Natural Resources — Science STD 9 — Question

__________ is the practice of growing a series of different types of crops in the same area in subsequent seasons:

Which of the following plant group bears naked seeds?

1. Pteridophyta.
2. Bryophyta.
3. Gymnospermae.
4. Angiospermae.

The functional activities of a cell are controlled and directed by the:

Organelle other than nucleus, containing DNA is:

Unicellular microscopic organisms were first studied by _____________.

The technique of growing two or more different crops together in the same field is known as:

Which of the following is incorrect pair?

Cell wall of plant cells is chiefly composed of:

The skin is devoid of scales in:

1. Cartilaginous fish.
2. Bony fishes.
3. Reptiles.
4. Amphibians.

Alikunhi is famous for development of the technique of:

1. Hypophysation
2. Composite fish culture.
3. Mariculture
4. Shell culture.