Neural Control and Coordination — BIOLOGY STD 11 Science — Question

Photosynthetic organisms occur at different depths in the ocean. Do they receive qualitatively and quantitatively the same light? How do they adapt to carry out photosynthesis under these conditions?

Discuss the types of enzyme cofactors that are required for the efficient activity of enzymes.

What is excretion? Write any four differences between ammonia and uric acid excretion.

Can there be DNA replication without cell division?

Briefly describe the following: Atherosclerosis.

Neha planned to go the lakeside for picnic with her friends. Suddenly they noticed a man drowning in the lake. Everyone was frightened, but Neha asked them to stop panicking and take the man out of water. After the man was rescued, he was found unconscious. Neha then suggested that mouth to mouth artificial respiration should be given to save the man. One of her friend did as she guided.Finally, the man was saved. He thanked Neha and her friends for their help.

1. Why is artificial respiration given?
2. Can artificial respiration bring back a person to consciousness even after death?
3. What values are shown by Neha?

If a plant shows a symptom which could develop due to deficiency of more than one nutrient, how would you find out experimentally, the real deficient mineral element?

The Rhizobium lives in a symbiotic association with leguminous plants. This kind of relationship teaches us which of the following lessons? What are the benefits of cooperation for humans?

1. We should learn to take benefit from others.
2. Cooperation is always good for mutual benefit.
3. We should always maintain friendly relations with our neighbours.

Give a brief account of structure and functions of Endoplasmic Reticulum.

Explain the following terms:

1. Actinomorphic.
2. Gamosepalous.
3. Syncarpous.