Topic 2.2

Question 1

Bypass step 1

Answer 1

Pyruvate to PEP
pyruvate is phosphorylated in 2 steps

Pyruvate to oxaloacetate (malate to exit mitochondria) via enzyme pyruvate carboxylase (enzyme adds the carboxyl group)

oxaloacetate to PEP via enzyme Phosphoenolpyruvate carboxykinase (this enzyme moves the carboxyl group

Question 2

Bypass step 2

Answer 2

Glycolysis step 3
F6P to f16BP
basically just removes the phosphate
enzyme - phosphofructokinase - same as in glycolyis

Question 3

Bypass step 3

Answer 3

Glycolysis step 1
G6P TO Glucose
Removing the phopshate
enzyme is glucose-6-phosphatase

Question 4

glucose-6-phosphatase

Answer 4

Found in endoplasimic reticlum
very prominent in liver as the liver is responsible for blood glucose
not prominent in muscles or brain

Question 5

Precusors of pyruvate

Answer 5

Lactate
Alanine
amino acids

Question 6

Cori cycle

Answer 6

Uses lactate
most significant gluconeogenisis precusor
Lactate from the muscles goes into the blood and then into the liver
is then reoxidized back to pyruvate
pyruvate then undergoes gluconeogenesis back to glucose

Question 7

Amino Acid precusor

Answer 7

ie taking energy from the muscles
AA is converted to oxaloacetate of to pyruvate
then undergoes gluconeogenis
only amino acids that cant to this are lysine and leucine because they are not glucogeinc and can only be converted to acetyl coa

Question 8

Propionyl Coa

Answer 8

Comes from the breakdown of some amino acids and fatty acids
has an odd number of carbons (3)
Enters gluconeogenesis as succinyl coa

Question 9

Ethanol

Answer 9

Inhibits gluconeogenesis
causes hypoglyceamia (low blood sugar)
ethanol is metabolised in the liver - therefore undergoes lactate dehydrogenase excepts gets converted to lactate instead of pyruvate

Question 10

Gylcolysis control

Answer 10

3 regulatory steps

Question 11

Gluconeogenisis control

Answer 11

3 bypass steps

Question 12

regulation of Pyruvate carboxylase

Answer 12

Usally inactive
activated by a build of acetyl coa

Question 13

Regulation of fructose1,6bisphophatase

Answer 13

Inbited by AMP, ADP

Question 14

Regulation of glucose 6 phosphatase

Answer 14

stimulated by g6p
inhibited by hexokinase action

Question 15

F26BP regulator

Answer 15

regulator in the liver
inhibits fructose 1,6bisphosphatase but activates sister enzyme phosphofructokinase

Question 16

glycogen synthesis

Answer 16

occurs predominantly in liver and muscles
stored in muscles
amylo(1,4-1,6)transglycolyase - is the branching enzyme
takes a few glucose molecu;es of the end of a strand to create a new branch
Glycogen synthase is the second enzyme - takes udp glucose and attaches it to the new branch

Question 17

Polysaccharide metabolism

Answer 17

digestion in mouth
digestion in small intestine, alapha amylase cleaves internal bond
debranching enzyme takes the branches off