Photorespiration and the quantum yield differ between C3 and C4 photosynthesis, with changes particularly noticeable as temperatures vary quantum yield for photosynthesis as a function of leaf temperature in C3 plants and C4 plants. Following are some statements  based on this study.

 a.) In the C4 plants the quantum yield remains constant with temperature, reflecting low rates of photorespiration

 b.) At lower temperatures the quantum yield of C3 plants is higher than that of C4 plants

c.) C3 photosynthesis is more efficient at lower temperatures

 d.) At higher temperatures the quantum yield of C3 plants is higher  than that of C4 plants

 Which one of the following combination of above statements is correct?

#Question id: 11848

#Unit 6. System Physiology – Plant

Polar transport is specific for active auxins, such as

#Question id: 11847

#Unit 6. System Physiology – Plant

On the basis of isotopic labeling and metabolite identification, oxidative pathways are more likely to be involved in the controlled degradation of IAA by____

Statement-I ___IAA is oxidized without decarboxylation to OxIAA

Statement-II___ IAA-aspartate conjugate is oxidized first to the intermediate dioxindole-3-acetylaspartate, and then to OxIAA

#Question id: 11846

#Unit 6. System Physiology – Plant

In maize  orange pericarp (orp) mutant is

#Question id: 11845

#Unit 6. System Physiology – Plant

IAA Is synthesized from__

#Question id: 11844

#Unit 6. System Physiology – Plant

The following statements are made to describe the biosynthetic pathway of IAA;

a)  IPA pathway involves a deamination reaction to form IPA, followed by a decarboxylation reaction to form indole-3-acetaldehyde (IAld) and then oxidized to IAA by a specific dehydrogenase

b) IAN pathway is similar to the IPA pathway, except that the order of the deamination and decarboxylation reactions is reversed, and different enzymes are involved

c) IAM pathway  involves the two enzymes  tryptophan monooxygenase and IAM hydrolase

d) In the IAN pathway, tryptophan is first converted to indole-3-acetaldoxime and then to indole-3-acetonitrile. The enzyme that converts IAN to IAA is called nitrilase

Which of the following is the correct  statements  of about the biosynthesis of  IAA?

#Question id: 10255

#Unit 6. System Physiology – Plant

In sucrose synthase combines sucrose with UDP to produce fructose and UDP-glucose in the cytosol. What is the function of UDP-glucose pyrophosphorylase?