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Biology 12 Past Paper 2023 | Notely

HomePast papersBiology 122023

All Biology 12 papers

Class 12 · Past paper

Biology 12 past paper 2023

38 published questions in this index. The full practice view lets you work through them and track your own attempts.

14 MCQs24 written questionsPractise this paper

Question index

1
A snail was moving on a table. When the table was tapped, the snail stopped moving. When tapping was done repeatedly, the snail stopped responding to it. Identify the type of behav…
MCQ1 marksannual
1
Compare the mechanism of osmoregulation in marine and freshwater animals.
Part B3 marksannual
1
Describe stages of the Menstrual Cycle in Human Female. Also draw the diagram outline.
Part C7 marksannual
2
Due to lightning, a forest was set on fire and destroyed. The type of succession which will occur then is termed as:

This is a skimmable index, not a replacement for the study surface. Open the practice view to answer questions and use the linked study material.

MCQ1 marksannual

2

How are 'Counter Current Multiplier' mechanism and 'hormones' involved in concentrating urine?

Part B3 marksannual

2

Explain **Latent Learning** with example.

Part C6 marksannual

3

Which one is a steroid hormone?

MCQ1 marksannual

3

Write the names and functions of hormones produced by **Thyroid Gland**. Write about the problems related with abnormal secretion of hormones in different stages.

Part C7 marksannual

4

Enlist the cells associated with bones. Also write their respective functions.

Part B3 marksannual

4

Explain events of Gastrulation in Human. Also draw the diagram.

Part C6 marksannual

5

Differentiate between two types of Neurotransmitters. Also give one example of each.

Part B3 marksannual

5

Describe the mechanism of DNA Analysis using Restriction Fragment Length Polymorphism (RFLP).

Part C7 marksannual

6

The workers in a honey bee hive exhibit:

MCQ1 marksannual

6

Limbic system lies under cerebrum. Write down its parts and their functions.

Part B3 marksannual

6

How is **Carbon Dioxide** transported through blood as **Bicarbonate ions**? Explain in detail.

Part C6 marksannual

7

A man and a woman with blood groups A and B respectively have four children all with different blood groups of the ABO system. By a cross show genotypes of both parents and offspri…

Part B3 marksannual

8

Which one of the following is **NOT** a Sexually Transmitted Disease?

MCQ1 marksannual

8

$XO-XX$ is a pattern of sex determination. Explain with example.

Part B3 marksannual

9

The extra embryonic membrane which provides a fluid filled environment for developing fetus is:

MCQ1 marksannual

9

Write about the causes and symptoms of Phenylketonuria.

Part B3 marksannual

10

In pea plant, round and wrinkled seed shape is controlled by $R$ and $r$ alleles respectively. The cross which will give rise to a 1:1 ratio of both phenotypes can be:

MCQ1 marksannual

11

Baldness is more common in males than in females because it is a:

MCQ1 marksannual

11

Briefly explain any three characteristics of **Genetic Code**.

Part B3 marksannual

12

In DNA replication, the primer:

MCQ1 marksannual

12

What is **Speciation**? Briefly explain **Sympatric Speciation**?

Part B3 marksannual

13

After successful implantation of blastocyst into endometrium of uterus, level of which hormone increases?

MCQ1 marksannual

13

What is **Divergent Evolution**? Explain with a suitable example.

Part B3 marksannual

14

Normally vaccination can be done at any age for:

MCQ1 marksannual

14

How does the **Endosymbiont hypothesis** explain the evolution of Eukaryotes from Prokaryotes?

Part B3 marksannual

15

According to Hardy Weinberg Theorem, which one of the following factor cannot change allelic frequency?

MCQ1 marksannual

15

Populations have many characteristics. Write about any three characteristics.

Part B3 marksannual

16

Restriction endonucleases can be used in Genetic Engineering to:

MCQ1 marksannual

16

Enlist the sources of Chlorofluorocarbons (CFCs). How do they cause Ozone Depletion?

Part B3 marksannual

17

In Nitrogen cycle, conversion of Nitrates into nitrogen is termed as:

MCQ1 marksannual

17

a. What is the role of **CFTR gene** in a normal person? b. Write down symptoms of **Cystic Fibrosis**. c. Write mechanism of **Gene Therapy** used to cure Cystic Fibrosis.

Part B3 marksannual

18

Elaborate the role of **Microbes** in **Food Processing** by giving any three examples.

Part B3 marksannual

19

Write about two major techniques of animal cell culture.

Part B3 marksannual

20

What are **Acclimatization** and **Selection**? How do they help to improve crops?

Part B3 marksannual