Question

6)Cyclic electron flow through photosystem one and its associated electron transfer chain can be used to produce ATP when levels of ________ are very low.

7) As well as acting as a carboxylase, Rubisco can act as an oxygenase under normal environmental conditions initiating a pathway known as ________ which produces 3-phosphoglycerate and 2-phosphoglycolate.

Answer 1

6) Energy

Cyclic electron flow through photosystem one and is associated electron transfer chain can be used to produce ATP when level of energy are very low.

Because cyclic electron flow more productive than non cyclic electron flow with regard to ATP synthesis. So when energy level are very low then it occur to produce sufficient amount of ATP for proper functioning.

7) Photorespiration

RuBisCo is a bifunctional enzyme perform both carboxylase and oxygenase activity to catalyze the ribulose bisphosphate (RuBP).

When the carbon dioxide concentration is low then it perform oxgenase activity. Oxygenation of RuBP leads to production of one molecule of 2- phosphoglycolate and one molecule of 3- phosphoglycerate.