Work And Energy — Science STD 9 — Question

Which of the following organisms has cell wall?

When the cell is small, then____________________?

Actively dividing cells are present in:

The mean radius of the earth's orbit round the sun is 1.5 × 10¹¹. The mean radius of the orbit of mercury round the sun is 6 × 10¹⁰ m. The mercury will rotate around the sun in:

An organism made up of many cells is known as:

Evaporation that occurs directly from the solid phase below the melting point is called as:

Xylem is made of:

1. Tracheids
2. Vessels
3. Both of these
4. None of these

Which of the following does not possess the ability to do work not because motion?

1. A sparrow flying in the sky.
2. A sparrow moving slowly on the ground.
3. A sparrow in the nest on a tree.
4. A squiral going up a tree.

In Whittaker’s classification, unicellular organisms are grouped under:

1. Protista.
2. Porifera.
3. Fungi.
4. Protozoa.

Most of the alpha particles go straight through the foil if it is passed through a thin metal foil. This is due to the reason that: