Give the scientific terms for the following:
1. The transfer of pollen grains from the anther of one flower to the stigma of another flower of the same plant.
2. The entry of pollen tube into the ovule through the micropyle.
3. The type of endosperm formed when each division of the primary endosperm nucleus is followed by cytokinesis.
4. The thin and papery cotyledon, usually a characteristic of monocots.
5. One of the most resistant substances known in the living world that forms the exine layer of the pollen grain.
Find out the number of meiotic divisions to be undergone by the spore mother cells in order to produce:
(i) 800 microspores
(ii) 160 megaspores
Arrange the following stages involved in the development of a dicot embryo in the correct sequence:
Proembryo, heart-shaped embryo, globular embryo, zygote, mature embryo.
How do cleistogamous flowers differ from the chasmogamous flowers? Explain with examples.
Briefly explain the various ways through which the pollen tube may enter into the ovule to fertilise the egg.
Define the following terms:
1. Triple fusion
5. Seed dormancy
State whether the following statements are true or false.
1. Cross pollination requires abiotic and biotic agents.
2. Only meiotic divisions are involved in asexual reproduction.
3. Microspores and megaspores are diploid.
4. In most angiosperms, a haploid female gametophyte usually containing 8 nuclei is present within the megasporangium.
5. Development of female gametophyte in most angiosperms is bisporic.
What is the objective of pollination? How would you classify the types of pollination based on the source of pollen?
List down any four functions of Tapetum.
Match the columns A and B.
1. Female gametophyte
2. Male gametophyte
b. Micropylar end
c. Embryo sac
4. Antipodal cells
d. Pollen grain
5. Egg apparatus
e. Chalazal end
Explain the various outbreeding devices witnessed in plants.
Briefly explain what is meant my double fertilisation?
What is the fate of the following parts post-fertilisation?
Why does endosperm formation precedes embryo formation in most of the angiosperms?
How are true fruits, false fruits and parthenocarpic fruits different from each other?
What is meant by polyembryony? Give one suitable example.
Draw a well labelled diagram of a longitudinal section through an anatropous ovule.
Briefly describe how artificial hybridisation can be achieved in a crop improvement programme.
List down the various adaptations seen in an anemophilous flower. Also, mention the names of any two plants in which pollination is achieved by this means.
With the help of a diagram, depict the organisation of a 7-celled-8-nucleated embryo sac.