Genetics And Plant Breeding - Study Mode

[#876] Match the following columns: Column I (Name of the crop) Column II (Name of the hybrid varity) a. Pearl millet (Bajra) 1. CSH-1 b. Maize 2. Pusa RH-10 c. Basmati rice 3. HB-1 d. Sorghum 4. Ganga-1
Correct Answer

(B) a-3, b-4, c-2, d-1

Explanation

Solution: a. HB-1 is the hybrid variety of Pearl millet. The first pearl millet hybrid HB 1 was released in 1965 thus making India the first country in the world to develop a grain hybrid utilizing a cytoplasmic-genetic male-sterile line and a restorer line. b. Ganga-1 is the hybrid variety of Maize. The first hybrid maize Ganga-1 was developed in India in 1961. c. Pusa RH-10 is the hybrid variety of Basmati rice. Pusa Rice Hybrid 10 (PRH 10) is the first aromatic Basmati Hybrid developed by the public sector Agricultural Research Institute and released by Central Variety Release Committee (CVRC) in 2001. d. CSH-1 is the hybrid variety of Sorghum. The first sorghum hybrid, CSH1 (Coordinated Sorghum Hybrid), was bred in India and officially released for commercial cultivation in 1964.

[#877] The number of single crosses will be equal to
Correct Answer

(A) $$frac{{{ ext{n}}left( {{ ext{n}} - 1} ight)}}{2}$$

Explanation

Solution: The number of single crosses will be equal to $$frac{{{ ext{n}}left( {{ ext{n}} - 1}
ight)}}{2}.$$ The term "single cross" means the first-generation hybrid between two inbred lines. The type of hybrid that is produced when two different inbreds are cross-pollinated, which is also known as an F1 hybrid, are inbreds. Each seed produced from crossing two inbreds has an array (collection) of alleles from each parent.

[#878] Mitotic apparatus consists of
Correct Answer

(D) All of the above

Explanation

Solution: Mitotic apparatus consists of a Mitotic spindle, Aster ray along the centriole,and Matrix. The mitotic spindle apparatus is a microtubule-based structure responsible for chromosome segregation during cell division. Microtubules within the spindle are classified according to their plus-end interactions. The mitotic spindle is a special device essential for chromosome segregation (mitosis) during cell division. In eukaryotic cells, the mitotic apparatus is composed of two centrosomes and spindle microtubules. The centrosome is 1 - 2 μm in diameter.

[#879] Longest phase of Mitosis is
Correct Answer

(A) Prophase

Explanation

Solution: The longest phase of Mitosis is Prophase. The first and longest phase of mitosis is prophase. During prophase, chromatin condenses into chromosomes, and the nuclear envelope breaks down. In animal cells, the centrioles near the nucleus begin to separate and move to opposite poles of the cell.

[#880] Chlorosis is
Correct Answer

(B) The yellowing of leaves due to the loss of chlorophyll

Explanation

Solution: Chlorosis is the yellowing of leaves due to the loss of chlorophyll. Chlorosis is a yellowing of leaf tissue due to a lack of chlorophyll. Possible causes of chlorosis include poor drainage, damaged roots, compacted roots, high alkalinity, and nutrient deficiencies in the plant. Affected leaves turn yellow, except for the veins, which remain green. In severe cases, foliage may turn brown and die.