Cellular Respiration: Harvesting Chemical Energy

Question 1

The breakdown of organic molecules is

Answer 1

exergonic

Question 2

is a partial degradation of
sugars that occurs without O2

Answer 2

Fermentation

Question 3

consumes organic
molecules and O2 and yields ATP

Answer 3

Aerobic respiration

Question 4

is similar to aerobic
respiration but consumes compounds other
than O2

Answer 4

Anaerobic respiration

Question 5

includes both aerobic and
anaerobic respiration but is often used to refer
to aerobic respiration

Answer 5

Cellular respiration

Question 6

Cellular respiration equation with sugar glucose:

Answer 6

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy(ATP + heat)

Question 7

NADH passes the electrons to the

Answer 7

electron transport chain

Question 8

What pulls electrons down the chain in an energy-yielding tumble

Answer 8

O2

Question 9

Cellular respiration has three stages:

Answer 9

Glycolysis, Citric acid cycle, Oxidative phosphorylation

Question 10

(breaks down glucose into two
molecules of pyruvate)

Answer 10

Glycolysis

Question 11

(completes the
breakdown of glucose)

Answer 11

citric acid cycle

Question 12

(accounts for
most of the ATP synthesis)

Answer 12

Oxidative phosphorylation

Question 13

The process that generates most of the ATP is
called

Answer 13

oxidative phosphorylation because it is powered by redox reactions

Question 14

Oxidative phosphorylation accounts for almost _____ of the ATP generated by cellular
respiration

Answer 14

90%

Question 15

A smaller amount of ATP is formed in
glycolysis and the citric acid cycle by

Answer 15

substrate-level phosphorylation

Question 16

Glycolysis occurs in the cytoplasm and has two
major phases:

Answer 16

Energy investment phase
Energy payoff phase

Question 17

In the presence of O2, pyruvate enters the

Answer 17

mitochondrion

Question 18

Before the citric acid cycle can begin, pyruvate
must be converted to __________________ which links
the cycle to glycolysis

Answer 18

acetly CoA

Question 19

takes place within the mitochondrial
matrix

Answer 19

The citric acid cycle (Krebs Cycle)

Question 20

The Krebs Cycle produces:

Answer 20

1 ATP, 3 NADH, and 1 FADH2(flavin adenine dinucleotide)

Question 21

The acetyl group of acetyl CoA joins the cycle
by combining with

Answer 21

oxaloacetate, forming citrate

Question 22

The NADH and FADH2 produced by the cycle
relay electrons extracted from food to the

Answer 22

electron transport chain

Question 23

NADH and FADH2 donate electrons to
the electron transport chain, which powers

Answer 23

ATP Synthesis vio oxidative phosphorylation

Question 24

The electron transport chain is in the

Answer 24

cistae of the mitochondrion

Question 25

Most of the electron transport chain's components are

Answer 25

proteins, which exist in multiprotein complexes

Question 26

The carriers alternate __________________________________________________________ states as they accept and donate electrons

Answer 26

reduced and oxidized

Question 27

Electrons are passed through a number of proteins including _____________ to O2

Answer 27

cytochromes (each with an iron atom)

Question 28

The electron transport chain generates ______

Answer 28

no ATP

Question 29

The electron transport chain’s function is to

Answer 29

break the large free-energy drop from food to O2 into smaller steps the release energy in manageable amounts

Question 30

Electron transfer in the electron transport chain causes proteins to

Answer 30

pump H+ from the mitochondrial matrix to the intermembrane space

Question 31

H+ then moves back across the membrane, passing through channels in

Answer 31

ATP synthase

Question 32

ATP synthase uses the exergonic flow of H+ to

Answer 32

drive phosphorylation of ATP

Question 33

the use of energy in a H+ gradient to drive cellular work

Answer 33

chemiosmosis

Question 34

The energy stored in a ______________________ across a membrane couples the redox reactions of the electron transport chain to ATP synthesis

Answer 34

H+ gradient

Question 35

The H+ gradient is referred to as a ___________________, emphasizing its capacity to do work

Answer 35

proton-motive force

Question 36

During cellular respiration, most energy flows in this sequence:

Answer 36

glucose to NADH into electron transport chain into proton-motive force into ATP

Question 37

About _____ of the energy in a glucose molecule is transferred to ATP during cellular respiration,

Answer 37

40%

Question 38

Cellular respiration summary:

Answer 38

Glucose and Oxygen converted into Carbon dioxide, Water, and 36 or 38 ATP molecules.

Question 39

Fermentation uses _______________ instead of an electron transport chain to generate ATP

Answer 39

phosphorylation

Question 40

Types of fermentation:

Answer 40

alcohol fermentation lactic acid fermentation

Question 41

pyruvate is converted to ethanol in two steps, with the first releasing CO2 is used in brewing, winemaking, and baking

Answer 41

Alcohol fermentation

Question 42

pyruvate is reduced to NADH, forming lactate as an end product, with no release of CO2 is used to make cheese and yogurt

Answer 42

lactic acid fermentation

Question 43

carry out fermentation or anaerobic respiration and cannot survive in the presence of O2

Answer 43

Obligate anaerobes

Question 44

Yeast and many bacteria are _____________________________, meaning that they can survive using either fermentation or cellular respiration

Answer 44

facultative anaerobes