Our Environment — Science STD 10 — Question

The angle of reflection is equal to the angle of incidence :

The clear sky appears blue because :

Pancreatic juice contains enzymes which digest:

While studying saponification reaction, a student measures the temperature of the reaction mixture and also finds its nature using blue/red litmus paper. On the basis of his observations the correct conclusion would be :

Which of the following is the correct path taken by urine in our body?

You are asked by your teacher to study the different part of an embryo of a gram seed. Given below are the steps to be followed for the experiment.

1. Soak the gram seeds in plain water and keep them over might.
2. Cut open a soaked seed and observe its different parts.
3. Take some dry gram seeds in a petri dish.
4. Drain the excess water.
5. Cover the soaked seed with a wet cotton cloth and leave them for a day.

The correct sequence of these steps is :

What provides the energy which then flows through a food chain?

The oxygen liberated during photosynthesis by green plants comes from :

Which one of the following is not a natural ecosystem?

The theory of evolution of species by natural selection was given by: