P-2 Social health — Science STD 10 — Question

Remediation is the process of removing dangerous or poisonous substances from the environment, or limiting the effect that they have on it. When any biological organism is used for remediation, it is called bioremediation. When plant species are used for the purpose of remediation, it is called phytoremediation. When any microbes are used then it is named as microbial remediation. The methods of such remediation have helped to clean the environment from toxic effluents, especially sewage and crude oil. Dr. Anand Chakraborty, a scientist of Indian origin, has worked on Pseudomonas aeruginosa which have reduced the crude oil films into carbon dioxide and water.
1.What is the meaning of remediation?
2.What is the difference between phytoremediation and microbial remediation?
3.Which environmental pollutant is mainly removed through bioremediation processes?
4.What is the role of Pseudomonas aeruginosa?
5.Why Dr. Anand Chakraborty’s work phenomenal?

Explain the mechanism of photosynthesis.

A filamentous alga X is found in ponds, lakes and slow-moving streams. The filament of this alga simply breaks into two (or more) pieces on maturing and each piece then grows to become a complete new alga.

1. Name an alga which X is likely to be.
2. What is the colour of X?
3. What is the method of forming new algae by the breaking of parent alga known as?
4. An Amoeba also breaks up to form two daughter Amoebae. What is the difference in the splitting of Amoeba and splitting of this alga as a method of reproduction?
5. Name one marine animal which reproduces in the same way as alga X.

Express the magnification produced by a lens in terms of the focal length of the lens and (1) the object distance (2) the image distance.

Name the following diagrams and explain the concept behind them.
1. Fleming’s right hand rule:
2. Fleming’s left hand rule:

Write short notes on the following: Galvanizing.

 A calorimeter has mass 100 g and specific heat 0.1 kcal/kg ·°C. It contains 250 g of liquid at 30 °C having specific heat of 0.4 kcal/kg·°C. If we drop a piece of ice of mass 10 g at 0 °C into the liquid, what will be the temperature of the mixture?

The white solid compound A decomposes quite rapidly on heating in the presence of a black substance X to form a solid compound B and a gas C. When an aqueous solution of compound B is reacted with silver nitrate solution, then a white precipitate of silver chloride is obtained along with potassium nitrate solution. Gas C does not burn itself but helps burn other things.

1. What is compound A?
2. What is compound B?
3. What is gas C?
4. What do you think is the black substance X? What is its function?
5. What is the general name of substances like X?

Sketch, labell and classify: Planaria

What is menstrual cycle? Describe it in brief.