ISC (Science) ISC Class 12 - CISCE Important Questions

Give one significant difference between primary lymphoid organs and secondary lymphoid organs. Give one example of each.

A substance that stimulates the production of antibodies is called ______.

Briefly explain the role of the following in providing defence against infection in the human body:

B-cells

Briefly explain the role of the following in providing defence against infection in the human body:

T-cells

What are the vestigial organs?

Give any one example of a vestigial organ in human body.

If a person shows the production of interferons in his body, then he is suffering from ______.

Assertion: Lymphocytes originate and proliferate in primary lymphoid organs.

Reason: Spleen is a secondary lymphoid organ.

Observe the relation between the first two words and then fill in the fourth word.

Histamine: Mast cells :: Antibody: ______.

Expand the abbreviation MALT.

Mention one significant difference between Parenchyma and Sclerenchyma.

Mention one significant difference between Symplastic movement and apoplastic movement

In the following questions/statements has four suggested answers. Rewrite the correct answer

Roots and shoots lengthen through the activity of:

(A) Apical meristem

(B) Vascular Cambium

(C) Lateral meristem

(D) Cork Cambium

In the following questions/statements has four suggested answers. Rewrite the correct answer

Opening and closing of stomata is due to:

(A) Ca²⁺

(B) Na⁺

(C) K⁺

(D) Cl–

Give three anatomical differences between a monocot root and a dicot root

Explain the transpiration pull theory for an ascent of sap

Why are xylem and phloem classified as complex tissues?

Describe the structure of phloem.

Describe the ultra-structure of a chloroplast.

What is single cell protein?