Bioenergetics

Question 1

study of energy transfer within living things

Answer 1

bioenergetics

Question 2

3 reasons for studying bioenergetics

Answer 2

1. the role of energy is fundamental to biological processes like growth, development and metabolism
2. the ability to harness energy from a variety of metabolic pathways is a property of all living organisms
3. life is dependent on energy transformations. living organisms survive because of exchange of energy within and without

Question 3

2 laws of bioenergetics

Answer 3

1. energy cannot be created nor destroyed, but can be change from one form to another
2. energy transfer will always proceed in the direction of increased entropy, and the release of free energy

Question 4

light → chemical → electrical

Answer 4

sight

Question 5

chemical → mechanical

Answer 5

muscle contraction

Question 6

chemical → electrical

Answer 6

action potentials

Question 7

light → chemical

Answer 7

vitamin D

Question 8

water → water vapor

Answer 8

sweating (change of state)

Question 9

4 examples of energy transfer within the human body or other biological systems

Answer 9

1. eye sight
2. muscle contraction
3. vitamin D formation
4. photosynthesis

Question 10

light energy → chemical energy in plants

Answer 10

photosynthesis

Question 11

(3 lessons from the first law of thermodynamics)

the main forms of energy within the body are:

Answer 11

• heat
• light chemical
• mechanical entropy
• “free energy”

Question 12

(3 lessons from the first law of thermodynamics)

a form of energy that cannot be reused in chemical reactions and is synonymous to increased randomness or disorder

Answer 12

entropy

Question 13

(3 lessons from the first law of thermodynamics)

referred to as G or Gibb’s free energy;

Answer 13

“free energy”

Question 14

(7 lessons from the 2nd law of thermodynamics)

all reactions proceed in the direction of:

Answer 14

a. entropy
b. a release of free energy (Kcal/Mol)

Question 15

(7 lessons from the 2nd law of thermodynamics)

the more ___ the change in Gibb’s free energy, the ____ the release of free energy during a chemical reaction

Answer 15

1. negative
2. greater

Question 16

(7 lessons from the 2nd law of thermodynamics)

chemical reactions that have a negative change in Gibb’s free change are termed

Answer 16

exergonic reactions

Question 17

(7 lessons from the 2nd law of thermodynamics)

free energy not used to do work is expressed as _____

Answer 17

heat

Question 18

(7 lessons from the 2nd law of thermodynamics)

reactions that have no net change in substrate or product, and have no change in free energy, are termed _____

Answer 18

equilibrium reactions

Question 19

(7 lessons from the 2nd law of thermodynamics)

all reactions are potentially ____

Answer 19

reversible

Question 20

(7 lessons from the 2nd law of thermodynamics)

the amount of free energy release of a chemical reaction can be modified by _________

Answer 20

altering substrate and product concentrations

Question 21

atp is also called

Answer 21

adenosine triphosphate

Question 22

atp is composed of

Answer 22

anenine + ribose + phosphate group

Question 23

which phosphate group contains the most energy?

Answer 23

last phosphate group (PO4)

Question 24

process of breaking the bonds of atp;

occurs continually in cells;

ATPase can weaken and break last PO4 bond releasing energy and free PO4

Answer 24

phorphorylation

Question 25

3 roles of ATP in metabolism

Answer 25

1. used for active nutrient breakdown 2. used for physiological processes 3. used for biosynthetic reactions

Question 26

roles of ATP in metabolism

Answer 26

1. formed by substate-level phosphorylation 2. oxidative phosphorylation 3. photophosphorylation

Question 27

roles of ATP in metabolism

Answer 27

1. turnover 2. storage

Question 28

proteins that increase the rate of reaction by lowering the energy of activation; catalyze nearly all the chemical reactions taking place in the cells of the bodyl not altered or consumed during reaction; reusable

Answer 28

enzymes

Question 29

3 mechanisms by which enzymes accelerate reactions

Answer 29

1. maintain precise substrate orientation (lower entropy of substrates) 2. change substrate reactivity by altering its electrostatic structure 3. exert physical stress on bonds in the substrate to be broken (induced fit)

Question 30

3 types of enzyme specificity

Answer 30

1. absolute 2. group 3. linkage

Question 31

catalyze one type of reaction for a "single" substrate

Answer 31

absolute type of enzyme

Question 32

catalyze one type of reaction for "similar" substrates

Answer 32

group type of enzyme

Question 33

catalyze one type of reaction for a "specific" type of bond

Answer 33

linkage type of enzyme

Question 34

(determine which type of enzyme) urease catalyzes only the hydrolysis of urea

Answer 34

absolute type of enzyme

Question 35

(determine which type of enzyme) chymotrypsin catalyzes the hydrolysis of peptide bonds

Answer 35

Linkage

Question 36

(determine which type of enzyme) hexokinase adds a phosphate group to hexoses

Answer 36

group

Question 37

2 importance of enzymes

Answer 37

1. lower a reaction's activation energy 2. speed up reactions 3. precise, very specific yet flexible

Question 38

3 cellular respirations

Answer 38

1. glycolysis 2. citric acid cycle 3. electron transport chain

Question 39

(determine the step in glycolysis) begins with the phosphorylation of glucose into glucose 6-phosphate, using an ATP and a kinase enzyme

Answer 39

step 1

Question 40

(determine the step in glycolysis) the aldehyde end of the molecule is oxidized and phosphorylated by a dehydrogenase enzyme and NAD+; this produces 1,3-bisphospho-glycerate and NADH

Answer 40

step 6

Question 41

(determine the step in glycolysis) the phosphorylation of fructose 6-phosphate into fructose 1,6-biphosphate with a kinase enzyme

Answer 41

step 3

Question 42

(determine the step in glycolysis) the phosphate group is transferred onto an ADP with a kinase enzyme, forming 3-phosphoglycerate and ATP

Answer 42

step 7

Question 43

(determine the step in glycolysis) the phosphate group is "isomerized" to a new position in 2-phosphoglycerate

Answer 43

step 8

Question 44

(determine the step in glycolysis) "isomerizes" glucose 6-phosphate to fructose 6-phosphate with an "isomerase" enzyme

Answer 44

step 2

Question 45

(determine the step in glycolysis) "cleaves" the fructose ring into a dihydroxy-acetone phosphate and a glyceraldehyde 3-phosphate

Answer 45

step 4

Question 46

(determine the step in glycolysis) "water is lost" to form phosphoenol-pyruvate

Answer 46

step 9

Question 47

(determine the step in glycolysis) "isomerized the dihydroxyacetone phosphate into another glyceraldehyde 3-phosphate

Answer 47

step 5

Question 48

(determine the step in glycolysis) the "phosphate is transferred" to an ADP yielding "pyruvate" and "ATP" with a "kinase" enzyme

Answer 48

step 10

Question 49

glucose is converted to two molecules of pyruvate; an anaerobic reaction in cytoplasm

Answer 49

glycolysis

Question 50

total number of reactions in glycolysis

Answer 50

10

Question 51

(summary of glycolysis) what happens in steps 1-5?

Answer 51

energy investment phase

Question 52

(summary of glycolysis) what happens in steps 6-10

Answer 52

energy-generating phase

Question 53

(state what phase of glycolysis) 2 ATP molecules are hydrolyzed; the 6-carbon glucose molecules is converted into two 3-carbon segments

Answer 53

energy investment phase

Question 54

(state what phase of glycolysis) producing q NADH and 2 ATPs for each pyruvate formed

Answer 54

energy-generating phase

Question 55

how many ATPs are used in phase 1 of glycolysis?

Answer 55

2

Question 56

total number of ATPs made in phase 2 of glycolysis

Answer 56

4

Question 57

what is the net result of glycolysis?

Answer 57

synthesis of 2 ATPs from glycolysis

Question 58

these are made in the cytoplasm and must be transported to the mitochondria to join the electron transport chain and make ATP

Answer 58

2 NADH