Board exams are considered to be of high importance as these exams signify your academic achievements and give a boost to pursue your favorite career path. Therefore, students should practice hard to score high marks in their board exams.
Solving previous years’ board question papers is a perfect practice to give an edge to your board exam preparations. It helps you to acquaint with important questions and the conceptual topics from which questions are frequently asked in exams. It also lets you analyse your weak and strong areas so that you may amend your preparations accordingly.
In this article, we are providing the Rajasthan Board Class 12 Biology Solved Question Paper 2018. All the solutions provided here are explained in a way to help students easily understand the concepts/theories used thus making the exam preparations easy and effective.
Key features of Rajasthan Board Class 12 Biology Solved Question Paper 2018 are
- Simple and easy solutions are provided for the questions
- Appropriate concepts/theories have been used in solutions
- Neat and clean diagrams are used wherever required
Rajasthan Board Class 12 Biology Question Paper and its solution can be downloaded in the form of PDF.
Structure of Rajasthan Board Class 12 Biology Paper 2018 is as per the following table:
| Part |
Question Nos. |
Marks Per Question |
| A |
1 – 13 |
1 |
| B |
14 – 24 |
2 |
| C |
25 – 27 |
3 |
| D |
28 – 30 |
4 |
Question number 14, 27, 28, 29 and 30 have internal choices.
A few sample questions and their solutions are given below:
Q. What is point Mutation?
Ans.
Point mutation is a change in a single base pair of DNA by substitution, deletion, or insertion of a single nitrogenous base.
Q. What will be effect on embryonic development if Placenta does not form after implantation. Explain.
Ans.
Placenta acts as a life support system for the developing fetus. It supplies blood and nutrition to the fetus. It also protects the fetus from harmful bacteria and infections. Problems with the placenta can affect the developing baby's growth. The baby cannot grow and develop normally in the womb if it does not get enough oxygen and nutrients. This increases the chances of complications during pregnancy and delivery.
Q. 18. Describe the Miller’s experiment related to origin of life.
Ans.
The Miller’s experiment was a chemical experiment that simulated the conditions thought at the time to be present on the early Earth, and tested the chemical origin of life under those conditions. He created electric discharge in a closed flask containing CH4, H2, NH3 and water vapour at 800oC. He observed formation of amino acids. In similar experiments others observed, formation of sugars, nitrogen bases, pigment and fats. Analysis of meteorite content also revealed similar compounds indicating that similar processes are occurring elsewhere in space. The first noncellular forms of life could have originated 3 billion years back. They would have been giant molecules (RNA, Protein, Polysaccharides, etc.).
Q. Explain Commensalism and Mutualism with example.
Ans.
Commensalism: It is a type of relationship where one of the organisms benefits greatly from the symbiosis. The other is not helped but is not harmed or damaged from the relationship. In other words, this is a one-sided symbiotic relationship.
Example: The relationship between cattle egrets and cattle. The cattle egret will eat insects that have been disturbed when the cattle forage.
Mutualism: Mutualism is a symbiotic relationship in which both species benefit.
Example: Relationship between fungi and the roots of higher plants. The fungi help the plant in the absorption of essential nutrients from the soil while the plant in turn provides the fungi with energy-yielding carbohydrates.
To download the completely solved paper, click on the following link:
| Rajasthan Board Class 12 Biology Solved Question Paper 2018 |
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