cell respiration

Question 1

define redox reactions:

Answer 1

redox reactions are either reduction or oxidisation reactions.
-reduction reactions:
-gain on electrons
-loss of hydrogen
-no oxygen
-oxidation:
-loss of electrons
-gain of hydrogen
-oxygen

Question 2

define reduction:

Answer 2

-reduction reactions:
-gain on electrons
-loss of hydrogen
-no oxygen

Question 3

define oxidation:

Answer 3

-oxidation:
-loss of electrons
-gain of hydrogen
-oxygen

Question 4

what are electron carriers?

Answer 4

-molecules that are able to accept electrons, and then carry and transfer them to another point.

Question 5

what is glycolysis?

Answer 5

taking place in the cytoplasm, it is the first stage of anaerobic and aerobic respiration. phosphorolysis of glucose takes place, to produce 2 pyruvate molecules.

Question 6

what is phosphorylation?

Answer 6

this is where glucose is oxidised.

Question 7

what is lysis?

Answer 7

this is where one molecule of glucose, which contains 6 carbons, is broken down into 2 pyruvate molecules, that each have 3 carbons.

Question 8

what is pyruvate?

Answer 8

pyruvate is the product of glycolysis, that is used to bridge the gap to the krebs cycle.

Question 9

what is lactate?

Answer 9

lactate is produced in anaerobic respiration, when the glucose is not fully broken down. it causes muscle fatigue, and is broken down with the oxygen debt.

Question 10

what is NAD?

Answer 10

it is a carrier molecule, that is reduced, when it takes up electrons, and during aerobic respiration.

Question 11

what is reduced NAD?

Answer 11

Reduced NAD, or NADH, is the carrier of electrons, to the electron transport chain.

Question 12

Define aerobic respiration:

Answer 12

enzyme controlled reaction, that release energy, in the form of ATP. It also takes place in the presence of oxygen.

Question 13

Define anaerobic respiration:

Answer 13

the breakdown of glucose without oxygen, to release ATP.

Question 14

what is the link reaction?

Answer 14

a carbon atom is removed from pyruvate, forming carbon dioxide. This converts pyruvate into a two-carbon molecule called acetate. Hydrogen is also removed from pyruvate in the conversion into acetate, which is picked up by the coenzyme NAD to form reduced NAD.

Question 15

what is Decarboxylation?

Answer 15

the removal of a carbon atom

Question 16

what is Coenzyme A?

Answer 16

it is a coenzyme that binds an acetyl group to form acetyl coenzyme A during the link reaction of aerobic respiration.

Question 17

what is the krebs cycle?

Answer 17

it is a series of reactions which generate reduced NAD and a similar molecule called reduced FAD which are needed for oxidative phosphorylation

Question 18

what is Oxaloacetate?

Answer 18

it is the starting four carbon compound

Question 19

what is citrate?

Answer 19

it is a central metabolic pathway for aerobic organisms.

Question 20

what are Dehydrogenation Reactions?

Answer 20

this is where the two hydrogens picked up by NAD are released.

Question 21

what is the Mitochondrion?

Answer 21

the site of cellular respiration in cells.

Question 22

what is the Inner Mitochondrial Membrane?

Answer 22

it is the site for oxidative phosphorylation.

Question 23

what are Cristae?

Answer 23

they are folds in the inner mitochondrial membrane, that increase the surface area.

Question 24

what is the Matrix?

Answer 24

it is a site in the inner mitochondrial membrane, where the krebs cycle takes place.

Question 25

what are protons?

Answer 25

protons are what power the ATP synthase.

Question 26

what is the proton gradient?

Answer 26

The transfer of electrons creates a proton gradient that drives the flow of hydrogen ions across the inner membrane of mitochondria, which generates ATP through chemiosmosis.

Question 27

what is ATP synthase?

Answer 27

it is what transports the protons through the phospholipid bilayer. this provided energy to convert ADP to ATP.

Question 28

what is chemiosmosis?

Answer 28

it is the movement of ions across a membrane.