## Book Store

Currently only available for.
CBSE Gujarat Board Haryana Board

## Previous Year Papers

Download the PDF Question Papers Free for off line practice and view the Solutions online.
Currently only available for.
Class 10 Class 12
Give the role of minerals.

Role of minerals :

1. The mineral elements are absolutely necessary for supporting normal growth and reproduction.

2.  The minerals are components of protoplasm. The elements having variable valency bring oxidation and reduction reactions e.g. Fe, Cu.

3. K+ ions help in the opening and closing of stomata.

4. Salts of weak acids and weak bases act as buffers.

5. Minerals maintain osmotic potential of cell sap and permeability of plasmalemma.

6. Minerals also act as cofactors and thus bring catalytic reactions.

7. K+ and boron help in transportation of food in the phloem tissue.

135 Views

Name the best known symbiotic nitrogen fixing bacterium.

Rhizobium.
638 Views

Which pigment is present in the root nodules of legumes ?

Leghaemoglobin.
985 Views

How is nitrogenase enzyme protected ?

The nitrogenase enzyme is very sensitive to the molecular oxygen. It requires anaerobic conditions to work. The leg-haemoglobin in the nodule acts as an oxygen scavenger just meainting the anaerobic condition needed by the enzyme.
684 Views

What is Hidden hunger in the case of plants?

Hidden hunger refers to a situation in which a crop needs more of a given nutrient yet has shown no deficiency symptoms. The nutrient content is above the deficiency symptom zone but still considerably needed for optimum crop production
510 Views

What type of condition is created by leghaemoglobin in the root modules of legumes ?

Anaerobic.
777 Views