CBSE Class 12 Biology Board Question Paper 2019 (Set-1)
This is the CBSE Class 12 Biology Board Question Paper from the 2019 Main Exams Abroad (Set-1). The paper comprises 27 questions divided into four sections: Section A (questions 1-5) with one-mark very short answer questions, Section B (questions 6-12) with two-mark short answer type I questions, Section C (questions 13-24) with three-mark short answer type II questions, and Section D (questions 25-27) with five-mark long answer questions. While there is no overall choice, internal choices are provided in some questions across all sections, allowing students to attempt one of the two alternatives. Neat and properly labelled diagrams are required where necessary. Solving this previous year question paper is crucial for students to familiarize themselves with the exam structure, question types, and marking scheme, thereby enhancing their preparation and performance in the board examinations.
Quick info
| Board | CBSE |
|---|---|
| Class | 12 |
| Subject | Biology |
| Session | 2019 |
| Language | English |
| Type | Previous Year Question Paper |
| Exam type | Board Exam |
Paper pattern
The question paper has 27 questions across four sections (A, B, C, D) with varying marks (1, 2, 3, 5). Internal choices are provided in some questions.
Topics covered
Paper topics
- Parturition signals
- Patterns of inheritance
- Hardy-Weinberg principle
- Evolutionary history
- Allergy response
Important topics
- Parturition signals
- Patterns of inheritance
- Hardy-Weinberg principle
- Evolutionary history
- Allergy response
PDF preview
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Question paper text
Biology Question Paper 2019 (Set-1)
General Instructions:
- There are total 27 questions and four sections in the question paper. All questions are compulsory.
- Section A contains questions number 1 to 5, very short answer type questions of one mark each.
- Section B contains questions number 6 to 12, short answer type I questions of two marks each.
- Section C contains questions number 13 to 24, short answer type II questions of three marks each.
- Section D contains question number 25 to 27, long answer type questions of five marks each.
- There is no overall choice in the question paper, however, an internal choice is
provided in two questions of one mark, two questions of two marks, four questions of three marks and all the three questions of five marks. In these questions, an examinee is to attempt any one of the two given alternatives.
- Wherever necessary, the diagram drawn should be neat and properly labelled.
Question 1
State from where do the signals for parturition originate in human females.
SOLUTION:
The signals for parturition in human females originate from the fully developed foetus and the placenta.
Question 2
Name the pattern of inheritance where F<sub>1</sub> phenotype
- resembles only one of the two parents.
- does not resemble either of the two parents and is in between the two.
SOLUTION:
- Complete dominance
Question 3
- Incomplete dominance
According to the Hardy-Weinberg principle, the allele frequency of a population remains constant. How do you interpret the change of frequency of alleles in a population?
OR
Coelacanth was caught in South Africa. State the significance of discovery of Coelacanth in the evolutionary history of vertebrates.
SOLUTION:
If the Hardy-Weinberg equillibrium/genetic equillibrium is disturbed it would result in evolution. In other words, change in frequency of alleles can be interpreted by evolution. Gene flow, genetic drift, mutation etc. are some of the disturbances which may lead to change in allele frequency.
OR
Coelacanth was a fish was caught in south Africa in 1938, which was thought to be extinct. These animals were called lobefins which evolved into first amphibians that lived on both land and water. These are considered to be the ancestors of modern days frogs and salamanders.
Question 4
State the functions of mast cells in allergy response. OR
Frequently asked questions
What is this document?
This is the CBSE Class 12 Biology Previous Year Board Question Paper from the 2019 Main Exams Abroad, Set-1.
What is the structure of the paper?
The paper has 27 questions divided into four sections: Section A (1-mark), Section B (2-marks), Section C (3-marks), and Section D (5-marks), with internal choices provided in some questions.
How does solving previous year papers help?
Solving previous year question papers helps students understand the board exam pattern, question types, and marking scheme, leading to better preparation and improved scores.
What is the total duration and maximum marks for this paper?
The provided text does not explicitly state the total duration or maximum marks for the paper.
Are there any choices available in the questions?
Yes, while there is no overall choice, internal choices are provided in some questions of one, two, three, and five marks.
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