CBSE Class 12 Biology NCERT Exemplar Solutions: Chapter 7, Evolution
To help students access the accurate solutions to all NCERT Exemplar problems of class 12 Biology, our experts have solved all the questions in detail but simple language.
Here we are providing the NCERT Exemplar solutions for CBSE Class 12 Biology chapter 7, Evolution. All these solutions have been prepared by the subject experts and have been revised to bring the accurate study material for our students. These solutions have been collated in the form of PDF which students can download for free of cost and refer the same when required.
Few problems along with their solutions from this chapter are given follows:
Q. The theory of spontaneous generation stated that
(a) life arose from living forms only
(b) life can arise from both living and non-living
(c) life can arise from non-living things only
(d) life arises spontaneously, neither from living nor from the non-living.
Ans. (c) life can arise from non-living things only
The theory of spontaneous generation stated that an obsolete theory that states that living organisms can originate from inanimate (non-living) objects. It is also known as abiogenesis.
Q. Variations during mutations of meiotic recombinations are
(a) random and directionless
(b) random and directional
(c) random and small
(d) random, small and directional
Ans. (a) random and directionless
Variations during mutations of meiotic recombination are random and directionless. Hugo de Vries based on his work on evening primrose stated that it is mutation which causes sudden appearance of variations that results in speciation.
He stated that mutations are sudden, heritable and persistent in successive generation. He contradicted Darwinian variations that are small and directional.
Q. What is founder effect?
Ans.Sometimes, a small number of individuals become isolated from a larger population to form a new population at some distance away from their place of origin.The gene pool of the new population differs from the source population. It is possible that the change in allele frequency is so drastically different in the new sample that they become a different species. The original driftted population becomes founders and this effect is called founder effect.
Q. Enumerate three most characteristic criteria for designating a Mendelian population.
Ans. Three most characteristic criteria for designating a Mendelian population are
(i) Population must be sufficiently large.
(ii) Population must have potentialities for free flow of genetic material among individuals, through sexual reproduction,
(iii) Migration should either be nil or negligible.
Find below the links to download Class 12 Biology NCERT Exemplar Solutions for chapter 7 - Evolution:
Link to Download PDF
Multiple Choice Questions
Very Short answer type questions
Short answer type questions
Long answer types questions
Class 12 Biology NCERT Exemplar Problems:
The NCERT Exemplar problems are considered to be the most applicative kind of problems which help to enhance a student’s critical thinking and problem solving ability. These problems form the best practice source to prepare effectively for board exams and the medical entrance tests. So, it’s very important for students to practice the NCERT exemplar problems to prepare well for the boards and the competitive exams.
Main topics discussed in Class 12 Biology, Chapter 7- Evolution, are:
- Origin of life
- Evolution of life forms - a theory
- What are the evidences for evolution?
- Adaptive radiation
- Biological evolution
- Mechanism of evolution
- Hardy - Weinberg principle
- A brief account of evolution
- Origin and evolution of man
Download the complete NCERT Exemplar book from the following link:
Note: Once you are done with all the NCERT Exemplar problems, refer the solutions given above in this article to check the correctness of your own solutions and know the right way to get the perfect answers.