Plant Pathology - Study Mode

[#171] Enzymes of Krebs cycle occur in mitochondrial matrix except one which is attached to inner mitochondrial membrane
Correct Answer

(C) Succinate dehydrogenase

Explanation

Solution: Enzymes of the Krebs cycle occur in the mitochondrial matrix except one that is Succinate dehydrogenase which is attached to inner mitochondrial membrane. Succinate dehydrogenase is an enzyme complex, found in many bacterial cells and the inner mitochondrial membrane of eukaryotes. It is the only enzyme that participates in both the citric acid cycle and the electron transport chain. The reactions occur in the inner mitochondrial membrane by coupling the two reactions together.

[#172] How many rings are found in the flagella structure of Gram -ve bacteria?
Correct Answer

(D) 4

Explanation

Solution: 4 rings are found in the flagella structure of Gram-ve bacteria. Gram-negative organisms have four such rings: the L ring associates with the lipopolysaccharides, the P ring associates with the peptidoglycan layer, the M ring is embedded in the plasma membrane, and the S ring is directly attached to the plasma membrane.

[#173] The proportion of plant population affected by a disease is known as
Correct Answer

(C) Disease Intensity

Explanation

Solution: The proportion of the plant population affected by a disease is known as Disease Intensity. Disease intensity is a general term used to denote amount of disease, commonly expressed as either disease incidence (proportion of the total number of plants that are infected) or disease severity (proportion of total plant area that is infected). The disease severity is estimated by a rater as a value on the interval scale and has been used to determine a disease severity index (DSI) on a percentage basis, where DSI (%) = [sum (class frequency × score of rating class)] / [(total number of plants) × (maximal disease index)] × 100.

[#174] Mitochondria are sites of
Correct Answer

(A) Oxidative phosphorylation

Explanation

Solution: Mitochondria are sites of Oxidative phosphorylation. The breakdown of carbohydrates or fats is derived from oxidative phosphorylation, which takes place within mitochondria. As the production of reactive oxygen species by these proton-pumping complexes is greatest at high membrane potentials, it has been proposed that mitochondria regulate their activity to maintain the membrane potential within a narrow range that balances ATP production against oxidant generation.

[#175] Compensation point is the value of a factor where there is
Correct Answer

(C) Photosynthesis equal to rate of respiration

Explanation

Solution: The compensation point is the value of a factor where there is photosynthesis equal to the rate of respiration. The light compensation point ( I c ) is the light intensity on the light curve where the rate of photosynthesis exactly matches the rate of cellular respiration. At this point, the uptake of CO 2 through photosynthetic pathways is equal to the respiratory release of carbon dioxide, and the uptake of O 2 by respiration is equal to the photosynthetic release of oxygen.