Some species of ______ and _____ have evolved
a special mechanism t o produce seeds without
fertilisation.
(1) Asteraceae, Brassicaceae
(2) Solanaceae, Grasses
(3) Malvaceae, Asteraceae
(4) Asteraceae, Grasses

also please explain this special mechanism

Dear student,
Please find below the solution to the asked query

The correct option is (4).
Some of the species belonging to the Asteraceae family and some grass species have evolved a special mechanism of seed formation without the fertilisation of ovule by male gamete. This type of seed development without fertilisation is called apomixis. 

The apomictic seeds can develop through following ways :-

1. From diploid egg cell that develops into the embryo without fertilization.
2. From the integuments like diploid nucellar cells surrounding the embryo sac develop into embryo. These cells start dividing and protrude inside embryo sac and develop into embryo.

Hope this information will clear your doubts about the apomixis.
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