glycolysis

Question 1

where about in cells does glycolysis take place?

Answer 1

the cytoplasm

Question 2

what shape of molecule does fructose usually form?

Answer 2

a furganose (5-membered ring)

Question 3

what is glucose coberted to in glycolysis?

Answer 3

pyruvate

Question 4

what shape of molecule is glucose usually found as?

Answer 4

hexose (6 membered ring)

Question 5

what is the first step of glycolysis?

Answer 5

phosphorylation of glucose to glucose -6- phosphate (CONSUMES ATP)

Question 6

how many steps of glycolysis are there?

Answer 6

nine

Question 7

what is the second step of glycolysis?

Answer 7

isomeriszation of glucose-6-phosphate to fructose-6-phosphate (i.e. the shape of the molecule is changed but the molecular formula remains the same)

Question 8

what is the third step of glycolysis?

Answer 8

phosphorylation of fructose-6-phosphate to fructose1.6 biphosphate (consumes ATP) - this forms a symmetrical phosphorylated compound that can easily be split into two

Question 9

what is the fourth step of glycolysis?

Answer 9

cleavage of fructose-6-phosphate to two molecules of glyceraldehyde 3 phosphate

Question 10

what is the fifth step of glycolysis?

Answer 10

oxidative phosphorylation: glyceraldehyde-3-P is simultaneously oxidised and phosphorylated into 1,3 biphosphoglycerate by the reduction of NAD to NADH
(NAD+ accepts hydrogen and electrons from glyceraldehyde-3-P)

Question 11

what does NAD stand for?

Answer 11

nicotinamide adenine dinucleotide

Question 12

what is the reactive group of NAD?

Answer 12

the nicotinamide group (can accept electrons)

Question 13

which vitamin provides this nicotinamide part of the NAD?

Answer 13

vitamin B3

Question 14

what does a lack of vitamin B3 cause?

Answer 14

Pellagra - sensiivity to sunlight, dermatitis, alopecia, glissitis, weakness, ataxia

Question 15

what is the 6th step of glycolysis?

Answer 15

transfer of a phosphate group to ADP to form ATP. 1,3 biphosphoglycerate becomes 3-phosphoglycerate (2 ATP produced)

Question 16

what is the seventh step of glycolysis?

Answer 16

3-phosphoglycerate is converted to 2-phosphoglycerate (MOLECULAR REARangemet)

Question 17

what is the 8th stage of glycolysis?

Answer 17

DEHYDRATION of 2-phosphoglycerate to phosphoenol pyruvate

Question 18

what is the 9th and last stage of glycolysis?

Answer 18

transfer of phosphate from phosphoenol pyruvate to ADP (PRODUCING 2 MOLECULES OF ATP) and 2 molecules of pyruvate

Question 19

how is NAD+ regenerated in AEROBIC conditions?

Answer 19

NADH passes the hydrogen and electrons through a system known as the ELECTRON TRANSFER CHAIN which combines therewith oxygen to form water

Question 20

how is NAD+ regenerated in ANAEROBIC conditions?

Answer 20

by reducing pyruvate to lactate (passing the electrons and hydrogen to pyruvate to make it lactate) (NB MUSCLE ACHES)

Question 21

which enzyme catalyses the phosphorylation of glucose to glucose-6-phosphate?

Answer 21

hexokinase

Question 22

which enzyme phosphorylates fructose-6-phophate to fructose-1,6-biphosphate?

Answer 22

phosphofructokinase

Question 23

which enzyme phosphorylates phosphoenolpyruvate to pyruvate?

Answer 23

pyruvate kinase

Question 24

what are three conditions that INHIBIT phosphofructokinase?

Answer 24

high ATP
low pH
high citric acid