In both species repeated pairing of a CS and US eventually produces a CR in response to the CS alone. In the sea-slug this is a very direct process, in the species we have been discussing in these lectures - rats, dogs, humans and so on - I hope you have seen that it is far from being so simple.
Answer:
DNA plays a very significant role in the field of forensic science. During any criminal investigation, the DNA can reveal the prime guilt or the innocence of a person. The smaller pieces of evidence collected from the crime scene is sufficient for finding out the hint regarding a criminal.
Some of the evidence from which the DNA of a particular person can be identified includes the hair with the roots, tooth with the pulp, bones with bone marrow.
DNA study can also aid in establishing the identity of a missing person, both dead and buried remains. Moreover, the analysis of DNA evidence can help in clarifying paternity and maternity disputes.
Following enlisted are the answers for the above mentioned question.
Explanation:
1. Population pyramids is graphical representation of data which enables oneself to distinguish and have a clear picture in minds about the ratio of population densities keeping any one parameter as constant. Population pyramids could be used to analyze data in many different scales on the basis of gender,age groups, race etc. Examples-having a record of no. of individuals in different age groups in India.
2. Generally, there are 3 types of population pyramid on the basis of shapes of the pyramid. Those are;
- Expansive
- Constrictive
- Stable
Siting an example of age-sex pyramids,
In case of the Expansive, population pyramids show that the populations that have a larger number of persons in young age groups. The shape obtained hence is usually with high fertility rates with lower death rates
Then comes, Constrictive population pyramids. These are named so since they are constricted at the bottom. They undue a low percent of young people as compared with other age groups. These type of pyramids show decreasing birth rates.
And at last, Stationary also called as stable population pyramids are the ones which depicts almost equal proportion of the population in each of the all age groups. There is not a decrease or increase in population; it is stable.