Genetics And Plant Breeding - Study Mode

[#106] Folded fiber model of chromosome organisation was proposed by
Correct Answer

(C) DuPraw

Explanation

Solution: Folded fiber model of chromosome organisation was proposed by DuPraw. Based on an electron microscopic examination of the chromosome, DUPRAW (1968) proposed a “folded fiber model” of the metaphase chromosome structure. According to this, the fundamental elements of the chromosomes are long DNA-protein fibers with diameters of about 23 nm.

[#107] Double helical structure of DNA was shown by
Correct Answer

(A) Watson and Crick

Explanation

Solution: The double helical structure of DNA was shown by Watson and Crick. The structure of DNA was proposed by James Watson and Francis Crick in 1953, they stated that it is a double helix and twisted-ladder structure of deoxyribonucleic acid (DNA). They marked a milestone in the history of science and gave rise to modern molecular biology, which is largely concerned with understanding how genes control the chemical processes within cells.

[#108] The complete set of chromosome inherited from generation to generation is
Correct Answer

(D) Genome

Explanation

Solution: The complete set of chromosome inherited from generation to generation is Genome. The genome is all the genetic information of an organism. It is the entire set of DNA instructions found in a cell. A genome contains all the information needed for an individual to develop and function. The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as regulatory sequences, and often a substantial fraction of 'junk' DNA with no evident function.

[#109] Test cross ratio in case of duplicate gene action will be
Correct Answer

(D) 3 : 1

Explanation

Solution: Test cross ratio in case of duplicate gene action will be 3 : 1. The test cross is another fundamental tool devised by Gregor Mendel. A test cross is an experimental cross of an individual organism with a dominant phenotype but an unknown genotype and an organism with a homozygous recessive genotype. The phenomenon when either of the genes can provide the wild-type phenotype, this interaction is called duplicate gene action. Thus, the test cross in case of duplicate gene action will give a ratio of 3 : 1.

[#110] Global Gene Bank of Potato is located at
Correct Answer

(C) CIPPeru

Explanation

Solution: Global Gene Bank of Potato is located at CIP Peru. The genebank at the International Potato Center (CIP) in Lima, Peru maintains clonal and seed collections of potato, sweet potato, and Andean roots and tubers (ARTCs). The genebank is maintained as a global public good under the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA).