Tag: basis of the classification of animals
Questions Related to basis of the classification of animals
Cleidoic egg is found in
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Birds
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Reptiles
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Insects
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Both A and B
Cleidoic eggs have a protective shell, and are laid out of water. The shell is porous to air, and may be flexible or calcareous (hard). The eggs contain all the food the embryo needs to develop into a hatchling. The significance of the cleidoic egg is that it enables reproduction out of, and often away from, water. It is a characteristic of birds and reptiles. Hence, option D is correct.
The presence of gill slits, in the embryos of all vertebrates support the theory of?
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Metamorphosis
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Biogenesis
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Organic evolution
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Recapitulation
The evolution of this structure lead to the human lineage.
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Bone
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Cranium
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Jaws
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Notochord
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Vertebrae
The notochord is the defining structure forming in all chordate embryos. In humans beings, the notochord is formed in the third week and eventually replaced by the vertebral column.
A collection of cloned DNA fragments that represents the entire genome is called genomic library.
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True
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False
A genomic library is a collection of the total genomic DNA from a single organism. The DNA is stored in a population of identical vectors, each containing a different insert of DNA
Valuable plant materials likely to become irretrievably lost in the wild or cultivation are kept preserved in viable conditions in
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Gene library
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Gene pools
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Gene banks
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Bio-reserves
Gene banks are a type of biorepository, which preserve genetic material. For plants, this could be by freezing cuttings from the plant, or stocking the seeds (e.g., in a seed bank). For animals, this is the freezing of sperm and eggs in zoological freezers until further need. With corals, fragments are taken which are stored in water tanks under controlled conditions.
Plant genetic material in a 'gene bank' is preserved at $-196^0$C in liquid nitrogen as mature seed (dry).
'Biosphere reserve' is an example of
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In vivo conservation
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Ex situ conservation
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In situ conservation
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All of the above
A biosphere reserve is an ecosystem with plants and animals of unusual scientific and natural interest. It is a title given by UNESCO to help protect the sites. The plan is to promote management, research and education in ecosystem conservation. This includes the 'sustainable use of natural resources'.
In situ conservation is on-site conservation or the conservation of genetic resources in natural populations of plant or animal species, such as forest genetic resources in natural populations of tree species.
The loss of the sum total and variety of all the genes and their alleles present in a population or species is called as
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Genetic conservation
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Genetic erosion
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Species extinction
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Gene pooling
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.
Genetic erosion occurs because each individual organism has many unique genes, which get lost when it dies without getting a chance to breed.
Germplasm is
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Obsolete and improved genetic material
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Genetic material of related wild type
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Both a and b
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Improved genetic material
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.
Greatest genetic diversity is found in areas where
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Plants grow wild
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Crops are cultivated
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Species originated
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Production is the highest
Genetic diversity refers to the variety of genes within a species. Each species is made up of individuals that have their own particular genetic composition. Within a species there may also be discrete populations with distinctive genes. Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook was the first to coin the term 'speciation' for the splitting of lineages or "cladogenesis," as opposed to "anagenesis" or "phyletic evolution" occurring within lineages.
More diversity will be introduced to gene pool when speciation occurs; as a result of which more and more species will be produced.
The species used as natural genetic engineer is
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Agrobacterium tumefaciens
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Bacillus thuringiensis
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Aspergillus
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Drosophila
Agrobacterium tumefaciens will transfer genes (T-DNA region of Ti plasmid) into the plant that produces its food or nutrient called opines (opines are not needed for plants). Apart from that, it also integrates genes for cell division and proliferation leading to crown gall disease, so that more number of cells result in more production of opines. Because of this reason it is called as a 'natural genetic engineer'.