Question
Question: The ploidy of aleurone layers is A. n B. 2n c. 3n D. 4n...
The ploidy of aleurone layers is
A. n
B. 2n
c. 3n
D. 4n
Solution
The outermost layer is referred to as the aleurone layer of the endosperm. The ploidy of the aleurone is a result of double fertilization of female gametophyte and two male gametes.
Complete Answer:
The protein found in protein granules of maturing seeds and tubers is aleurone. It describes one of the two major cell types of the endosperm, the aleurone layer. The outermost layer of the endosperm is the aleurone layer, followed by the inner starchy endosperm. This layer of cells may be referred as the peripheral endosperm. This layer lies between the pericarp and the hyaline layer of the endosperm. Aleurone cells remain alive at maturity. The ploidy of the aleurone is (3n) because of double fertilization.
Double fertilization is a complex fertilization mechanism found in Angiosperms. In this process, the two male gametes are fused with a female gametophyte, the embryo sac. Thus the ploidy of the aleurone layer is 3n.
The n indicates half the genome which is contained by the female gametophyte and male gamete. In flowering plants, the flowers produce gametes which are haploid generation formed by meiosis and mitosis cell division. The female haploid gamete is called the ovule. It is produced by the ovary of the flower. The male haploid is pollen which is produced by the anther. The pollen lands on a mature stigma of a flower. It grows into a pollen tube down into the flower. The haploid pollen produces sperm by mitosis. It is released for fertilization. After fertilization, the zygote carries two sets of chromosomes so referred as 2n.
After fertilization, the fertilized ovule develops into the seed while the fruit is formed by the tissues of the ovary. Tetraploidy refers to carrying four sets of chromosomes. The potato is an example of a tetraploid organism. It reproduces by asexually or vegetatively.
Thus the correct choice is A as 3n.
Note: Double fertilization involves the joining of a female gametophyte with two male gametes. This process involves the formation of a layer of seeds.