Science (English Medium) इयत्ता ११ - CBSE Question Bank Solutions

Some varieties of wheat are known as spring wheat while others are called winter wheat. Former variety is sown, and planted in spring and is harvested by the end of the same season. However, winter varieties, if planted in spring, fail to flower or produce mature grains within a span of a flowering season. Explain, why?

It is known that some varieties of wheat are sown in autumn but are harvested around next mid summer.

What could be the probable reason for this?

It is known that some varieties of wheat are sown in autumn but are harvested around next mid summer.

What term is used for this promotion of flowering under low temperature?

It is known that some varieties of wheat are sown in autumn but are harvested around next mid summer.

Which plant hormone can replace the cold treatment?

Corpus luteum secretes a hormone called ______.

List the hormones secreted by the following:

Ovary

Write a short note on the functions of the following hormone:

Estrogens

Define the following term:

Superior ovary

Take one flower each of families Fabaceae and Solanaceae and write its semi-technical description. Also, draw their floral diagrams after studying them.

Write the floral formula of an actinomorphic bisexual, hypogynous flower with five united sepals, five free petals. Five free stamens and two united carpals with superior ovary and axile placentation.

Draw illustrations to bring out anatomical difference between Monocot root and dicot root.

What are the conditions necessary for fixation of atmospheric nitrogen by Rhizobium. What is their role in N₂ -fixation?

What are the steps involved in formation of a root nodule?

Look at leaves of the same plant on the shady side and compare it with the leaves on the sunny side. Or, compare the potted plants kept in the sunlight with those in the shade. Which of them has leaves that are darker green? Why?

List the hormones secreted by the following:

G-I Tract.

An association between roots of higher plants and fungi is called ______.

A dikaryon is formed when ______.

With respect to fungal sexual cycle, choose the correct sequence of events ______.

There is a myth that immediately after heavy rains in forest, mushrooms appear in large number and make a very large ring or circle, which may be several metres in diameter. These are called as ‘Fairy rings’. Can you explain this myth of fairy rings in biological terms?

Fungi are cosmopolitan. Write the role of fungi in your daily life.