C1.2 Cell respiration

Question 1

ATP structure

Answer 1

nucleid acid: base nucleotide structure (with adenine and ribose) + 2 additional phosphate groups (3 in total)

Question 2

How ATP provides energy?

Answer 2

energy is stored in bonds between phosphate groups which when broken can be used for energy

Question 3

What are the qualities of ATP to carry out its function?

Answer 3

-soluble in water so it can move freely
-not permeable
-stable at neutral pH

Question 4

To form ATP from ADP, the energy is required. Which molecules can be used to make ATP from ADP?

Answer 4

organic molecules like sugars and fatty acids

Question 5

What is aerobic cell respiration and how many ATP molecules are produced?

Answer 5

oxygen present respiration, 30+ ATP

Question 6

What is anaerobic cell respiration and how many ATP molecules are produced?

Answer 6

no oxygen present, 2 ATP

Question 7

ATP is short for…

Answer 7

adenosine triphosphate

Question 8

What is potential energy?

Answer 8

energy stored within a system

Question 9

What are the products of anaerobic respiration in humans?

Answer 9

lactic acid, 2 ATP

Question 10

What are the products of aerobic cell respiration?

Answer 10

carbon dioxide, water, 30+ ATP

Question 11

How NAD is reduced? (equation)

Answer 11

NAD+ + 2H+ + 2e —> NADH and H+

Question 12

What is glycolysis?

Answer 12

Break down of glucose into pyruvate with formation of ATP

Question 13

What is the difference between respiration, gas exchange and ventilation?

Answer 13

-respiration - production of ATP
-gas exchange - exchange of oxygen and carbon dioxide in and out of cell
-ventilation - breathing

Question 14

What are the products of anaerobic respiration in yeast?

Answer 14

carbon dioxide, ethanol

Question 15

Where aerobic respiration takes place?

Answer 15

cytoplasm, then mitochondria

Question 16

Where anaerobic respiration takes place?

Answer 16

cytoplasm only

Question 17

How cell respiration rate can be measured?

Answer 17

• CO2 concentration increase
  -O2 concentration decrease
  -glucose concentration decrease

Question 18

What is the main feature of electron carriers?

Answer 18

-they can be easily oxidised or reduced, meaning that can donate or accept electrons

Question 19

Where does link reaction take place?

Answer 19

matrix in mitochondria

Question 20

Where does Krebs cycle takes place?

Answer 20

matrix, mitochondria

Question 21

Where electron transport chain happen?

Answer 21

on the folds of inner membrane of mitochondria -cristae

Question 22

What is the substrate and the product of link reaction?

Answer 22

pyruvate (3C) —> acetyl (2C) -CoA

Question 23

Name 3 processes that happen in link reaction

Answer 23

-decarboxylation of pyruvate
-pyruvate is oxidised (lost H) and NAD is reduced to NADH forming acetyl group
-adding CoA

Question 24

What’s the byproduct after decarboxylation?

Answer 24

carbon dioxide

Question 25

What are electron carriers?

Answer 25

proteins in the inner membrane that easily gain and donate electrons

Question 26

How electron carriers receive an electron in electron transport chain?

Answer 26

NADH is oxidised into NAD and the electron carrier is reduced

Question 27

What happens to the electron received by electron carrier?

Answer 27

it can be pass to another electron carrier

Question 28

How proton pumps gain energy?

Answer 28

from energy released by moving the electron (from NADH) along the chain

Question 29

In what direction does proton pump (H+ work) pump protons?

Answer 29

from matrix into intermembrane space

Question 30

What is proton motive force?

Answer 30

accumulation of H+, which creates an electrochemical gradient

Question 31

How many protons can be pumped with use of energy from the electron from NADH?

Answer 31

10

Question 32

How many protons can be pumped with use of energy from the electron from FADH2?

Answer 32

6

Question 33

Chemiosmosis

Answer 33

movement of protons from high to low conc. through ATP synthase to make ATP from ADP

Question 34

What is ATP synthase and what is its function?

Answer 34

transmembrane channel protein for facilitated diffusion, acts as an enzyme to catalyse the conversion of ADP to ATP

Question 35

What mechanism in ATP synthase allows the conversion of ADP to ATP?

Answer 35

the part of the protein that rotates causes conformational change and create kinetic energy

Question 36

What is the role of oxygen in cell respiration?

Answer 36

-removes de-energised electrons -removes the matrix protons to form water

Question 37

Why oxygen is important at the end of electron transport chain?

Answer 37

-oxygen prevents blockage of the chain

Question 38

What's the order of processes in cell respiration?

Answer 38

-glycolysis -link reaction -Krebs cycle -electron transport chain