Respiration

Question 1

the 2 types of respiration and how they differ

Answer 1

aerobic uses oxygen to fully oxidise glucose to CO2 and H2O producing more atp
anaerobic occurs without oxygen producing less atp and resulting in lactate in animals or ethanol and CO2 in plants and yeast

Question 2

where does glycolysis occur

Answer 2

cytoplasm

Question 3

steps of glycolysis

Answer 3

phosphorylation - glucose phosphorylated to glucose-6-phosphate using atp
lysis - splits into 2 triose phosphate molecules
oxidation - triose phosphate is oxidised to pyruvate producing NADH and ATP

Question 4

what are the net products of glycolysis per glucose molecule

Answer 4

2 ATP, 2 NADH, 2 pyruvate

Question 5

where does link reaction occur and what happens

Answer 5

mitochondrial matrix
pyruvate is decarboxylated and dehydrogenated to form acetyl-CoA, CO2 and NADH

Question 6

why is the link reaction necessary

Answer 6

converts pyruvate to acetyl-CoA, a substrate for the krebs cycle

Question 7

where does krebs cycle occur

Answer 7

mitochondrial matrix

Question 8

main steps of krebs cycle

Answer 8

acetyl-CoA combines with oxaloacetate to form citrate
citrate undergoes decarboxylation and dehydrogenation
NADH, FADH, ATP, and CO2 produced

Question 9

what are products of krebs cycle per acetyl-CoA

Answer 9

3 NADH, 1 FADH, 1 ATP, 2 CO2

Question 10

what is the role of the etc

Answer 10

transfers electrons from NADH and FADH through protein complexes, creating a proton gradient across the inner mitochondrial membrane

Question 11

the role of ATP synthase

Answer 11

uses the flow of protons via chemiosmosis to catalyse the formation of ATP from ADH and inorganic phosphate

Question 12

why is oxygen important in oxidative phosphorylation

Answer 12

oxygen is final electron acceptor, forming water and maintaining the flow of electrons

Question 13

how is NAD regenerated during anaerobic respiration in animals

Answer 13

pyruvate is reduced to lactate, regenerating NAD

Question 14

what are the byproducts of anaerobic respiration in plants and yeast

Answer 14

ethanol and CO2

Question 15

how much ATP is generated from the oxidation of one molecule of glucose in aerobic respiration

Answer 15

approximately 32-38 ATP, depending on conditions

Question 16

how are photosynthesis and respiration linked

Answer 16

photosynthesis produces glucose and oxygen, substrates for respiration. respiration produces CO2 and H2O, substrates for photosynthesis

Question 17

which processes involve ATP synthesis via chemiosmosis

Answer 17

oxidative phosphorylation

Question 18

what is the purpose of a respirometer

Answer 18

measure rate of oxygen consumption during respiration

Question 19

describe how a respirometer works

Answer 19

sealed chamber contains a living organism and a CO2 absorber (soda lime). as oxygen is consumed, pressure decreases, causing fluid in capillary tube to move

Question 20

how do you calculate the rate of respiration using a respirometer

Answer 20

measure distance fluid moves in capillary tube over time and calculate volume of oxygen consumed using tube’s cross sectional area

Question 21

what is the role of soda lime or potassium hydroxide in respirometer

Answer 21

absorbs CO2 to ensure only oxygen consumption is measured

Question 22

common variables to control in a respirometer experiment

Answer 22

temperature, organism size, oxygen concentration