Improvement in Food Resources — Science STD 9 — Question

What is chemical characteristics of funeal cell wall.

Give one example of an Indian and foreign poultry breed which when crossed produce an improved variety. List any one desirable trait expected from such cross breeding.

How are diseases transmitted in crops?

Name the device or machines which convert: Electrical energy into heat energy.

Name the quantitity, the slope of whose graph gives:
Acceleration.

Classify epithelial tissues on the basis of arrangements of layers.

Define green manure. Give one example.

Which of the two produces ultrasonic waves: porpoise or whale?

“The properties of the product are different from those of the constituents”. State whether this statement best describes an element, a compound or a mixture.

Which of the following symbols of elements are incorrect? Give their correct symbols.
Sodium So