Question

Read the statement and answer the questions that follow.  (5)

A flower of brinjal has 520 ovules in its ovary. However, it produces a fruit with only 480 viable seeds.

(a) What could have prevented the rest of the 40 ovules from maturing into viable seeds? Explain giving a reason.

(b) Describe the development of a dicot embryo in a viable seed.

(c) Why certain angiospermic seed albuminous while others are exalbuminous? Explain.
 
OR

(a) Name the hormones secreted and write their functions :

(i) by corpus luteum and placenta (any two).

(ii) during Follicular phase and parturition.


(b) Name the stages in a human female where :

(i) Corpus luteum and placenta co-exist.

(ii) Corpus luteum temporarily ceases to exist. 

CBSE Class XII Biology Question Paper 2017

Answer 1

Heya!

(a) The thing that could have prevented the rest of the 40 ovules from maturing into viable seeds can be The damage of the embryo or May be high temperature.

(b) When some certain amount of endosperm are formed then the Formation of endosperms takes place. Pro-embryo is formed by the mitotic division. In dicot plants, 2 cotyledons and an Embryonal axis is there. The portion of embryonal axis below the level of attachment of cotyledon is the hypocotyl, it becomes radicle.Further it forms PEN and finally development takes place.

(c) (Pls. dun delete it Moderators.)