Genetics And Plant Breeding MCQ Question and Answer | Agriculture MCQ Question

Synaptonemal complex is composed of a dense central element, two relatively dense lateral elements and two relatively less dense transverse elements.
The synaptonemal complex (SC) is a protein structure that forms between homologous chromosomes (two pairs of sister chromatids) during meiosis and is thought to mediate synapsis and recombination during meiosis I in eukaryotes.
The synaptonemal complex is a tripartite structure consisting of two parallel lateral regions and a central element.

The components of a synthetic variety consist of several Open pollinated varieties.
A synthetic variety is developed by intercrossing several genotypes of known superior combining ability i.e., genotypes that are known to give superior hybrid performance when crossed in all combinations.
Synthetic variety is a variety that is developed by inter-mating in all possible combinations of several inbred lines with good general combining ability and mixing their seeds equally whereas composite variety is a variety that is developed by mixing the seed of various genotypes.

In India, the gene bank of wheat is located at Karnal, Haryana.
Gene banks are a type of biorepository that preserves genetic material. For plants, this is done by in vitro storage, freezing cuttings from the plant, or stocking the seeds.
The main intention of genebanks is to conserve collections of plant genetic resources for posterity.

The recommended concentration of EMS for induced mutagensis is 0.03 to 1.5%.
Ethyl methanesulfonate (EMS) is a mutagenic, teratogenic, and carcinogenic organic compound with formula C₃H₈SO₃. It produces random mutations in genetic material by nucleotide substitution; particularly through G:C to A:T transitions induced by guanine alkylation. EMS typically produces only point mutations.
EMS can induce mutations at a rate of 5 × 10^-4 to 5 × 10^-2 per gene without substantial killing.

The Lampbrush chromosome is found in Diplotene.
Lampbrush chromosomes are a special form of chromosome found in the growing oocytes (immature eggs) of most animals, except mammals. They were first described by Walther Flemming and Ruckert in 1882.
Chromosomes transform into the lampbrush form during the diplotene stage of meiotic prophase I due to the active transcription of many genes.

When the anther and stigmas of bisexual flowers mature at the same time is known as Homogamy.
Homogamy refers to the maturation of male and female reproductive organs (of plants) at the same time, which is also known as simultaneous or synchronous hermaphrodism and is the antonym of dichogamy.

Bulbosum Technique' is used in barley for the production of Haploids.
Hordeum bulbosum, bulbous barley, is a species of barley. Since 1970 it has been used in the bulbosum Method to produce doubled haploid wheat and barley plants by crossing it with T. aestivum or H. vulgare, followed by the elimination of the H. bulbosum chromosomes from the offspring.
H. bulbosum is also being looked at as a source of genes for disease resistance and other traits for barley crop improvement.

Cell-to-cell adhesion depends upon Ca²⁺ and Mg²⁺ of the middle lamella.
Cell adhesion is the process by which cells interact and attach to neighboring cells through specialized molecules of the cell surface.
This family of CAMs is membrane proteins that mediate cell-cell adhesion through its extracellular domains and require extracellular Ca²⁺ ions to function correctly.
Cadherins form a homophilic attachment between themselves, which results in cells of a similar type sticking together and can lead to selective cell adhesion, allowing vertebrate cells to assemble into organized tissues.

The cross of an inbred line with an open pollinated variety is known as the Top cross.
Top cross- means the first generation of a cross between an open-pollinated variety and an inbred line, a foundation backcross, or a foundation single cross.
In the top cross, crosses are made between inbreds and either a tester or an open-pollinated variety. This is also known as an inbred-variety cross.

The number of chromosomes in the wheat endosperm is 63.
The endosperm is a tissue produced inside the seeds of most the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species. Wheat has 21 pairs of chromosomes, as the endosperm is triploid.
Thus, it will be 21 × 3 = 63.