Respiration

Question 1

what is aerobic respiration

Answer 1

respiration in the present eof oxygen; has four stages glycolysis, link reaction, Krebs cycle, oxidative phosphorylation

Question 2

what is anaerobic respiration

Answer 2

respiration in the absence of oxygen, first stage is glycolysis, produces 2 molecules of ATP (net)

Question 3

what is a respiratory substrate

Answer 3

a molecule that can be broken down in respiration to release energy

Question 4

what is hexose

Answer 4

a sugar containing 6C

Question 5

what is glycolysis

Answer 5

breakdown of glucose into two molecules of triode phosphate, net gain of 2 ATP , formed by oxidative phosphorylation, two hydrogens removed and picked up by NAD to become reduced NAD, occurs in cytoplasm

Question 6

describe the link reaction

Answer 6

pyruvate is decarboxylated so one carbon is removed to produced CO2, NAD is reduced to NADH and acetate is combined with coenzyme A to form acetyl coenzyme A, no ATP produced

Question 7

what is the Krebs cycle

Answer 7

occurs in the matrix of the mitochondria, oxaloacetate joins with acetate to give citrate (6C) and releases coenzyme A, carboxyl groups are removed and hydrogen atoms too so the 4C compound is regenerated, cycle turns twice for each glucose molecule

Question 8

what is oxidative phosphorylation

Answer 8

producing pyruvate from glucose, split into stages: activation of glucose by phosphorylation, splitting of phosphorylated hexose sugar, oxidation of triode phosphate, production of ATP

Question 9

what is substrate level phosphorylation

Answer 9

when a phosphate group is directly transported from one molecule to another

Question 10

what is chemiosmosis

Answer 10

the movement of H+ ions by facilitated diffusion using ATP synthase from an area of high conc. in the intermediate space to high conc. in the matrix

Question 11

what is a coenzyme

Answer 11

a molecule which aids the function of an enzyme by transferring a chemical group

Question 12

what is NAD

Answer 12

transfers hydrogen from one molecule to another

Question 13

What is FAD

Answer 13

transfers hydrogen from one molecule to another

Question 14

What is ATP

Answer 14

adenosine triphosphate , nucleic acid which is the energy-carrying molecule that provides energy for cell activity

Question 15

What is phosphorylation

Answer 15

addition of phosphate group to a molecule

Question 16

What is dehydrogenation

Answer 16

two hydrogens are removed and used to reduce NAD to form NADH which is later used to produce ATP, enzyme involved is called pyruvate dehydrogenase

Question 17

Where is the cristae and what reactions occur here

Answer 17

mitochondria, site of chemiosmosis

Question 18

Where is the matrix and what reactions take place here

Answer 18

mitochondria, Krebs cycle, link reaction

Question 19

describe alcohol fermentation

Answer 19

occurs in yeast and produces ethanol, intermediate substance is ethanal, takes place in cytoplasm

Question 20

describe lactate fermentation

Answer 20

occurs in mammals and produces lactate, intermediate product is pyruvate (as first stage is glycolysis), takes place in cytoplasm

Question 21

what coenzymes are used in respiration

Answer 21

NAD, coenzyme a and FAD

Question 22

what does coenzyme a do

Answer 22

transfer acetate rom one molecule to another

Question 23

where does glycolysis take place and what type of process is it

Answer 23

cytoplasm of cells
anaerobic

Question 24

equation for lactate fermentation

Question 25

equation for alcohol fermentation

Question 26

give two examples of respiratory quotients

Answer 26

RQ= volume of Co2 released/volume of o2 consumed
RQ= molecules of Co2 released/molecules of O2 consumed