Plant Pathology - Study Mode
[#181] Calvin cycle is
Correct Answer
(C) Supported by light
Explanation
Solution: Calvin cycle is supported by light. The Calvin cycle uses the chemical energy of ATP and the reducing power of NADPH from the light-dependent reactions to produce sugars for the plant to use. The Calvin cycle thus happens when light is available independent of the kind of photosynthesis, CAM plants store malic acid in their vacuoles every night and release it by day to make this process work.
[#182] Permeability of protoplasm is accelerated by
Correct Answer
(C) K
Explanation
Solution: The permeability of protoplasm is accelerated by K (Potassium). Potassium (K + ) is of paramount importance in plant cell physiology. K + is an essential macronutrient that fulfills critical functions related to enzyme activation, osmotic adjustment, turgor generation, cell expansion, regulation of membrane electric potential, and pH homeostasis.
[#183] Micrografting is used to produce plants free from
Correct Answer
(A) Virus
Explanation
Solution: Micrografting is used to produce plants free from viruses. An innovative technique of micrografting was developed by Murashige et al. (1972) for the production of uniform virus-free plants on a commercial scale in a controlled environment. They grafted a small apical shoot of citrus to the top of a decapitated seedling grown in vitro. Micropropagation can be used to produce disease-free plants. It produces rooted plantlets ready for growth, and saves time for the grower, instead of seeds or cuttings.
[#184] RuBISCO content of chloroplast is
Correct Answer
(D) 16%
Explanation
Solution: RuBISCO content of chloroplast is 16%. It is an enzyme involved in the first major step of carbon fixation, a process by which atmospheric carbon dioxide is converted by plants and other photosynthetic organisms to energy-rich molecules such as glucose. RuBisCO is slow, fixing only 3-10 carbon dioxide molecules each second per molecule of enzyme. The reaction catalyzed by RuBisCO is, thus, the primary rate-limiting factor of the Calvin cycle during the day.
[#185] Hordei viruses are
Correct Answer
(C) Tripartite
Explanation
Solution: Hordeiviruses are Tripartite. Tripartite is divided into or composed of three parts. Hordeivirus is a genus of viruses, in the family Virgaviridae. Plants serve as natural hosts. There are four species in this genus. Viruses in the genus Hordeivirus are non-enveloped, with rod-shaped geometries. The diameter is around 20 - 25 nm, with a length of 20 - 25 nm. Genomes are linear and segmented, tripartite or quadripartite, around 3.3 kb in length.