Sex cells of both male and female are diploid. They fuse and form tetraploid zygote. This zygote undergoes meiosis, thus forming a diploid zygote. Spirogyra bears haploid plant body forming zygospores after the gametic fusion.
Where does meiosis occur in Spirogyra?
In Ulothrix/Spirogyra reduction division (meiosis) occurs at the time of zygospore formation. Plant body of Ulothrix and Spirogyra, is gametophytic (haploid), they produce zoogametes (n) which fuses to form zygosporic (2n) diploid, which is a resting spore.
Does meiosis occur after zygote formation?
After fertilization, a zygote is formed. In the case of Chlamydomonas, zygospore represents diploid zygote. This zygospore is the only diploid cell in the entire lifecycle. It is thus that same zygospore that later undergoes meiosis to form haploid offspring.
Does meiosis happen after fertilization?
At fertilization, the secondary oocyte completes meiosis II to form a mature oocyte (23,1N) and a second polar body.
Does meiosis occur in meiocyte?
D. Megaspore. Hint: Meiosis takes place only in sexually reproducing organisms. Through this process of meiosis, the diploid meiocyte divides into four genetically different haploid gametes.
Is Spirogyra and Ulothrix same?
Question : Ulothrix and Spirogyra are
Ulothrix and Spirogyra are filamentous and unbranched.
What is the difference between Spirogyra and Ulothrix?
Ulothrix, genus of filamentous green algae found in marine and fresh waters. … For the paramecium to move backward, the Answer Spirogyra is a filamentous alga.
Is meiosis a fertilization?
Whereas somatic cells undergo mitosis to proliferate, the germ cells undergo meiosis to produce haploid gametes (the sperm and the egg). … The development of a new progeny organism is then initiated by the fusion of these gametes at fertilization.
What is the difference between meiosis and fertilization?
Meiosis — How Your Body Makes Sperm or Eggs
Mitosis gives rise to almost all the cells in the body. A different type of cell division called meiosis gives rise to sperm and eggs. During fertilization the sperm and egg unite to form a single cell called the zygote which contains chromosomes from both the sperm and egg.
Does mitosis happen after fertilization?
The zygote undergoes mitosis to form two identical cells that remain attached. This takes place about 36 hours after fertilization. Mitosis then occurs more frequently.