Nitrogen Metabolism

Question 1

Free AA are absorbed in the intestines by what mechanism of transport? Similar to?

Answer 1

Secondary active transport

Glucose and galactose

Question 2

Excretion of excess nitrogen as:

1. Ammonia
2. Urea
3. Uric acid

Answer 2

Ammonotelic- telostean fish
Ureotelic
Uricotelic- birds, semisolid guano!

Question 3

Transamination occurs in?

Answer 3

All cells

Question 4

AA involved in transamination

Answer 4

Glutamate - alpha ketogkutarate
Alanine- pyruvate
Aspartate- oxaloacetate

Question 5

Enzyme involved in alanine-> Pyruvate transamination

Answer 5

Alanine amino transferase

Question 6

Enzyme involved in aspartate transferase

Answer 6

Aspartate-> OAA

Question 7

Oxidative deamination occurs in?

What substrate?

Enzyme?

Answer 7

Liver and kidney

Glutamate

Glutamate dehydrogenase

Question 8

AA that pick up excess nitrogen from tissues

Answer 8

Glutamine (glutamate -> glutamine)

Alanine (glucose-alanine cycle)

Question 9

Enzyme that deaninates glutamine to ammonium

Where are these found?

Answer 9

Glutaminase

Kidneys and SI

Question 10

Normal protein turnover?

Answer 10

300-400 g per day