Q4. Assertion: photorespiration lowers CO fixation in C plants. Reason: when O binds RuBisCO, RuBP forms phosphoglycerate and phosphoglycolate instead of 2 molecules of PGA. Are both true, and does the reason explain the assertion?
Both are true, and the reason explains the assertion (NCERT page 147).
Q5. What decides whether CO or O binds to RuBisCO?
Their relative concentrations; the binding is competitive (NCERT page 147).
Q6. Give two benefits C plants gain from lacking photorespiration, according to NCERT.
Better productivity and yields; they also show tolerance to higher temperatures (NCERT page 147).