Question

Beginning with the process of pollination, describe how plant reproduction occurs. Be sure to include in your discussion the role of the pollen tube, double fertilization, and the endosperm.

Answer 1

ANS- Plant reproduction--->Its the process of producing new offsprings from parental plants, by the fusion of male (pollen)and female gamete(ovum).it is the asexual mode of reproduction because it involves two parental gametes for producing the offspring.

• The offspring are genetically different from the parent's plants because of the sexual mode of reproduction, which allows the recombination of DNA.

STEPS OF PLANT REPRODUCTION

STEP 1- Pollen grain is released from the male flower organ called anther and attaches a female organ called the stigma of female flower plant this process is called pollination.

STEP 2- pollen grain that attached to stigma activates some signaling due to that the pollen grain travels through the tube-like structure called pollen tube and reached to the egg and resulted in fertilizing the egg and endosperm by fusing with.

STEP 3-After fertilization the fertilized egg now grow and converted into a mature seed which is then sown into the soil and converted into new plant have multiple numbers of flowers having thousand of female and male gametes.

Pollen tube--->It is the tubular structure produce in male gametophyte it can travels from stigma to egg(ovules ) located down to the stigma in flower in order to fertilize the egg in female gamete.

Double fertilization--->It is the process through which 2 male pollen grain attach to the stigma and enters into a pollen tube and from two of them 1 fertilizes with the egg to form a zygote and the other one fertilizes with the 2 polar nuclei in order to form the endosperm that's why it is called double fertilization because 2 fertilization events occur here. endosperm production is necessary because it provides the food to growing seed in the form of oil and protein by covering them.