glycolysis

Question 1

___ will give you the most energy, but quickest energy comes from ____

Answer 1

lipids, carbohydrates

Question 2

what is glycolysis

Answer 2

enzymatic conversion of glucose into pyruvate

Question 3

the glycolysis pathway is highly _____

Answer 3

conserved

Question 4

why are there phosphorylated intermediates in glycolysis

Answer 4

1. keeps intermediates in cell
2. phosphate will be transferred to ADP (to drive reaction forward)
3. enzymatic handles (enzymes can recognize them)

Question 5

glucose to glucose-6-phosphate uses what enzyme

Answer 5

kinase (adds phosphate)

Question 6

the first four steps of glycolysis are ____ phase

Answer 6

preperatory

Question 7

phosphorylation of glucose which is catalyzed by hexokinase (irreversible)

Answer 7

step 1: the hexokinase reaction

Question 8

humans have __ isozymes of hexokinase

Answer 8

4

Question 9

glucokinase (in liver) does not have high affinity for glucose; why?

Answer 9

the liver gives the glucose to the brain so glucose needs to stay in liver to be sent

Question 10

the step 1 of glycolysis is a __ ___ where OH at C6 attacks g phosphate of ATP. The bound Mg++ facilitates the process (cell uses ATP in this step)

Answer 10

group transfer

Question 11

step 2 of glycolysis is (involves ring opening and Mg++ for stabilization)

Answer 11

isomerization og Glucose 6 phosphate to fructose 6 phosphate;

Question 12

the isomerize reaction goes from ___ to ketose

Answer 12

aldose

Question 13

step 3 is the ___ _ _ ___ ; second priming step (first committed step in glycolysis)

Answer 13

point of no return

Question 14

what happens in step three

Answer 14

fructose-6-phosphate goes to fructose 1,6-biphosphate by enzyme phosphifructokinase

Question 15

high levels of ATP decrease activity of phosphofructokinase, why?

Answer 15

we have plenty of energy so there is no reason to break down glucose

Question 16

step 4 of glycolysis is what

Answer 16

fructose 1,6 biphosphate to 2 3-carbon products

Question 17

step 4 has large delta G but goes forward because

Answer 17

products are quickly removed by next step

Question 18

the enzyme in step 4 is; gives you ___ and ___

Answer 18

aldolase; DAP-ketose and GAP-aldose

Question 19

step five of glycolysis is ____ and enzyme is ____

Answer 19

isomerization and triose phosphate isomerase

Question 20

what substrate GAP is used for next enzyme; DAP is converted to ___

Answer 20

GAP

Question 21

step 6 is ____ reaction and first energy yeilding step in glycolysis

Answer 21

GADPH

Question 22

GAD + inorganic phosphate (oxidation of the aldehyde) with NAD+ gives

Answer 22

NADH

Question 23

step 6 yields

Answer 23

1,3-biphosphoglycerate

Question 24

the oxidation step of glycolysis is ___ but the formation of acyl-phosphate is ____

Answer 24

favorable, unfavorable

Question 25

NAD is an electron carrier that carries _ electrons

Answer 25

2

Question 26

ratio in cytosol of NAD+ to NADH is kept

Answer 26

high

Question 27

the + in the NAD+ refers to the ___ form

Answer 27

oxidized

Question 28

high ratio of NADH in cytoplasm means __ ___; which will inhibit glycolysis

Answer 28

high energy

Question 29

substrate level phosporylation combines an unfafvorable with a

Answer 29

favorable

Question 30

generation of ATP from ADP and reactive chemical intermediates using soluble enzymes

Answer 30

substrate level phosphorylation

Question 31

step 7 drives step __ by keeping levels of 1,3-BPG low (product removal)

Answer 31

6

Question 32

enzymes that shift functional groups are called

Answer 32

mutases

Question 33

the goal of step 9 is to make the 2-phosphoglycerate a better

Answer 33

phosphate donor

Question 34

pyruvate kinase requires metals such as; its activity limited by this under physiological conditions

Answer 34

mg 2+

Question 35

amount of ATP from pay off phase is ___ but total net ATP is __

Answer 35

4;2

Question 36

if you do glycolysis at a high rate you are depleting ___ and without it you cannot do the pathway

Answer 36

NAD

Question 37

pyruvate gets converted to lactate by

Answer 37

lactate dehydrogenase

Question 38

the conversion of pyruvate to lactate regenerates

Answer 38

NAD

Question 39

the fermentation reaction (pyruavte --> lactate) does not use ___ or change NAD+/NADH ratio

Answer 39

O2

Question 40

starch and glycogen from your diet can be digetsed by ____ and make ____ + ____ as products

Answer 40

amylases; dextrins and glucose

Question 41

stored starch/glycogen is _____

Answer 41

hydrolyzed

Question 42

making glucose-phosphate from stores starch and glycogen _____ energy

Answer 42

conserves (cause phosphate is already present before it goes into glycolysis)

Question 43

dietary sugar products make what products

Answer 43

glucose + fructose/ galactose