Atoms and Molecules — Science STD 9 — Question

Goitre is caused due to deficiency of disease?

1. Fluorine.
2. Vitamin C.
3. Vitamin A.
4. Iodine.

Of the following components of phloem is non-living:

1. Sieve tubes.
2. Companion cells.
3. Bast fibers.
4. Phloem parenchyma.

The number of valence electrons in a graphite atom is:

When fast moving alpha particles are made to fall on a thin gold foil, most of them go straight through the foil because:

Smooth muscle fibres are:

The majority of the cells cannot be seen directly with our naked eyes because:

The codes for the specific proteins produced by a cell lies in the ________.

The S.I. unit of energy is

Which of the following statement defines hypertonic solution:

Find out the wrong statement from the following:

1. White revolution is meant for increase in milk production.
2. Blue revolution is meant for increase in fish production.
3. Increasing food production without compromising with environment quality is.
4. None of the above.