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प्रश्न
Read the following statement and justify the same in your own words with the help of a suitable example.
Geographical and reproductive isolation of organisms gradually leads to speciation.
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उत्तर
- Every species survives in specific geographical conditions and has particular requirements for food and habitat.
- The reproductive ability and breeding period of different species are also different.
- Because of these differences, individuals of one species cannot reproduce with individuals of another species.
- When populations are separated by distance or geographical barriers, they are called geographically isolated, and when they cannot interbreed, they are called reproductively isolated.
- Although subspecies may have the same ancestors, long-term isolation leads to genetic variation, which results in the formation of new species called speciation.
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संबंधित प्रश्न
Struggle between cow and cow to get grass is called ______.
What is meant by speciation?
Will geographical isolation be a major factor in the speciation of a self-pollinating plant species? Why or why not?
"Natural selection and speciation leads to evolution." Justify this statement.
Name one reptile in given case where higher incubation temperature leads to the development of :male progeny.
Which of the following may be used to obtain an F2 generation?
(a) allowing flowers on a parent plant to be self-pollinated
(b) allowing flowers on an F1 plant to be self-pollinated
(c) cross-pollinating an F1 plant with a parent plant
(d) cross-pollinating two parent plants
In peas, a pure tall plant (TT) is crossed with a pure short plant (tt). The ratio of pure tall plants to pure short plants in F2 generation will be ______.
Name five varieties of vegetables which have been produced from 'wild cabbage' by the process of artificial selection.
Fill in the following blank with suitable word:
Broccoli has evolved from .............. by the process of artificial selection.
What is meant by a species?
Give two examples of plant species and two of animals.
How are those species which are now 'extinct' studied?
The theory of evolution of species by natural selection was given by ______
Which of the following statement is incorrect with respect to variations?
(a) all variations in a species have equal chance of survival
(b) change in genetic composition results in variations
(c) selection of variations by environmental factors forms the basis of evolutionary process
(d) variations are the minimum in asexual reproduction
According to the evolutionary theory, the formation of a new species is generally due to ______
Define speciation according to A.E. Emerson.
In human males, all the chromosomes are paired perfectly except one. These unpaired chromosomes are ______
(i) Large chromosome
(ii) Small chromosome
(iii) Y chromosome
(iv) X chromosome
Add a note on allopatric speciation.
