Genetics And Plant Breeding - Study Mode
[#441] The 'one gene one enzyme' hypothesis was proposed by
Correct Answer
(A) Beadle and Tatum
Explanation
Solution: The 'one gene-one enzyme hypothesis was proposed by Beadle and Tatum. The one gene-one enzyme hypothesis is the idea that genes act through the production of enzymes, with each gene responsible for producing a single enzyme that in turn affects a single step in a metabolic pathway. The concept was proposed by George Beadle and Edward Tatum in an influential 1941 paper on genetic mutations in the mold Neurospora crassa and subsequently was dubbed the "one gene-one enzyme hypothesis".
[#442] Which of the following material makes the protein chain?
Correct Answer
(A) Amino acids
Explanation
Solution: Amino acids make the protein chain. A protein molecule is made from a long chain of these amino acids, each linked to its neighbor through a covalent peptide bond. Proteins are therefore also known as polypeptides. Each type of protein has a unique sequence of amino acids, the same from one molecule to the next.
[#443] There is an increase in . . . . . . . . under drought conditions
Correct Answer
(D) All of these
Explanation
Solution: There is an increase in ABA content, Ethylene content, and also proline content under drought conditions. Under drought stress, ABA levels were found to be significantly enhanced in the developing seed. Under drought, the production of ethylene increases and results in an initial increase, drought induces the de novo synthesis of ACS, the rate-controlling enzyme of the ethylene biosynthesis pathway. Proline accumulates in the leaf under drought stress. Compared to roots and stems, the proline content of the leaf was higher by 1 h post-drought stress and reached the peak.
[#444] ISTA formulated rules for
Correct Answer
(A) Seed testing
Explanation
Solution: ISTA formulated rules for Seed testing. ISTA stands for International Rules for seed testing. The ISTA Rules are the key element of ISTA's vision to achieve uniformity in seed testing and include testing methods for seeds designated for crop or plant production. The ISTA Rules are approved and amended at the ISTA Ordinary Meetings, based on advice from the ISTA Technical Committees. The procedures for the validation of test methods are given in the ISTA Method Validation Programme.
[#445] Removal of water vapour from the air in stored food grains is
Correct Answer
(C) Dehumidification
Explanation
Solution: Removal of water vapour from the air in stored food grains is Dehumidification. Dehumidification is a highly energy-intensive process, especially in humid climates and for building typologies that require strict space humidity set points. Sub-cooling of air to condense out the moisture using chilled water or refrigerant is the most common method for dehumidifying.