Question

The life cycle of flowering plants exhibits the same alternation of generations seen in lower plants (n gametophyteà2n sporophyte; where 2n = diploid number of chromosomes of the species). How does this life cycle compare with that of higher animals?

Answer 1

A life cycle is the sequence of stages an organism goes through from one generation to the next. Organisms that reproduce sexually can have different types of life cycles, such as haploid or diploid life cycle.

Haploid life cycle- This is the simplest life cycle. It is found in many single-celled eukaryotic organisms. An organism with a haploid life cycle spends the majority of their lives as haploid gametes. When the haploid gametes fuse, they form a diploid zygote. It quickly undergoes meiosis to produce more haploid gametes that repeat the life cycle

Diploid life cycle-organisms with a diploid life cycle spend the majority of their lives as diploid adults. when they are ready to reproduce, they undergo meiosis and produce haploid gametes. gametes then unite in fertilization and form a diploid zygote, which immediately enters G1of the cell cycle. next, the zygote's DNA is replicated.finally, the processes of mitosis and cytokinesis produce two genetically identical diploid cells. though repeated rounds of growth and division, this organism becomes a diploid adult and the cycle continues.

the higher animals show a diploid life cycle.

alternation of generation is a type of life cycle that occurs in plants. A multicellular haploid gametophyte with n chromosome alternates with a multicellular diploid sporophyte with 2n chromosomes, made up of n pairs. A mature sporophyte produces haploid spores by meiosis, a process that reduces the number of chromosomes to half, from 2n to n. The haploids spores germinate and grow into a haploid gametophyte. At maturity, the gametophyte produces gametes by mitosis, which doesnot alter the number of chromosomes. Two gamates fuse to produce a dipliod zygote, which developes into a diploid sporophyte. This cycle, from gametophyte to sporophyte is the way in which all land plants and many algea undergo sexual reproduction.