3.5.2 Respiration

Question 1

Answer 1

Question 2

what is the first overall stage of respiration

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

Question 7

Draw glycolysis

Answer 7

Question 8

What is the second stage of respiration?

Answer 8

The link reaction

Question 9

Answer 9

Question 10

What are the products of the link reaction?

Answer 10

CO2, Acetyl CoA, and NADH

Question 11

Answer 11

Question 12

Answer 12

Question 13

What are the products of one Krebs cycle?

Answer 13

ATP, 2 CO2, 3 NADH and FADH2

Question 14

What are the stages of respiration?

Answer 14

Glycolysis, link reaction, Krebs cycle, electron transport chain

Question 15

Where does glycolysis happen?

Answer 15

Cell cytoplasm

Question 16

How many times do the Link reaction and Krebs cycle occur for every glucose molecule?

Answer 16

Twice

Question 17

What happens during glycolysis?

Answer 17

Triose phosphate is oxidised forming 2 pyruvate molecules. 2 NAD molecules are reduced to 2 NADH. 4 ATP are produced but the net gain is 2ATP

Question 18

What is released from NADH and FADH2 when they are oxidised?

Answer 18

Hydrogen atoms

Question 19

What is oxidative phosphorylation ?

Answer 19

The process where the energy carried by electrons from NADH and FADH2 is used to make ATP in the electron transport chain

Question 20

What is the energy released from electrons as they move down their electron transport chain in respiration used for?

Answer 20

Used by electron carriers to pump H+ ions into the intermembrane space

Question 21

How is ATP made in electron transport chain ?

Answer 21

H+ ions move down the electrochemical gradient back into the mitochondrial matrix via the ATP synthase enzyme. This movement drives the synthesis of ATP

Question 22

What is the final electron acceptor in respiration ?

Answer 22

O2

Question 23

What happens to lactate after a period of anaerobic respiration?

Answer 23

Lactate is oxidised back into pyruvate. It is directly oxidised into CO2 and H2O via Krebs Cycle, releasing energy to synthesise ATP. Some lactate is converted to glycogen and stored in muscle or liver cells.

Question 24

What is aerobic respiration?

Answer 24

splitting of glucose to release CO2 as a waste product and combining H2 with atmospheric O2 with the release of a large amount of energy

Question 25

Why does the Link reaction occur in the mitochondrial matrix?

Answer 25

the enzymes and coenzymes needed are locate here. NADH made is in the right place to be used by oxidative phosphorylation

Question 26

How is acetate made from pyruvate ?

Answer 26

Pyruvate is carboxylated as one carbon atom is removed to form CO2 and then NAD is reduced by collecting hydrogen from pyruvate to form acetate

Question 27

What are the products of anaerobic respiration in plants, animals and yeast?

Answer 27

In plants and yeast - pyruvate + NADH --> ethanol + CO2 + NAD. In animals - pyruvate + NADH --> lactate + NAD

Question 28

How is NAD regenerated in anaerobic respiration in humans

Answer 28

pyruvate is reduced (and forms lactate), the NADH is oxidised back into NAD

Question 29

What are the folds in the inner membrane of mitochondria called?

Answer 29

Cristae

Question 30

What is substrate level phosphorylation and when does it occur

Answer 30

THe production of ATP through a direct chemical reaction. It occurs in the last stage of glycolysis and during the krebs cycle. Overall 4 moleucles of ATP are made via this process in aerobic respiration

Question 31

Answer 31

Question 32

describe the structural adaptations of the mitochondria

Answer 32

Question 33

What are some similarities between the chloroplast and mitochondria

Answer 33

Both have circular and naked DNA. Both have 70s ribosomes and a double membrane. They both contain extensively folded membrane system to provide a large surface area for proteins of their electron transport chains

Question 34

What is the consequence of uncoupling proteins (or uncoupling chemicals) being added to the mitochondrial inner membrane

Answer 34

Some protons can leak back into the mitchnodrial matrix without going through ATP synthase. This causes a greater proportion of chemical energy in glucose to be released as heat energy.

Question 35

Define chemiosmosis

Answer 35

The movment of H+ ions down an electrochemical gradient through ATP synthase

Question 36

Cyanide CN- ions bind to the final protein in the electron transport chain instead of oxygen. What is the consequence

Answer 36

All the proteins in the electron transport chain become reduced and pumping of protons ceases. No ATP can be made by ATP synthesis and the cell will either switch to anaerobic respiration or die.

Question 37

Answer 37

Question 38

Answer 38

Question 39

Answer 39

Question 40

compare and contrast anaerobic respiration in human cells and yeast cells

Answer 40

Question 41

Answer 41