Question

Assertion: In leptosporangiate development, sporangia are formed from a group of initials.
Reason: Eusporangiate development of sporangia starts from a single initial.
A. In both the assertion and the reason are true but the reason is a correct explanation of
the assertion.
B. In both the assertion and the reason are true but the reason is not a correct explanation
of the assertion.
C. If the assertion is true but the reason is false.
D. If both the assertion and reason are false.

Answer 1

Sporangia are structures that are involved in spore production. They are classified based on the developmental pattern i.e., from a group of initials or a single initial. A single initial can result in the formation of infinite spores whereas many initial cells produce many spores.

Complete answer:
In the case of a leptosporangiate type of development, a small sporangium develops from a single initial. They produce a small, definite number of spores. This type of sporangium occurs in the sorus and it is covered by a flap of tissue known as indusium. Whereas in the case of a eusporangiate type of development, a large sporangium develops from the group of initials. It helps in developing the whole sporangium, its contents, and stalk. It produces many spores, and sometimes fuse to form synangia. In leptosporangiate development, a single surface cell initiates the sporangium by division. Then after some divisions, stalk, spores, and a thin wall is formed around the sporangium.

Hence, the correct option D, i.e., If both the assertion and reason are false.

Note: A group of initial cells develops into a eusporangium and this type of development is known as eusporangiate whereas a single initial cell develops into a leptosporangium and this type of
development is known as eusporangiate. Eusporangiate development is found in all the vascular
plants and leptosporangiate development is found in some pteridophytes.