Download App

Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction in Flowering Plants3 Marks
Question
  1. Do all pollen grains remain viable for the same length of time? Support your answer with two suitable examples.
  2. How are pollen grains stored in pollen banks? State the purpose of storing pollen grains in these banks.
✓

Answer

  1. No; the pollen grains of different species remain viable for different periods of time.

e.g. pollen grains of cereals remain viable for less than 30 minutes whereas some members of Rosaceae, Leguminosae and Solanaceae retain the pollen viability for months.

  1. In the pollen banks, pollen grains are stored. In liquid nitrogen (at -196°C). Such stored pollen grains can be used for breeding programmes whenever necessary.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Sexual Reproduction in Flowering Plants→Sexual Reproduction in Flowering Plants — all question types→BIOLOGY STD 12 Science question papers→Rajasthan Board STD 12 Science question papers→Rajasthan Board question paper generator→

Similar questions

Explain the difference between commensalism and mutualism types of interactions, with the help of a suitable example of each.
→
How can education help in building up a socially responsible and reproductively healthy society? (Enumerate the aspects that should be emphasised).
→
How many primary follicles are left in each ovary at puberty?
→
How did an American Company, Eli Lilly use the knowledge of r-DNA technology to produce human insulin?
→
A person is suffering from Ascariasis. Mention the pathogen causing the disease and an organ of the body affected, three symptoms and one mode of transmission of the disease.
→
What is LAB? What is its role in human stomach?
→
Forests provide intangible benefits to us. Explain by taking three different areas, how.
→
Find out the role of microbes in the following and discuss it with your teacher.
(a) single cell protein (SCP)
(b) soil
→
Which layer of uterus undergoes cyclic changes during the menstrual cycle?
→
Following the collision of two trains, a large number of passengers are killed. A majority of them are beyond recognition. Authorities want to hand over the dead to their relatives. Name a modem scientific method and write the procedure that would help in the identification of kinship.
→