U2T1 - Keywords

Question 1

Oxidation

Answer 1

Gain of oxygen, loss of electrons, loss of hydrogen.

Question 2

Reduction

Answer 2

Loss of oxygen, gain of electrons, gain of hydrogen.

Question 3

Redox Reaction

Answer 3

When reduction + oxidation occur in the same reaction.

Question 4

Dehydrogenation

Answer 4

Removal of hydrogen.

Question 5

Decarboxylation

Answer 5

Removal of carboxyl group. (CO2)

Question 6

Phosphorylation

Answer 6

ATP synthesised from ADP + inorganic phosphate by condensation (removing 1 molecule water), making ATP energy rich. Addition of phosphate.

Question 7

Aerobic Respiration

Answer 7

Respiration using oxygen, releasing lots of ATP from glucose. Long term.

Question 8

Anaerobic Respiration

Answer 8

Respiration not using oxygen, releasing small amount of ATP from glucose + lactic acid/ethanol. Short term.

Question 9

ATP

Answer 9

Nucleotide ‘adenosine triphosphate’. Contains 3 phosphate groups with nucleotide base (adenine) + pentose sugar (ribose). Immediate + short term energy store. Has high free energy of hydrolysis. Drives metabolism.

Question 10

ADP

Answer 10

Adenosine Diphosphate.

Question 11

High free energy of hydrolysis

Answer 11

When ATP hydrolysed, large amount of energy released. Catalysed by ATPase.

Question 12

Substrate level phosphorylation

Answer 12

Direct transfer of phosphorylated substance to ADP. Occurs during krebs cycle + glycolysis. 1 molecule ATP produced from transfer of phosphate group from intermediate compound to ADP.

Question 13

Oxidative phosphorylation

Answer 13

ATP produced from ADP + Pi as electrons transferred along carriers - the ETC. Formation of ATP by oxidation of H atoms (lose electrons). Free phosphate groups. Energy required derived from redox reactions in ETC.

Question 14

Glycolysis

Answer 14

Splitting of hexose sugar (glucose) into 2 3-carbon pyruvate molecules. Occurs in aerobic + anaerobic resp as doesn’t require oxygen. Occurs in cytoplasm.

Question 15

NAD

Answer 15

Nicotinamide adenine dinucleotide. Coenzyme. When reduced, forms reduced NAD (NADH) Needed for dehydrogenases to pass on hydrogen they remove.

Question 16

Link Reaction

Answer 16

Before Kreb’s Cycle. Forms acetyl coenzyme A (acetyl CoA) from pyruvate to allow entry of 2 carbon molecule into mitochondrial matrix.

Question 17

Krebs Cycle

Answer 17

Involves cyclical series of reactions. ADP converted to ATP. Most energy released here. Feeding of acetyl CoA into cycle of oxidation + reduction.

Question 18

FAD

Answer 18

Flavin Adenine Dinucleotide. Hydrogen carrier.

Question 19

ETC

Answer 19

Electron Transport Chain. In cristae. Accepts H2 produced from Krebs cycle, link reaction + glycolysis by dehydrogenation. System made up of cytochromes + coenzymes which can pass on electrons produced from H2 splitting into electrons + protons (arrive as NADH and H+ and FADH2) + energy in H2 + electrons converted to ATP.

Question 20

Cytochrome oxidase

Answer 20

Enzyme responsible for passing H2 to O2, inhibited by cyanide.

Question 21

Beta Oxidation

Answer 21

Involves 2 carbon fragments being broken off fatty acids + converted to acetyl CoA.

Question 22

Acetyl CoA Stage

Answer 22

Point at which most respiratory substrates enter so considered hub of various respiratory pathways.

Question 23

Oxygen Debt

Answer 23

Reason why you continue to breath heavily after ceasing strenuous exercise. Lactate builds up + needs O2 to metabolise/convert to glucose so repays debt.

Question 24

Respiratory Quotient

Answer 24

RQ is ratio of volume of CO2 produced to volume of O2 used in respiration.

Question 25

Respirometer

Answer 25

Piece of apparatus used to measure resp rate.

Question 26

Energy

Answer 26

What is required to do work.

Question 27

Mitochondrial Matrix

Answer 27

Gel like matrix in mitochondrion, more viscous than the cell’s cytoplasm as it contains less water.

Question 28

Cytochromes

Answer 28

Compound consisting of haem bonded to protein. Function as electron transfer agents in metabolic pathways, especially respiration.

Question 29

Coenzyme Q

Answer 29

Electron transfer agent in respiration.

Question 30

Temperature Coefficient

Answer 30

Q10 = rate of reaction at (T + 10)°C/Rate of Reaction at T°C.
Generally for every 10°C rise, reaction rate doubles so usually 2.