Genetics And Plant Breeding - Study Mode

[#131] During mitosis, chromosomal DNA duplication takes place in
Correct Answer

(A) Interphase

Explanation

Solution: During mitosis, chromosomal DNA duplication takes place in Interphase. During interphase, the cell grows and the nuclear DNA is duplicated. The interphase is followed by the mitotic phase. During the mitotic phase, the duplicated chromosomes are segregated and distributed into daughter nuclei. The cytoplasm is usually divided as well, resulting in two daughter cells.

[#132] The histone proteins which are highly conserved is
Correct Answer

(B) H 2a , H 2b , H 3 , H 4

Explanation

Solution: The highly conserved histone proteins are H 2a , H 2b , H 3 and H 4 . Histones are highly basic proteins abundant in lysine and arginine residues that are found in eukaryotic cell nuclei. They act as spools around which DNA winds to create structural units called nucleosomes. The 4 'core' histones (H 2a , H 2b , H 3 and H 4 ) are relatively similar in structure and are highly conserved through evolution. They also share the feature of long 'tails' on one end of the amino acid structure - this being the location of a post-translational modification.

[#133] The relative humidity maintained in germination room is
Correct Answer

(D) 95 ± 2

Explanation

Solution: The relative humidity maintained in the germination room is 95 ± 2. Relative humidity of about 95% is recommended to maintain growing media moisture levels. Seed germination and growth to transplant size are usually the most critical stage of plant development. Providing an optimum environment with a germination cart or growth room will give uniform high-quality plants in less time.

[#134] Micronutrient are elements which are
Correct Answer

(A) Required by plants in small quantities

Explanation

Solution: Micronutrients are elements that are required by plants in small quantities. Micronutrients are essential dietary elements required by organisms in varying quantities throughout life to orchestrate a range of physiological functions to maintain growth and development. There are about seven nutrients essential to plant growth and health that are only needed in very small quantities, and these are B, Cl, Cu, Mn, Mo and Zn.

[#135] Development of the seed without sexual process is
Correct Answer

(A) Apomixix

Explanation

Solution: Development of the seed without sexual process is Apomixis. Apomixis is asexual reproduction without fertilization. Apomixis is the result of a plant gaining the ability to bypass the most fundamental aspects of sexual reproduction meiosis and fertilization. Without the need for male fertilization, the resulting seed germinates a plant that develops as a maternal clone.