P-1 Carbon Compounds — Science STD 10 — Question

The germ cell A produced by a person X is round in shape and it fuses with another germ cell B having a long tail and produced by a person Y. The fusion of A and B produces a new cell C. The cell C divides repeatedly and grows inside the organ D of person X to form E in which the body features of the unborn baby are not much developed. E grows further to form F in which the various body features of the unborn baby (like hands, legs, head, eyes, and ears, etc.) can be identified. F grows further and ultimately forms a baby. What are A, B, C, D, E and F? Out of the two persons X and Y, which one is male and which one female?

Sketch, labell and classify: Earthworm

Write a note on Salam Mumbai Foundation.

The surface of water in a lake appears green due to a layer of tiny free-floating organisms X on its surface. The lake water also contains organisms like water beetle, fish and tadpole. The sun shines over the lake water and provides energy for the functioning of this lake ecosystem.

1. What could organisms X be?
2. Write a food chain comprising of all the four organisms mentioned.
3. What is the general name of the food chains like the one written above?
4. Name (i) secondary consumer (ii) producer (iii) tertiary consumer, and (iv) primary consumer, in the above food chain.
5. If the tertiary consumer gets 0.2 J of energy from the secondary consumer, then how much energy was radiated by the sun to the producer?

Recognize the following food chain Describe the ecosystem to which it belongs.
Grasshopper → snake → Paddy field → Eagle → Frog.

How can we offer first aid to victims of any disaster?

Explain the working of an astronomical telescope using refraction of light.

Write short note: Coelom.

Draw a neat labelled diagram: Electrolytic reduction of alumina.