Advertisements
Advertisements
प्रश्न
Read the following statement and justify same in your own words with the help of suitable example.
Geographical and reproductive isolation of organisms gradually leads to speciation.
Advertisements
उत्तर
- Every species survives in specific geographical conditions. The requirements of food and habitat are specific for each species. Their reproductive ability and period is also different.
- Therefore, the individuals from one species cannot reproduce with individuals from other species.
- When they are separated by distance or geographical barriers, they are said to be geographically isolated.
- When they cannot reproduce with each other, they are said to be isolated reproductively.
- The ancestral species of both subspecies may be the same, but due to long-term isolation, there is genetic variation between the two. Therefore, the isolation leads to speciation.
APPEARS IN
संबंधित प्रश्न
List three main factors responsible for the speciation and briefly describe each one of them
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.
List four factors responsible for speciation.
Name one reptile in given case where higher incubation temperature leads to the development of female progeny.
The palisade cells of a species of plant contain 28 chromosomes. How many chromosomes will there be in each gamete produced by the plant?
(a) 56
(b) 28
(c) 14
(d) 4
Select the group which shares the maximum number of common characters.
Fill in the following blank with suitable word:
Broccoli has evolved from .............. by the process of artificial selection.
Give an example of characteristics being used to determine how close two species are in evolutionary terms.
With the help of an example, explain how variation leads to evolution.
What is meant by a species?
The theory of evolution of species by natural selection was given by ______
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
The theory of evolution of species by natural selection was given by
Cichlid fishes in Lake Victoria are representatives of ______ type of speciation.
Add a note on allopatric speciation.
Add a note on sympatric speciation.
Arrange the major events as per geological time scale:
(Origin of conifers, Abundance of trilobites, Diversification of fishes, All types of marine algae, Formation of Forests, Rise of dinosaurs, Extinction of seed ferns, Rise of modern insects.)
| Geological time period |
Major events | |
| 1. | Cambrian | ______ |
| 2. | Devonian | ______ |
| 3. | Permian | ______ |
| 4. | Triassic | ______ |
