A) choose the two enzymes that together catalyze the net reaction:

a-ketoglutarate + nadp(h) + h+ + nh4+ + atp → glutamate

b) why doesn’t the glutamate dehydrogenase reaction contribute much to nitrogen assimilation under normal physiological conditions? (choose one answer in part b)

question 10 options:

a) glutamate dehydrogenase

a) glutamine synthetase

a) nitrogenase

a) glutamate synthase

a) α-ketoglutarate dehydrogenase

b)glutamate dehydrogenase catalyzes the same reaction, but only under conditions of very high nh4+ levels such as agricultural fertilizers since the reaction is unfavorable under standard conditions (δgº’ = +30kj/mol). under physiological conditions, this reaction deaminates glutamate.

b) glutamate dehydrogenase needs nadph for the reaction, which can be limiting under conditions where nitrogen assimilation is needed.

b) under aerobic conditions, glutamate dehydrogenase has a side reaction with o2 that is wasteful, and therefore organisms prefer to use a different pathway under most physiological conditions.

expert answer

glutamine synthetase-glutamate synthase

b)Glutamate dehydrogenase catalyzes the same reaction, but only under conditions of very high NH4+ levels such as agricultural fertilizers since the reaction is unfavorable under standard conditions (ΔGº’ = +30kJ/mol). Under physiological conditions, this reaction deaminates glutamate.

Explanation:

The importance of the first reaction you can see that it needs a molecule of ATP in order to create the catalysm, so that´s why that enzyme is called synthetase, since it needs a molecule of ATP to do its work, the other one, the glutamate synthetase, because it does not need the molecule of ATP to do so.

Glutamate can only catalyze the reaction under certain not found in nature regularly conditions, that´s why it doesn´t work as a dehydrogenase.

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.

as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.