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

An organism that has acquired a heritable variation as a result of the sudden change in the hereditary material is called a Mutant.
A mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism.
The natural occurrence of genetic mutations is integral to the process of evolution.

a. P₇₀₀ or photosystem I primary donor, is the reaction-center chlorophyll a molecular dimer associated with photosystem I in plants, algae and cyanobacteria.
b. P₆₈₀ or photosystem II primary donor is the reaction-center chlorophyll a molecular dimer associated with photosystem II in plants, algae, and cyanobacteria, and central to oxygenic photosynthesis.
c. The phosphorylation of ADP to form ATP using the energy of sunlight is called photophosphorylation. It occurs in the grana of the chloroplast.
d. Fixation of Carbon dioxide is the process of conversion of inorganic carbon to organic compounds (glucose) by living organisms. It is called as Calvin cycle, a part of the photosynthetic process, which occurs in the stroma of chloroplasts.

Translocation of carbohydrates mostly takes place in the form of Sucrose.
In plants, sucrose is the major transport form for photo-assimilated carbon and is both a source of carbon skeletons and energy for plant organs unable to perform photosynthesis.
As a molecule translocated over distance, sucrose has to pass through several membranes. It is transported around the plant in phloem vessels.

The technique used for determining the molecular mass of a substance by dissolving it and measuring the freezing point of the solution is called Cryoscopy.
Cryoscopy is the measurement of the freezing point of a liquid using a cryoscope. The estimation of the molecular weight of a compound by measuring its effect on the freezing point of a solvent.
Helium is used in cryoscopy to obtain the very low temperatures required for superconductivity.

The jerking is followed in hybrid seed production in Bazra.
Removal of the first tiller or ear of the first tiller for synchronization of flowering of the parental line called Jerking.
Bajra jerking is one of the steps followed for the synchronization of flowering in Bajra. It is done 20 - 25 days after transplanting or 30 - 40 days before direct sowing.

In an F₂ population of the cross, 50% recombinant individuals are observed. Segregation is the main cause of this.
The Principle of Segregation describes how pairs of gene variants are separated into reproductive cells.
The law of segregation ensures that a parent, with two copies of each gene, can pass on either allele. Both alleles will have the same chance of ending up in a zygote. In sexually reproducing organisms, the genome is carried in two identical copies. A copy was inherited from each parent, in the form of a gamete.

Parbhani Kranti' is a Bhindi (Ladyfinger) variety, resistant to YMV (Yellow Mosaic Virus).
Parbhani Kranti, a variety of Okra is produced by mutational breeding and is resistant to the Yellow mosaic virus.
It is Released from MKV, Parbhani in Maharashtra. Fruits are medium-long with tender smooth surfaces at the marketable stage. Fruits have a good keeping quality. The average yield is 8.5 - 11.5 t/ha in 120 days.

In fig the inflorescence is Hypanthodium.
Hypanthodium is a special type of cymose inflorescence. The Hypanthodium inflorescence is found in the genus Ficus of the family Moraceae, e.g., Banyan (Ficus bengalensis), Peepal (Ficus religiosa) and Fig (Ficus carica).
The receptacle in this type of inflorescence becomes spherical, like a hollow sphere with a cavity inside, and it is formed by the fusion of the rachis of the three cymes in the vicinity of each other. These spherical receptacles are like a closed fleshy vessels having a tiny opening at the apex; it opens to the exterior with this opening.

In sugarcane breeding, the initial selection after hybridization is done in the F₁ generation.
The objectives of breeding and selection in plants are the modification of traits and at the same time, to take advantage of the natural genetic variation.
Hybridization in sugarcane is based on the crossing of populations among them, through the technique “plant to plant”, from which F₁ true seed (sexual seed) is obtained.

CO₂ fixation during C₄ pathway occurs in the chloroplast of Bundle sheath cells.
In C₄ cycle of photosynthesis, where a four-carbon compound is produced, unique leaf anatomy allows carbon dioxide to concentrate in 'bundle sheath' cells around Rubisco.
This structure delivers carbon dioxide straight to Rubisco, effectively removing its contact with oxygen and the need for photorespiration.