Drow the diagram of a micrrosporangium and label its wall layers. Write briefly on the role of the endothecium.

Assertion : A typical microsporangium of angiosperms is generally surrounded by four wall layers - epidermis, endothecium, middle layers and tepetum. Reason : The outer three wall layers perform the function of protection and help in dehiscence of anther to release the pollen.

Which of the following statements regarding the structure of microsporagium are correct ? (i) Microsporangium is generally surrounded by four wall layers-epidermis, endothecium, middle layers and tapetum (ii) outer three layers perform functions of protection and dehiscence of anthers. (iii) Cells of tapetum undergo meiosis and produce micropore tetrads.

Draw a neat and labelled diagram of sperm and state the significance of anatomical structure of its head piece.

With a neat, labelled diagram, describe the part of a mature angiosperm embryo sac. Mention the role of Synergids.

Name the embryonic stage that gets implanted in the uterine wall of the human female. Also draw its diagram.