Draw a schematic transverse section of a mature anther of an angiosperm. Label its epidermis, middle layers, tapetum, endothecium, sporogenous tissue and the connective.

An anther is a tetragonal structure consisting of four microsporangia located at the corners. Two microsporangia are located in each lobe of the anther. The microsporangia undergo development and become pollen sacs that contain microspores. The transverse section of an angiospermous anther and its parts has been shown below:

When and where do tapetum and synergids develop in flowering plants? Mention their function.

Tapetum is the innermost layer of the anther wall that develops during microsporogenesis in the anther. A typical anther consists of four microsporangia that are surrounded by anther wall. Anther wall consists of the outer epidermis, endothecium, middle layers and innermost tapetum. Its function is to provide nourishment to the developing pollen grains. Synergids develop during megasporogenesis in the ovule (megasporangium) inside the ovary. These are haploid cells that are located at the micropylar end of the embryo sac in the ovule. The embryo sac is formed from a single megaspore that undergoes three mitotic divisions to form 8 nucleated and seven celled structure. Among these, two are synergids. Synergids have the filiform apparatus which help to guide the pollen tube into it.

E M B I B E

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 41

EASY

12th Uttar Pradesh Board

IMPORTANT

Earn 100

Plumule forms which organ during seed germination?

Important Questions on Sexual Reproduction in Flowering Plants

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 42

Why do you think the zygote is dormant for some time in a fertilized ovule?

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 43

You are given castor and bean seeds. Which one of the two would you select to observe the endosperm?

EASY

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 44

Differentiate between Parthenocarpy and Parthenogenesis. Give one example of each.

HARD

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 45

Name the flowering plant which employs 'sexual deceit' to get pollinated by a species of bee. Write how pollination occurs in this flower?

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 46

Wind pollination flowers are not visited by honey bees. Give two reasons.

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 47

Mention the pollinating agent of an inflorescence of small dull coloured flowers with well exposed stamens and large feathery stigma. Give any one characteristic of pollen grains produced by such flowers.

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 48

Write the characteristic features of the anther, pollen and stigma of wind-pollinated flowers.

MEDIUM

12th Uttar Pradesh Board

IMPORTANT

Biology Crash Course (Based on Revised Syllabus-2023)>Chapter 1 - Sexual Reproduction in Flowering Plants>Exercise>Q 49

Mention the differences between anemophilous flower and entomophilous flower.