12th Standard CBSE Syllabus & Materials

12th Standard CBSE

CBSE 12th Economics Government Budget and the Economy Previous year Question Papers Study Material - QB365 Set A

NEW

12th Standard CBSE

CBSE 12th Computer Science Interface Python with MySQL - New Previous year Question Papers Study Material - QB365 Set A

NEW

12th Standard CBSE

CBSE 12th Computer Science Database Concept - New Previous year Question Papers Study Material - QB365 Set A

NEW

12th Standard CBSE

CBSE 12th Computer Science Data Communication - New Previous year Question Papers Study Material - QB365 Set A

NEW

12th Standard CBSE

CBSE 12th Computer Science Data Structures - New Previous year Question Papers Study Material - QB365 Set A

NEW

12th Standard CBSE

CBSE 12th Computer Science Functions - New Previous year Question Papers Study Material - QB365 Set A

CBSE 12th Standard Biology Subject Evolution Case Study Questions With Solution 2021

Published on: 21/05/2021

QB365 Provides the updated CASE Study Questions for Class 12 Biology, and also provide the detail solution for each and every case study questions . Case study questions are latest updated question pattern from NCERT, QB365 will helps to get more marks in Exams

Download CBSE Class 12th Standard CBSE Biology question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 12th Standard CBSE Biology

Questions + Answers key

Take MCQ Biology Test

QB365 Student Learing Managemnet System

Std: 12th Standard CBSE - Biology

chapter: - Case study Questions

Visit QB365-SLMS - https://www.qb365.in/slms/ Complete Questions and Answers

Questions:

Case Study Questions

3 x 4 = 12

In 1950s, there were hardly any mosquitoes in Delhi. The use of the pesticide, DDT on standing water
killed their larvae. But, now there are mosquitoes because they have evolved DDT-resistance through the interaction of mutation and Natural selection. State in a sequences, how that could have happened.

The forelimbs of four vertebrates are shown in the diagram shown above.
(a) What type of evolution is exhibited by the similarity among these organs in those organisms?
(b) What are such organs known as?
(c) What do they indicate?

(a) State the hypothesis which S.L. Miller tried to prove in the laboratory with the help of the set up given above.
(b) Name the organic compound observed by him in the liquid water after running the above experiment.
(c) A scientist simulated a similar set up and added CH₄, NH₃ and water vapour at 800°C.
Which important component is missing in his experiment?

Visit QB365-SLMS - https://www.qb365.in/slms/

Answers Key:

Case Study Questions

3 x 4 = 12

(i) There were some larvae with a mutated gene that conferred resistance to DDT.
(ii) The DDT-resistant larvae survived while the others died.
(iii) The DDT-resistant larvae reached adulthood and reproduced in large numbers.
(iv) The progeny also consisted mostly ofDDT-resistant larvae.
(v) Natural selection operating over a number of generations, favoured the DDT-resistant mosquitoes to reproduce in large numbers.
(vi) Hence, today there is a large number of mosquitoes that are resistant to DDT.

(a) Divergent evolution.
(b) Homologous organs.
(c) Homology indicates common ancestry.

(a) S.L. Miller tried to prove the hypothesis of Oparin and Haldane; it is as follows:
(i) The first from oflife could have come from the pre-existing non-living organic molecules like RNA, proteins, etc.
(ii) Formation oflife was preceded by chemical evolution that resulted in the formation of diverse organic molecules from inorganic constituents.
(b) Amino acids.
(c) Hydrogen is missing.