Genetics And Plant Breeding - Study Mode

[#521] Source of dwarfing gene in wheat is
Correct Answer

(B) Norin-10

Explanation

Solution: The Source of dwarfing gene in wheat is Norin-10. Norin 10 wheat is a semi-dwarf wheat cultivar with very large ears that was bred by Gonjiro Inazuka at an experimental station in Iwate Prefecture, Japan. Its parents were a semi-dwarf Japanese landrace that may have originated in Korea in the 3 rd or 4 th century AD, and two varieties from the USA. The Rht1 and Rht2 genes have been used in wheat breeding programs worldwide to provide shorter plants with higher yields. Norin 10 was also provided to the International Maize and Wheat Improvement Center in Mexico.

[#522] An amino acid which has related to drought tolerance in plants
Correct Answer

(B) Proline

Explanation

Solution: An amino acid which has related to drought tolerance in plants Proline. Proline, an amino acid, plays an important role in plants. It protects the plants from various stresses and also helps plants to recover from stress more rapidly. When applied exogenously to plants exposed to stress, Proline results in increased growth and other physiological characteristics of plants.

[#523] Pollination and fertilization in an unopened flower bud is the situation called
Correct Answer

(A) Cleistogamy

Explanation

Solution: Pollination and fertilization in an unopened flower bud is a situation called Cleistogamy. Cleistogamy is a type of automatic self-pollination of certain plants that can propagate by using non-opening, self-pollinating flowers. The principal advantage of cleistogamy is that it requires fewer plant resources to produce seeds than chasmogamy because the development of petals, nectar, and large amounts of pollen is not required.

[#524] One diploid individual has total DNA content 2C which increases to 4C before the onset of mitosis. At anaphase, the DNA content is
Correct Answer

(B) 2C

Explanation

Solution: One diploid individual has a total DNA content of 2C which increases to 4C before the onset of mitosis. At anaphase, the DNA content is 2C. The DNA amount in the unreplicated gametic nucleus of an organism is referred to as its C-value, irrespective of the ploidy level of the taxon. The DNA content is 2C, where C is defined as the mass of DNA present in a haploid chromosome set. As in the anaphase stage of mitosis, the diploid cell becomes haploid thus, the DNA content is also halved from 4C to 2C.

[#525] Adaptation is
Correct Answer

(A) A process of adjustment of individual to their environment by means of special structure

Explanation

Solution: Adaptation is a process of adjustment of the individual to their environment using a special structure. It is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Also it is a phenotypic trait or adaptive trait, with a functional role in each organism, and is maintained and has evolved through natural selection.