The Fundamental Unit of Life — Science STD 9 — Question

Which of the following factors are responsible for the change in state of solid carbon dioxide when kept exposed to air?

1. Increase in pressure
2. Increase in temperature
3. Decrease in pressure
4. Decrease in temperature

1. (i) and (ii)
2. (i) and (iii)
3. (ii) and (iii)
4. (ii) and (iv)

Phylum mollusca can be distinguished from other nonchordates by the presence of:

1. Bilateral symmetry and exoskeleton.
2. A mantle and gills.
3. Shell and non-segmented body.
4. A mantle and a non-segmented body.

Deflection back of a few particles by large angle on hitting thin foil of gold in Rutherford's experiment showed that :

Plant length is increased by:

Plants can be made disease-resistant by:

1. Heat treatment.
2. Hormone treatment.
3. Volchicine treatment.
4. Breeding with their wild relatives.

Pulses are rich in:

Rhythmic contraction and relaxation throughout life, are shown by:

Which of the following has an irregular or variable shape?

1. Euglena
2. Paramecium
3. Amoeba
4. Acetabularia

In the Pila, the gastropod mollusk, the organ of the locomotion is:

1. Mantle.
2. Foot.
3. Tentacles.
4. Legs.

A protozoan disease is:

1. Sleeping sickness.
2. Kala-azar.
3. Malaria.
4. All the above.