Electricity — Science STD 10 — Question

What are the three R’s to save the environment? Explain with one example of each.

Draw a labelled diagram of the human male reproductive system. With the help of this diagram, describe the working of human male reproductive system?

How do the interactions take place in the biotic and abiotic factors of ecosystem?

Draw a neat labelled diagram of the human excretory system.

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?

Write short note:  Mock drill.

Draw electron dot structure of cyclohexane

An object placed 4cm in front of a converging lens produces a real image 12cm from the lens.

1. What is the magnification of the image?
2. What is the focal length of the lens?
3. Draw a ray diagram to show the formation of image. Mark clearly F and 2F in the diagram.

P and Q are two types of plants having weak stems which cannot stand upright on their own. The plants P and Q have organs R and S respectively which can grow towards any support which they happen to touch and wind around that support. It is observed that organ R originates from the leaves of the plant whereas organ S originates directly from the stem of the plant.

1. What is (i) R, and (ii) S?
2. What is the name of growth movement exhibited by the organs R and S?
3. Name the stimulus involved in this case.
4. State whether the behaviour of organs R and S is a tropic movement or a nastic movement.
5. Name one plant like P and another plant like Q.