Question

apparatus ?
Q.3 Short Answer Questions :
1. How polyembryony can be commercially
exploited ?
2. Pollination and seeds formation are very
crucial for the fruit formation. Justify
the statement.
3. Incompatibility is a natural barrier in the
fusion of gametes. How will you explain
this statement?
4. Describe three devices by which cross
pollination is encouragedinAngiosperms
by avoiding self pollination.​

Answer 1

Answer:

1. Polyembryony can be commercially exploited as disease free plants can be obtained by this method and it also increases the probability of survival under varied conditions.
2. In the case of the angiosperms, the seeds are being inside the fruit whereas in case of the gymnosperms the seeds are exposed that is there is no development of the fruit.The development of fruit takes place due to the post-fertilization development of the ovary into the fruit.The ovule gets transformed into the seeds. As a result of this propagation and pollination is very essential for fruit development.
3. In gametic incompatibility, if the sperm and ova are from different species then they do not recognize each other and hence do not fuse to form the zygote. Hence, incompatibility act as a natural barrier for fusion of gametes to prevent reproduction between individuals of different species.

• Receptivity of stigma and release of the pollen grain is not synchronized, i.e., stigma becomes receptive much before pollens are released or after they are released to avoid self-pollination.

• Self-incompatibility: A genetic method to prevent pollens from fertilizing   ovules of the same flower by inhibiting their germination on stigma or pistil.

• Production of unisexual flowers: So that the male and female parts will be present on different plants i.e., dioecious or on different flowers in the same plant (monoecious). This prevents both autogamy and geitonogamy