ISC (Science) ISC Class 12 - CISCE Question Bank Solutions

In a karyotype analysis, X and Y chromosomes represent sex chromosomes.

Name the scientist who discovered the X chromosome.

Consider the following information and answer the question that follows:

Make a single pedigree chart using the above information to show the pattern of inheritance of phenylketonuria (PKU) in the family of Reshma.

Describe the ultra-structure of a chloroplast.

What is single cell protein?

Choose the correct option of the following question:

The pressure of the cell contents on the cell wall is known as:

What is a single cell protein? How is it significant for human welfare?

Expand the following abbreviation: SSBP

Give four adaptations in flowers pollinated by insects.

Give a reason for each the following: 

Climax stage is achieved quickly in secondary succession as compared to primary succession.

What is adaptive radiation?

All types of ecological succession whether on land or in water always reaches ______.

Briefly describe the process of spermatogenesis.

1. Which one of the two cities needs a sewage treatment plant?
2. Briefly discuss the steps involved in the treatment of sewage.
3. What will be the effect of sewage treatment on the value of BOD?

The diagram given below shows the various steps in spermatogenesis.

1. Name the parts labelled '1', '2' and '3'.
2. Name the process by which part '3' changes to part '4'.

Name and define the three types of natural selection.

The largest unit in which gene flow is possible is :

(1) Organism

(2) Population

(3) Species

(4) Genes

State any four measures to control noise pollution.

List any three drawbacks of Darwinism.

Explain the evolution of the long neck of giraffe according to Charles Darwin. 

Answer the following question:

Why do Green plants start evolving CO₂ instead of O₂, at high temperatures?