3. PARTHENOGENESIS
Reproduction without fertilization is called parthenogenesis. Different types of parthenogenesis
are as follows
I. BASED ON OCCURRENCE
i. Facultative (not compulsory) - e.g. bee.
ii. Obligatory or constant (compulsory) - e.g. stick insect
iii. Cyclic or spordic : alternation of gamic and agamic population, e.g. aphid.
II. BASED ON SEX PRODUCED
i. Arrhenotoky:
Produce male e.g. bee
ii. Thelytoky:
produce female e.g. aphids
iii. Amphitoky or deuterotoky:
produce both male and female e.g. cynipid wasp.
III. BASED ON MEIOSIS
i. Apodictic :
no meiosis occurs
ii. Automictic:
meiosis occurs, but diploidy is maintained
4.POLYEMBRYONY
This form of asexual reproduction involves the production of two or more embryos from one egg
by subdivision. Mostly observed in parasitic insects (e.g. platygaster). Nutrition for a large number
of developing embryo cannot be supplied by the original egg and is acquired from the host's
haemolmph through a specialized enveloping membrane called
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