Genetics And Plant Breeding - Study Mode

[#666] Seed multiplication ratio of rapeseed red gram, hybrid maize, sorghum and jute is
Correct Answer

(A) 1 : 100

Explanation

Solution: The seed multiplication ratio of rapeseed red gram, hybrid maize, sorghum and jute is 1 : 100. The seed Replacement Ratio is a measure of how much of the total cropped area was sown with certified seeds in comparison to farm-saved seeds. The process of seed planning involves the use of the Seed Multiplication Ratio (SMR) in the computation and estimation of seed demand in the country.

[#667] Which component of immune response is crippled in AIDS
Correct Answer

(C) Helper T-cells

Explanation

Solution: Helper T-cells are the component of the immune response that is crippled in AIDS. HIV can destroy CD4 cells by direct virus cytotoxicity and indirectly through the host response against HIV-infected cells or gp120-targeted cells. Cells of the macrophage lineage are generally not destroyed but serve as a reservoir of the virus. HIV also causes functional impairment in T cells, B cells and monocytes.

[#668] Histone Proteins are synthesized during
Correct Answer

(C) S

Explanation

Solution: Histone Proteins are synthesized during the S phase. The S phase (Synthesis Phase) is the phase of the cell cycle in which DNA is replicated, occurring between the G 1 phase and G 2 phase. S-phase entry also regulates histone production at the RNA level. Instead of poly adenylated tails, canonical histone transcripts possess a conserved 3 stem-loop motif that selectively binds to Stem Loop Binding Protein (SLBP). During S-phase, the accumulation of SLBP acts together with NPAT to drastically increase the efficiency of histone production.

[#669] Match the following columns: Column I (Crop) Column II (Centre of origin) a. Barley 1. South America b. Potato 2. Abssynia c. Chick-pea 3. China d. Soybean 4. Mediterranean
Correct Answer

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

Explanation

Solution: a. Barley originated from Abyssinia. Abyssinia is believed as the centre of origin for barley by one group and south East Asia (China, Tibet, Nepal) by another group. b. Potato originated from South America. The humble potato was domesticated in the South American Andes some 8,000 years ago and was only brought to Europe in the mid-1500s, from where it spread west and northwards, back to the Americas. c. Chick Pea originated from the Mediterranean region. Chickpeas then spread to the Mediterranean region around 6000 BC, and India around 3000 BC. d. Soy Bean originated in China. The origin of soybean cultivation remains scientifically debated. The closest living relative of the soybean is Glycine soja, a legume native to central China.

[#670] Antibiotic that cause mis-incorporation of amino acids in protein synthesis is
Correct Answer

(C) Puromycin

Explanation

Solution: An antibiotic that causes the misincorporation of amino acids in protein synthesis is Puromycin. Puromycin is a naturally occurring aminonucleoside antibiotic that inhibits protein synthesis by ribosome-catalyzed incorporation into the C-terminus of elongating nascent chains, blocking further extension and resulting in premature termination of translation.