Carbohydrate Metabolism

Question 1

What are the crucial roles of Carbohydrates?

Answer 1

-Energy, Storage, Structure and Architecture of the cell

Question 2

What are the 3 main metabolic pathways concerned for carbohydrates?

Answer 2

• Oxydation in glycolosis reactions
• Oxydation in pentose phosphate pathway
• Storage as starch or glycogen (where their hydrolysis produces glucose)

Question 3

What is the original source of glucose for Plants?

Answer 3

Plants synthesize glucose and store it as starch in cell walls or convert it to sucrose/ fructose

Question 4

The functions of glucose in Animal Cells?

Answer 4

obtain saccharides from diet,and through neoglucogenes they obtain glucose which then can be ustored in the liver (glycogenesis) or continue to glycolysis or penose phosphate metabolic pathway.

Question 5

Pentose Phosphate Pathway

‘‘summarise the process’’

Answer 5

-oxidation of glucose->production of pentose for nucleic acids->production of NADPH and H+->production of ATP from NADPH and H+

Question 6

Pentose Phosphate Pathway can be divided into two phases

Answer 6

1. Oxidative phase

2. Non oxidative phase (the regeneration)

Question 7

Glycolysis

Answer 7

set of 10 reactions (oxidation of glucose in the cytosol by 2 molecules of pyruvate.
to produce NADH and ATP

Question 8

what happens to the pyruvate in aerobic conditions?

Answer 8

• conversion to glucose (gluconeogenis)
• stored as glycogen
• Oxydation in acetylCoA:irreversible route for the Krebs Cycle

Question 9

What happens to Pyruvate in anaerobic conditions?

Answer 9

• Lactate Production(lactate dehydrogenase catalyzes) which also regenerates NAD+ allowing glycolysis
• Alcohol Production : 1. decarboxylation by pyruvate decarboxylase as TPP being a coenzyme
  2. Redox reaction catalyses by alcohol dehydrogenase (ADH) using NAD+ AS COENZYME