Plant Pathology - Study Mode

[#591] Rate of transpiration is measured by
Correct Answer

(D) Ganong's potometer

Explanation

Solution: The rate of transpiration is measured by Ganong's potometer. A potometer, is a device used for measuring the rate of water uptake of a leafy shoot which is almost equal to the water lost through transpiration. Francis DarwinCharles Darwin Ganong Bose designed and invented Ganong’s potometer. The Ganong's potometer is composed of a glass tube, which is bent twice, and a glass cylinder with a wide mouth also a capillary tube is inserted into a horizontal glass bar attached to a reservoir.

[#592] C 4 plants differ from C 3 plants in
Correct Answer

(A) Number of ATPs consumed per hexose molecule

Explanation

Solution: C 4 plants differ from C 3 plants in the number of ATPs consumed per hexose molecule. C 4 carbon fixation is one of three known photosynthetic processes of carbon fixation in plants while the C 3 cycle is a series of biochemical redox reactions that take place in the stroma of chloroplast in photosynthetic organisms. Both cycles require ATP for their process, but they differ in the number of ATP required. C 4 plants need 12 ATP's more than C 3 plants to synthesize per hexose molecule.

[#593] Nine-tenth of all photosynthesis of world (85 - 90%) is carried out by
Correct Answer

(B) Algae of the ocean

Explanation

Solution: Nine-tenth of all photosynthesis in the world (85 - 90%) is carried out by algae of the ocean. Algae are a diverse group of predominantly aquatic photosynthetic organisms, including cyanobacteria, green algae, and other eukaryotic algae. They account for 85 - 95% of the photosynthesis that takes place on Earth. Algae have a wide range of antenna pigments to harvest light energy for photosynthesis giving different types of algae their characteristic colour. Algae are indispensable because they produce about half the oxygen in Earth's atmosphere.

[#594] Leghaemoglobin per cent in the root nodules of leguminous plants helps in nitrogen fixation by
Correct Answer

(A) Removing oxygen

Explanation

Solution: Leghemoglobin present in the root nodules of leguminous plants helps in nitrogen fixation by removing oxygen. Leghemoglobin is an oxygen-carrying phytoglobin found in the nitrogen-fixing root nodules of leguminous plants. It is produced by these plants in response to the roots being colonized by nitrogen-fixing bacteria, termed rhizobia, as part of the symbiotic interaction between plant and bacterium roots not colonized by Rhizobium do not synthesise leghemoglobin. The main functions of leghemoglobin are to facilitate oxygen supply to the nitrogen-fixing bacteria and to protect the enzyme, nitrogenase from being inactivated by oxygen.

[#595] Selective media for Xanthomonas is
Correct Answer

(D) Yeast extract nutrient agar

Explanation

Solution: The selective media for Xanthomonas is yeast extract nutrient agar. A selective medium (XMSM) was developed for isolation of Xanthomonas maltophilia from bulk soil and plant rhizosphere environments. The XMSM basal medium contained maltose, tryptone, bromthymol blue and agar.