy

Question 12

free energy equation

Answer 12

ΔG = ΔH - (T x ΔS)

Question 13

if product contains more free energy than reactants, ΔG is …

Answer 13

positive

Question 14

if product contains less free energy than reactants, ΔG is …

Answer 14

negative

Question 15

endergonic reaction

Answer 15

require free energy (+ΔG), anabolic, building big things from small things

Question 16

exergonic reaction

Answer 16

releases free energy (-ΔG), catabolic, breaking big things into small things

Question 17

activation energy

Answer 17

energy needed to get a reaction started by destabilizing chemical bonds

Question 18

catalyst

Answer 18

substances that lower the activation energy of a reaction

Question 19

ATP

Answer 19

energy currency of cell

Question 20

ATP structure

Answer 20

• ribose (5 C sugar)
• adenine (nucleotide)
• 3 phosphates

Question 21

ATP energy is stored in …

Answer 21

phosphate bonds

Question 22

when P bonds are broken …

Answer 22

energy is released (exergonic)

Question 23

when P are kept bonded by …

Answer 23

energy is absorbed (endergonic)

Question 24

ATP becomes … and … when energy is released and when H2O is added

Answer 24

ADP and Pi

Question 25

- catalyze biological reactions - nearly all are proteins - lowers the activation energy - temporary ...-substrate complexes are formed during reactions

Answer 25

enzymes

Question 26

molecules that will undergo a reaction (reactants)

Answer 26

substrate

Question 27

region of the enzyme that binds to the substrate

Answer 27

active site

Question 28

enzymes don't automatically fit with substrates so ...

Answer 28

enzymes will change shapes when substrate gets near active site to fit the substrate

Question 29

ribozymes

Answer 29

RNA with enzymatic abilities

Question 30

enzyme function is affected by ...

Answer 30

its environment: - pH - temperature - concentration of reactants and products - regulatory molecules (co-enzymes and co-factors)

Question 31

temperature effect on enzyme function

Answer 31

enzyme activity will increase with temperature until it goes over the temp optimum, causing denaturing

Question 32

pH effect on enzyme function

Answer 32

enzyme will denature if out of optimum pH

Question 33

inhibitors

Answer 33

molecules that bind to enzymes to decrease their activity

Question 34

competitive inhibitors

Answer 34

competes with substrate for binding to active site

Question 35

noncompetitive inhibitors

Answer 35

bind to sites other than the active site (allosteric inhibitor)

Question 36

allosteric enzymes

Answer 36

exist in either active or inactive states and possess an allosteric site that molecules other than substrate bind to

Question 37

allosteric inhibitors

Answer 37

binds to allosteric site to inactivate the enzyme

Question 38

allosteric activators

Answer 38

binds to allosteric site to activate the enzyme

Question 39

metabolism

Answer 39

all chemical reactions occurring in an organism

Question 40

anabolic

Answer 40

endergonic reactions that use energy to make chemical bonds

Question 41

catabolic

Answer 41

exergonic reactions that release energy when bonds are broken

Question 42

some enzymes require ... for proper activity

Answer 42

additional molecules

Question 43

co-factors

Answer 43

usually, metal ions found in active site

Question 44

co-enzymes

Answer 44

organic molecules often used to donate or accept electrons in the redox reaction

Question 45

biochemical pathways

Answer 45

series of reactions in which the product of one reaction is used at the substrate for the next reaction

Question 46

multienzyme complexes in membranes

Answer 46

1. The product of one reaction is directly delivered to the next enzyme. 2. Unwanted side reactions are reduced. 3. Reactions can be regulated as a unit.

Question 47

feedback inhibition

Answer 47

the end product of a biochemical pathway is an allosteric inhibitor of an earlier enzyme in the pathway