The World of Metals and Non-metals — Science STD 7 — Question

What are the main requirements of photosynthesis?

Which metal is liquid at room temperature?

Name some countries having tropical rain forest.

Does Cuscuta (Amrbel) have chlorophyll? How does it prepare its food?

Paheli observed that most of the fish in the pond of her village were gradually dying. She also observed that the waste of a factory in their village is flowing into the pond which probably caused the fish to die. If the factory waste is acidic in nature, how can it be neutralised?

What is digestion?

Which part of the digestive canal is involved in:
Killing of bacteria _____________.

Fill in the blanks. Sweat contains water and ________.

At what temperature water evaporates?

Name the vein in the body that carries oxygen-rich blood.