Science (English Medium) Class 11 - CBSE Question Bank Solutions for Biology

Nitrogen fixation is shown by prokaryotes and not by eukaryotes. Comment.

Name a plant which lacks chlorophyll. How will it obtain nutrition?

A farmer adds Azotobacter culture to soil before sowing maize. Which mineral element is being replenished?

What is the function of leghaemoglobin in the root nodule of a legume?

Name one non-symbiotic nitrogen fixing prokaryote.

Rice fields produce an important greenhouse gas. Name it.

Complete the equation for reductive amination

\[\ce{->[?] + NH^{+}4 + NADPH ->[][?] glutamate + NADP + H2O}\]

Name the most crucial enzyme found in root nodules for N₂ fixation? Does it require a special pink coloured pigment for its functioning? Elaborate.

We find that Rhizobium forms nodules on the roots of leguminous plants. Also Frankia another microbe forms nitrogen fixing nodules on the roots of non-leguminous plant Alnus.

1. Can we artificially induce the property of nitrogen fixation in a plant – leguminous or non-leguminous?
2. What kind of relationship is observed between mycorrihiza and pine trees?
3. Is it necessary for a microbe to be in close association with a plant to provide mineral nutrition? Explain with the help of one example.

Trace the events starting from the coming in contact of Rhizobium to a leguminous root till nodule formation. Add a note on importance of leg hemoglobin

Give the biochemical events occurring in the root nodule of a pulse plant. What is the end product? What is its fate?

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?

In tropical rain forests, the canopy is thick and plants growing below receive filtered light. How are they able to carry out photosynthesis?

Why does the rate of photosynthesis decrease at higher temperatures?

Dialysing unit (artificial kidney) contains a fluid which is almost same as plasma except that it has ______.

There are many endocrine glands in human body. Name the glands which is absent in male and the one absent in female.

State whether true or false:

Gastrointestinal tract, kidney and heart also produce hormones.

The figure shows the effect of light on the rate of photosynthesis. Based on the graph, answer the following question:

1. At which point/s (A, B or C) in the curve is light a limiting factor?
2. What could be the limiting factor/s in Region A?
3. What do C and D represent on the curve?

Graph of light intensity on the rate of photosynthesis

List the hormones secreted by the following:

Atrium

List the hormones secreted by the following:

Kidney