Class 12th Biology 2017 Set1 Outside Delhi Board Paper Solution
Question 24
(a) When a seed of an orange is squeezed, many embryos, instead of one are observed. Explain how it is possible.
(b) Are these embryos genetically similar or different ? Comment.
Answer
(a) It is due to polyembryony. Occurrence of more than one embryos in a seed is called as POLYEMBRYONY. In orange, the nucellar cells, synergid or integument cells develops into a number of embryos of different sizes. eg : - Citrus.
(b) In such embryos parental characters are maintained hence they are genetically similar. In this process, there is no segregation of characters in the offspring (progeny).
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