Chapter 4

Question 1

Cell respiration

Answer 1

oxidative reactions where cells gradually release energy from glucose,make it ATP

Question 2

Energy stored in ATP is

Answer 2

Immediately available for cellular activities such as contracting muscles, passing an impulse , etc.

Question 3

Equation for complete aerobic respiration of 1 molecule of glucose

Answer 3

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy

Question 4

Glucose combines with oxygen to produce

Answer 4

Energy (ATP) plus the waste products CO2 and water

Question 5

ATP is a

Answer 5

A special high-energy molecule that stores energy for immediate use in the cell

Question 6

ATP consists of

Answer 6

Adenosine (nucleotide adenine + ribose) + 3 phosphates

Question 7

The removal of 1 phosphate group from

Answer 7

ATP results in the formation of more stable and lower energy molecule, ADP

Question 8

Energy is absorbed to add a

Answer 8

Phosphate to ADP to produce ATP

Question 9

Mitochondrion is enclosed by 2 membranes

Answer 9

An outer membrane and an inner folded cristae membrane

Question 10

Inner membrane divides the mitochondria into

Answer 10

2 internal compartments, the outer compartment and matrix

Question 11

Krebs cycle takes place in the

Answer 11

matrix

Question 12

The electron transport chain takes place in the

Answer 12

Cristae membrane

Question 13

Cell respiration has 2 phases

Answer 13

Anaerobic and aerobic

Question 14

If oxygen is not present (anaerobic)

Answer 14

Glycolysis is followed by alcohol fermentation or lactic acid fermentation

Question 15

If oxygen is present (aerobic)

Answer 15

Glycolysis is followed by the Krebs cycle, the ETC, and chemiosmosis

Question 16

Anaerobic respiration (fermentation) originated

Answer 16

Billions of years ago when there was no free oxygen in Earth’s atmosphere

Question 17

The 2 types of fermentation

Answer 17

Alcohol fermentation and lactic acid fermentation

Question 18

Glycolysis produces

Answer 18

Pyruvic acid and a small amount of ATP

Question 19

Glycolysis

Answer 19

The anaerobic phase of aerobic respiration

Question 20

1 molecule of glucose breaks apart into

Answer 20

2 molecules of pyruvate

Question 21

What is pyruvate (or pyruvic acid)?

Answer 21

1/2 a glucose molecule

-is the raw material for the next step in respiration, the Krebs cycle

Question 22

Where does glycolysis occur?

Answer 22

cytoplasm

Question 23

Each step of glycolysis is controlled by

Answer 23

a different enzyme

Question 24

2 molecules of ATP supply the

Answer 24

energy of activation in glycolysis

Question 25

The energy of activation is the

Answer 25

energy needed to begin the reaction

Question 26

Glycolysis releases

Answer 26

4 ATP molecules, resulting in a net gain of 2 ATP

Question 27

glycolysis -1 glucose + 2 ATP --->

Answer 27

2 pyruvate + 4 ATP + 2 NADH (net gain 2 ATP)

Question 28

alcohol fermentation

Answer 28

certain cells convert pyruvic acid/pyruvate from glycolysis into ethyl alcohol and CO2 in the absence of oxygen

Question 29

The bread baking industry depends on the

Answer 29

ability of yeast to carry out fermentation and produce the CO2 that causes bread to rise

Question 30

The beer, wine, and liquor industries depend on

Answer 30

yeast to ferment sugar into ethyl alcohol

Question 31

Lactic acid fermentation

Answer 31

occurs during strenuous exercise when the body cannot keep up with the increased demand for oxygen by skeletal muscles

Question 32

What causes fatigue and burning in one's muscles?

Answer 32

pyruvic acid produced by glycolysis that converts to lactic acid that builds up in muscles

Question 33

What does the phrase "no pain, no gain" refer to?

Answer 33

pain caused by lactic acid buildup in skeletal muscles

Question 34

When an increase in blood flow restores proper oxygen levels

Answer 34

the muscle tissue reverts to the more efficient aerobic respiration and lactic acid is removed from the muscles

Question 35

Where is lactic acid carried?

Answer 35

the liver where it is converted back to pyruvic acid

Question 36

Aerobic respiration consists of 3 processes:

Answer 36

glycolysis, the Krebs cycle, and the electron transport chain

Question 37

The krebs cycle is also known as

Answer 37

the citric acid cycle

Question 38

The krebs cycle is the

Answer 38

first stage of the aerobic phase of cellular respiration

Question 39

Pyruvic acid (from glycolysis) combines with coenzyme A (a vitamin derivative)

Answer 39

to form Acetyl-CoA , which enters the Krebs cycle

Question 40

Each turn of the Krebs cycle produces 1 molecule of

Answer 40

both ATP and FADH2 plus 3 molecules of NADH

Question 41

What is the by-product of the Krebs cycle?

Answer 41

CO2 (which is exhaled)

Question 42

In summary, the Krebs cycle produces

Answer 42

- a small amount of ATP - carbon dioxide - NADH and FADH2

Question 43

What are NADH and FADH2 molecules?

Answer 43

coenzymes that shuttle protons and electrons from glycolysis and the Krebs cycle to the ETC

Question 44

NAD+ is | NADH is

Answer 44

oxidized form | reduce form

Question 45

FAD+ is | FADH2 is

Answer 45

oxidized form | reduced form

Question 46

NAD and FAD carry

Answer 46

H+ (protons) from the Krebs cycle to the ETC

Question 47

Each ETC consists of a

Answer 47

series of carrier proteins that transport high energy electrons from the Krebs cycle

Question 48

The energy from these high energy electrons is coupled with/powers the

Answer 48

pumping of protons across the cristae membrane in the outer compartment in order to create a proton gradient

Question 49

The potential energy in this proton gradient is then used to

Answer 49

produce ATP through a process called chemiosmosis

Question 50

Chemiosmosis is also called

Answer 50

oxidative phosphorylation

Question 51

Almost all the ATP produced during aerobic cell respiration is

Answer 51

produced by chemiosmosis

Question 52

The ETC produces

Answer 52

a proton gradient

Question 53

The gradient represents

Answer 53

stored or potential energy that can be used to do work

Question 54

chemiosmosis uses the stored energy in the proton gradient to

Answer 54

convert ADP into ATP

Question 55

Chemiosmosis uses the energy stored in the proton gradient to

Answer 55

power the synthesis of ATP

Question 56

What does chemiosmosis depend on?

Answer 56

a very special molecule located within the cristae membrane called ATP synthetase

Question 57

What is ATP synthetase?

Answer 57

a proton channel structure that can spin like a turbine

Question 58

What happens as protons pour through the ATP synthetase channel?

Answer 58

part of the molecule turns and attaches phosphates to ADP molecules, forming molecules of ATP

Question 59

oxygen has a strong attraction for

Answer 59

electrons and protons

Question 60

What is oxygen's role in the chemiosmosis?

Answer 60

- it pulls the electrons through the ETC | - serves as the final electron/proton acceptor in the ETC

Question 61

When oxygen combines with protons and electrons at the end of the ETC

Answer 61

water is formed as a waste product, this is the water vapor we constantly exhale

Question 62

Every mitochondrian contains

Answer 62

1000s of ETCs

Question 63

The ETC carries electrons through a series of

Answer 63

redox reactions as special molecules bind to and let go of electrons

Question 64

Protons cannot diffuse directly through the cristae membrane but can only cross through

Answer 64

ATP synthetase channels

Question 65

During respiration, most energy flows in this sequence

Answer 65

glucose --> NAD and FAD --> ETC (chemiosmosis) --> ATP