BSI Lecture 31 Glycolysis and Lactic Acidosis

Question 1

What cellular process uses the most ATP?

Answer 1

1. Protein synthesis 27%
2. Na+/K+ ATPase 24%
3. Gluconeogenesis 9%
4. Ca2+ ATPase 6%
5. Myosin ATPase 5%
6. Ureagenesis 3%

Question 2

________ refers to all chemical reactions occurring in the body (usually ordered in metabolic pathways).

Answer 2

Metabolism

Question 3

_______ reactions release energy stored in organic molecules.

Answer 3

Catabolic

Question 4

_______ reaction refers to catabolic reactions.

Answer 4

Exergonic

Question 5

_______ reactions are synthesis reactions that consume energy

Answer 5

Anabolic

Question 6

______ reactions refers to Anabolic reactions.

Answer 6

Endergonic

Question 7

If “foodstuff” was oxidized in one reaction, what would happen to the energy?

Answer 7

It would be lost as heat and no energy would be stored

Question 8

T or F? If “foodstuff” is oxidized in a stepwise manner, the free energy released can be stored in ATP.

Answer 8

True

Question 9

T or F? Stepwise manner stores energy in ATP, ATP is then used for exergonic reactions.

Answer 9

False, used for endergonic reactions

Question 10

This process is an incomplete oxidation of sugar.

Answer 10

Glycolysis

Question 11

Energy comes from the breaking of _______ _______

Answer 11

Chemical bonds

Question 12

In glycolysis, 1 glucose will turn into how many pyruvates?

Answer 12

2

Question 13

Using oxygen, _______ can then enter the mitochondria for further oxidation.

Answer 13

Pyruvate

Question 14

_______ produces immediate energy.

Answer 14

Glycolysis

Question 15

______ is limiting in its abiity to continuously meet demands of cell.

Answer 15

Glycolysis

Question 16

Where does glycolysis occur in cell?

Answer 16

Cytosol

Question 17

What is the net ATP produced in glycolysis?

Answer 17

2

Question 18

Glycolysis: Glucose is phosphorylated by what enzyme.

Answer 18

Hexokinase (Glucokinase if in the liver)

Question 19

In the liver, the enzyme that phosphorylate glucose is called ______

Answer 19

Glucokinase

Question 20

Glucose-6-phosphate is turned into what by Glucose-6-phosphate isomerase?

Answer 20

Fructose-6-phosphate

Question 21

Fructose-6-phosphate is phosphorylated by what enzyme?

Answer 21

Phosphofructokinase (PFK)

Question 22

After PFK has phosphorylated, what is the product?

Answer 22

Fructose-1,6-bisphosphate

Question 23

How many carbons does fructose have?

Answer 23

6

Question 24

Glycolysis: The fructose molecule is split into 2 molecules by what enzyme.

Answer 24

Aldolase

Question 25

Glycolysis: Two molecules are produced from fructose splitting, what are they?

Answer 25

Glyceraldehyde-3-phosphate and dihydroxyacetone phosphate

Question 26

Dihydroxyacetone phosphate is isomerized into a second molecule of glyceraldehyde-3-phosphate by what enzyme?

Answer 26

Triosephosphate isomerase

Question 27

Glyceraldehyde-3-phosphate is oxidized and then phosphorylated by _________`

Answer 27

Glyceraldehyde-3-phosphate dehydrogenase

Question 28

T or F? Glyceraldehyde-3-phosphate is phosphorylated into 1,2-biphosphoglycerate.

Answer 28

False, 1,3-diphosphoglycerate

Question 29

What else is produced after Glyceraldehyde-3-phosphate is phosphorylated?

Answer 29

NADH + H+

Question 30

Glyceraldehyde-3-phosphate is phosphorylated by what enzyme?

Answer 30

Glyceraldehyde-3-phosphate dehydrogenase

Question 31

After phosphoglycerate kinase phosphorylates, what are the products made?

Answer 31

3-phosphoglycerate and ATP

Question 32

Where does the phosphate come from when 3-Phophoglycerate + ATP is produced?

Answer 32

1,3 biphosphoglycerate donates a phosphate to ADP

Question 33

Phosphoglycerate mutase rearranges 3-phosphoglycerate into ____________

Answer 33

2-phosphoglycerate

Question 34

Enolase removes H20 from 2-phosphoglyerate to produce _____.

Answer 34

phosphoenolpyruvate

Question 35

Pyruvate and ATP are produced after _____________ kinase removes a phosphate from _______ to phosphorylate ATP.

Answer 35

Pyruvate; phosphoenolpyruvate

Question 36

In the Glycolytic pathway, which 2 steps utilizes ATP?

Answer 36

1. When hexokinase phosphorylates glucose. | 2. When phosphofructokinase phosphorylates fructose 6-phosphate.

Question 37

In the Glycolytic pathway, which 2 steps is ATP created?

Answer 37

1. When phosphoglycerate kinase phosphorylates ATP by removing a phosphate from 1,3diphosphoglycerate. 2. When pyruvate kinase phosphorylates ATP by removing phosphate from phosphoenolpyruvate.

Question 38

In the Glycolytic pathway, which step does 2 NAD+ and 2 phosphate come into play?

Answer 38

When glyceraldehyde 3-phosphate dehydrogenase phosphorylates glyceraldehyde 3-phosphate.

Question 39

What does NAD+ do to glyceraldehyde 3-phosphate?

Answer 39

Strips electrons and transport it to the ETC

Question 40

T or F? Pyruvate can be oxidized into lactate by lactate dehydrogenase.

Answer 40

False, reduced.

Question 41

Oxidation is the _____ of electrons. | Reduction is the _____ of electrons.

Answer 41

``` Oxidation is the _____ of electrons. Reduction is the _____ of electrons. Loss; Gain (OIL RIG Oxidation Is Loss Reduction Is Gain) ```

Question 42

Lactate dehydrogenase reduces pyruvate+NADH+H into _____ + _____.

Answer 42

lactate + NAD+

Question 43

Anaerobic glycolysis: ___ glucose ---> ___ pyruvate ---> ___ lactate (nets ___ ATP) [fill in with numbers]

Answer 43

1;2;2;2

Question 44

T or F? Anaerobic glycolysis is complete oxidation of glucose

Answer 44

False, incomplete

Question 45

Anaerobic glycolysis occurs if _____ NOT available.

Answer 45

oxygen

Question 46

T or F? Pyruvate enters the nucleus for further oxidation only if oxygen is available.

Answer 46

False, mitochondria

Question 47

What is the purpose of reducing pyruvate to lactate during anaerobic conditions?

Answer 47

Important because NADH needs to recycled to NAD+ to grab electrons

Question 48

What can happen to the build up of lactate?

Answer 48

1. Other cells/tissues that are better oxygenated can take it up and use it for energy. 2. Liver can take it up and use it for gluconeogenesis. 3 Can be eliminated by kidneys

Question 49

A drop in pH resulting from condition where the production of H+ exceeds the removal of H+ accompanied by a build-up of lactate in the blood is called ______ _____

Answer 49

Lactic acidosis

Question 50

Regulation of glycolysis: ____ must be maintained within limits.

Answer 50

ATP

Question 51

What are the regulation of glycolysis?

Answer 51

1. Rate limiting enzymes 2. Things that stimulate glycolysis: ADP & Pi (low energy status), inisulin, epinephrine. 3. Things that inhibits glycolysis: ATP (high energy status) and glucagon.

Question 52

T or F Glucagon inhibits glycolysis only in the liver; glucagon has no effect in other tissues.

Answer 52

True

Question 53

What are the rate limiting enzymes?

Answer 53

1. Hexokinase 2. PFK 3. Pyruvate kinase

Question 54

High blood glucose levels, among other things, stimulate secretion of _____ from pancreatic B-cells.

Answer 54

Insulin

Question 55

T or F? Insulin stimulates uptake of blood glucose by various tissues and stimulates catabolic reactions.

Answer 55

False, anabolic

Question 56

T or F? Insulin inhibits catabolic reactions.

Answer 56

True

Question 57

T or F? The brain does not need insulin to take up glucose.

Answer 57

True

Question 58

Low blood glucose levels, stimulate secretion of ______ from pancreatic alpha-cells.

Answer 58

Glucagon

Question 59

Glucagon stimulates ______ reactions and inhibits ____ reactions.

Answer 59

catabolic; anabolic

Question 60

______ leads to the accumulation of lactate.

Answer 60

hypoxia