Tissues — Science STD 9 — Question

How do animals of Porifera differ from animals of Cnidaria?

1. Calculate the mass number of the element.
2. Write its electronic configuration.
3. Find the valency and an atomic number of the element.

1. Name the phenomenon which helps fresh water unicellular organisms (e.g. Amoeba) continuously gain water in their bodies. Also, name the mechanisms by which these organisms throw out excess of water from their bodies.
2. Give at least two examples in plants where similar phenomenon in used to gain water.

Distinguish between Nonchordata and Chordata.

What provisions are made by local authorities for solid waste management ?

What are permanent tissues of the plants? Give their characteristics.

What are differences between the following:

Aves and mammals.

Write main differences between plant and animal cells.

What is lymph? Describe its function.