SEXUAL REPRODUCTION IN FLOWERING PLANTS
1. (a) Reeja a science student observed the structure of mature embryo sac comprising antipodals, central cells and egg apparatus. Explain each one of them. (Scores: 1+2+1=4)
(b) Three different ﬂowers are given to you in the practical class.
(i) Maize (ii) Vallisneria (iii) Rose
You are asked to group them based on pollinating agents. Describe the adaptations of each ﬂower related with the agents of pollination. (Scores:1+1+1+1=4)
1. The chromosome number of onion is = 16 (2n). Find the chromosome number in the following cells with reasons.
a. Endosperm cells b. Zygote (Scores: 1+1 =2)
2. You are supplied with three different flowers such as Maize, Vallisneria and Rose and they have different pollinating agents also.
a. Differentiate the type of pollination.
b. Write their various adaptability in the plants suited to pollination. (Scores: 1+3=4)
1. In some seeds the nucellus may be persistent. Such nucellus is called
(a) Endosperm (b) Scutellum
(b) Plumule (d) Perisperm (score : 1)
2. What is a false fruit? Cite an example. (Scores: 2)
3. A unisexual flower having no androecium is called
a) Dithecous (b) Dioecious
b) Monoecious (d) Pistillate (Scores : 1)
1. The development of pollen grains in Angiosperms is called
a. Microsporogenesis S b. Embryogenesis
c. Megasporogenesis d. Gametogenesis (Score: 1)
2. Which of the following part in a ﬂower is haploid?
a. Anther wall b. Pollen mother cell
c. Synergid d. Secondary nucleus (Score 1)
3. The hard outer layer of pollen is composed of
a. Exine b. Intine c. Integument d. Sporopollenin (Score 1)
4. Observe the following diagram and label A, B, C & D. (Scores: 2)
1. When the pollen is transferred from anther to the stigma of the same ﬂower, the pollination is called autogamy.
(a) Cleistogamous ﬂowers are invariably autogamous. Explain. (Score: 1)
(b) Geitonogamy is functionally cross pollination, but genetically similar to autogamy. Justify the statement. (Score: 1)
2. The thick protective covering of the fruit is known as ………………… (Score: 1)
1. Synergids have a special cellular thickening at micropylar tip. Write the name of name and function of the structure.
2. In angiosperms, female gametophyte is known as embryo sac. Explain its development.