Tag: basis of classification in animals
Questions Related to basis of classification in animals
Cryopreservation is carried out at
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-10 to -20$^{0}$C
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-50 to -60$^{0}$C
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-196$^{0}$C
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-100$^{0}$C
Virus-free clones are obtained from
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Callus
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Embryoids
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Haploid culture
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Shoot tip culture
Shoot tip culture is the culture of terminal part of shoot to a plant in in-vitro condition or in lab called as shoot tip culture. Mostly the shoot tip culture used for obtain disease free plant without genetically changes. The plant which affected by any contaminant mostly by viruses have saved by shoot tip culture, because shoot tip of any affected plant is less or free from contamination (viruses, bacteria, fungus).
Dwarf variety of wheat was developed by
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M.S. Swaminathan
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Vavilov
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Borlaug
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Both A and C
Norman Borlaug developed a special breed of dwarf wheat that resisted a wide spectrum of plant pests and diseases and produced two to three times more grain than the traditional varieties. During the period from 1949-55, M S Swaminathan undertook research on potato, wheat, rice and jute genetics, after which he worked on Mexican dwarf wheat varieties.
The concept of "Centres of Origin of Cultivated Plants" was put forward by
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Swaminathan
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Mendel
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Vavilov
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Borlaug
Vavilov worked on global genetic diversity of cultivated plants throughout his life, from which he developed several major theories that have played an important role in the development of botany, genetics and plant breeding. One such theory among several is "Theory of centres of origin of cultivated plants" (1920).
Genomic DNA library is
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Packing of donor DNA in a collection of vectors.
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A collection of gene vectors.
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Collection of organisms for extracting DNA.
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A collection of literature about DNA.
A genomic library is a collection of total genomic DNA from a single organism. This DNA is packed in a population of identical vectors for storage. Each vector contains a different insert of DNA.
Gene library consists of
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All fragments of a genome
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Frozen germplasm
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Tissue culture
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Living bacteria having clones of genes
A gene library can be defined as a collection of living bacteria colonies that have been transformed with different pieces of DNA from the organism. These DNA fragments are the sources of the genes of interest.
Genetic erosion is
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Deforestation
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Shifting cultivation
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Adopting genetically uniform varieties
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All of the above
Genetic erosion is a process, whereby an already limited gene pool of an endangered species of plant or animal diminishes even more when individuals from the surviving population die off without getting a chance to meet and breed with others in their endangered low population. The term is sometimes used in a narrow sense, such as when describing the loss of particular alleles or genes, as well as being used more broadly, as when referring to the loss of varieties or even whole species.
Genetic erosion occurs because each individual organism has many unique genes which get lost when it dies without getting a chance to breed. Low genetic diversity in a population of wild animals and plants leads to a further diminishing gene pool inbreeding and a weakening immune system can then "fast track" that species towards eventual extinction.
Vavilov collected............. varieties of Wheat
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26,000
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2,600
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4,600
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260
Vavilov collected not less than 26,000 varieties of wheat alone, were kept in cultivation at Leningrad. These collections formed the basis for new theories on the origin of cultivated plants and laid the foundation for the future improvement of crop plants and of one of the largest and oldest seed banks in the world today.
Which one will be best for germplasm collection?
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Britain
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France
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Portugal
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Peru
Germplasm is a term used to describe living genetic resources such as seeds or tissue, maintained for the purpose of breeding, preservation, and other research uses. These resources may take the form of seed collections stored in seed banks, trees growing in nurseries, animal breeding lines maintained in animal breeding programs or gene banks, etc. Germplasm collections can range from collections of wild species to elite, domesticated breeding lines that have undergone extensive human selection.
Holstein-Friesian (HF) gene bank collections were established in France to conserve genetic diversity for this breed. The cryobanks have captured substantial amounts of genetic diversity for the HF compared with the current populations. A substantial part of the US, French, and Dutch collections seems to be genetically similar. On the other hand, the US collection in particular represents an interesting reservoir of HF genes of the past. Gene banks can play an important role in conserving genetic diversity within livestock breeds over time, and may support industry in the future when needed.
Dwarfing gene of wheat is
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Pal - 1
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Atomita - 1
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Norin - 10
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Pelita - 2
The Rht - B1b and Rht - D1b are dwarfing genes, derived from Norin - 10. Norin - 10, which was a semi - dwarf variety bred in Japan and released in 1935. Norin - 10 was used in order to improve lodging resistance in winter wheat.