Carbohydrate Metabolism

Question 1

Glycolysis name

Answer 1

Embden-Myerhoff pathway

Question 2

Glycolysis reaction

Answer 2

1 glucose -> 2 pyruvate + 2 NADH + 2 ATP

Question 3

Glycolysis

Answer 3

• Occurs in cytosol
• 10 reactions
• Substrate level phosphorylation

Question 4

Fate of pyruvate in aerobic condition

Answer 4

Pyruvate + CoA + NAD+ -> Acetyl CoA + CO2 + NADH

Enzyme: pyruvate dehydrogenass

Question 5

Fate of pyruvate in anaerobic condition

Answer 5

Pyruvate + NADH Lactic acid + NAD+

Enzyme: Lactate dehydrogenase

Question 6

Tissue in which end product of glycolysis does not proceed to aerobic respiration

Answer 6

Muscle

Question 7

Cori cycle

Answer 7

Cycling of lactate between muscle and liver
• Lactate in muscle transported to liver
• Liver converts it to glucose
• Glucose reenters bloodstream, used by muscle

Question 8

Krebs cycle location

Answer 8

Matrix of mitochondria

Question 9

Krebs cycle function

Answer 9

• Further oxidation of acetyl CoA

* Produce energy as ATP or as NADH and FADH2, which are oxidised by ETC to produce ATP

Question 10

Reactions of TCA

Answer 10

• Acetyl CoA combines with oxaloacetate to form citrate
For each acetyl CoA that enters cycle,
• 3 NADH and 1 FADH2 are produced
• 1 ATP formed by substrate level phosphorylation
• 2 CO2 released

Question 11

Gluconeogenesis

Answer 11

Synthesis of glucose from non-carbohydrate compounds

Question 12

Gluconeogenesis location

Answer 12

Liver, kidney (NOT muscle)

Cytosol, mitochondria of cells

Question 13

Glycogen synthesis and degradation location

Answer 13

Liver, muscle

Cytosol of cells

Question 14

Glycogen synthesis enzymes

Answer 14

• Hexokinase/glucokinase

* Glycogen synthase branching enzyme

Question 15

Glycogenolysis enzymes

Answer 15

• Glucose 6-phosphatase

* Glycogen phosphorylase debranching enzyme

Question 16

Pentose phosphate pathway name

Answer 16

Hexose monophosphate shunt

Question 17

Pentose phosphate pathway location

Answer 17

Cytosol of cells

Question 18

Pentose phosphate pathway function

Answer 18

• Oxidation of glucose, but not for energy
• Produce NADPH for synthesis of fatty acid, cholesterol
• Produce ribose-5-phosphate for nucleotide, nucleic acid synthesis

Question 19

Pentose phosphate pathway enzymes

Answer 19

1st step of oxidatice phase catalysed by glucose-6-phosphate dehydrogenase

Question 20

Liver glycogen function

Answer 20

Maintain blood glucoss

Question 21

Muscle glycogen function

Answer 21

Provide glucose 6-phosphate for muscle energy requirements (intermediate in glycolytic pathway)

Question 22

Organs without glucose-6-phosphatase

Answer 22

Kidneys and muscle