Chapter 9 - Cellular Respiration

Question 1

define cellular respiration

Answer 1

the catabolic pathways of aerobic and anaerobic respiration, which break down organic molecules and use an electron transport chain for the production of ATP; the oxidation of glucose and the capture of energy in a useful form

Question 2

what is the chemical reaction equation for photosynthesis?

Answer 2

6CO2 + 6H2O + light energy -> C6H12O6 + 6O2

Question 3

what is the chemical reaction equation for cellular respiration

Answer 3

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP energy + heat

Question 4

in what part of plant cells does photosynthesis occur?

Answer 4

chloroplasts

Question 5

where does cellular respiration occur?

Answer 5

the mitochondria

Question 6

what two mechanisms generate ATP?

Answer 6

substrate-level phosphorylation and oxidative phosphorylation

Question 7

define oxidative phosphorylation

Answer 7

energy is stored as a hydrogen ion gradient across a membrane, then used to make ATP

Question 8

define substrate-level phosphorylation

Answer 8

enzyme transfers phosphate group from organic substrate to ADP

Question 9

describe glycolysis

Answer 9

glucose -> pyruvate - (in the cytosol)

Question 10

describe breakdown of pyruvate

Answer 10

formation of acetyl-CoA (in matrix) and citric acid cycle (Krebs cycle) (in matrix) - (in mitochondrion)

Question 11

describe oxidative phosphorylation

Answer 11

1. electron transport chain (in inner membrane) 2. ATP synthesis (by chemiosmosis) - (in mitochondrion)

Question 12

describe fermentation

Answer 12

a. lactic acid fermentation b. alcohol fermentation - (in cytosol)

Question 13

list the processes involved in cellular respiration

Answer 13

redox reactions, chemiosmosis, phosphorylation

Question 14

what is glucose a rich source of and what withdraws it from glucose?

Answer 14

glucose is a rich source of electrons, NAD+ and dehydrogenase withdraw these electrons

Question 15

describe the electron transport chain

Answer 15

electrons cascade down series of electron carriers of the electron transport chain; in cellular respiration, cascading electrons release energy in small increments and finally reduce O2

Question 16

define glycolysis

Answer 16

harvesting chemical energy by oxidizing glucose to pyruvate; takes place in the cytosol; begins the oxidation of glucose; nets 2 ATP and 2 NADH

Question 17

what two phases can glycolysis be divided into?

Answer 17

the energy investment phase and the energy payoff phase

Question 18

is O2 needed in any of the glycolytic reactions?

Answer 18

no. no O2 is needed in any of the glycolytic reactions

Question 19

what is formation of Acetyl-CoA?

Answer 19

pyruvate is groomed for the citric acid cycle

Question 20

where does the Krebs cycle occur?

Answer 20

in the mitochondrial matrix

Question 21

what does the Krebs cycle do?

Answer 21

completes the oxidation of organic fuel

Question 22

what does the Krebs cycle produce?

Answer 22

ATP, NADH, FADH2, CO2

Question 23

what does the electron transport system do?

Answer 23

built into the inner mitochondrial membrane, electrons lose energy as they are passed along, energy is used to pump hydrogen ions against the gradient into the intermembrane space

Question 24

what donates electrons to the electron transport chain?

Answer 24

NADH and FADH2

Question 25

what is the most common control mechanism?

Answer 25

feedback inhibition

Question 26

when does fermentation occur?

Answer 26

after glycolysis when there is no oxygen available

Question 27

what is the purpose of fermentation?

Answer 27

an anaerobic alternative to aerobic respiration

Question 28

list examples of alcohol fermentation

Answer 28

by yeast in brewing, winemaking, and baking

Question 29

what fermentation do human muscle cells use?

Answer 29

lactic acid fermentation to generate ATP when O2 is scarce