what is meiosis? what is haploid and diploid cells and what does half number and full n.o of chromosomes mean? Please explain each and every single concept........i have paper tomorrow.
Answers
Answered by
3
see dear
suppose an organism has diploid no. of chromosomes that means '2n'. if it undergoes meiosis then it's chromosome no. will be reduce to half that is 'n'.
now compare this to humans.we have 46 chromosomes.we are diploid organism. that means our '2n' is 46. and we know that the gametes formed by humans are sperms and ovum
now suppose a sperm and an ovum fuses to form a zygote and that zygote gives rise to a human being (let's call him x). now x should also have 46 chromosome.
if the sperm carrying 46 chromosome and the ovum also carrying 46 chromosome fuses together then the resulting zygote will have 192 chromosomes.
THAT IS NOT THE DESIRED RESULT.
so to produce a zygote having 46 chromosome, the sperm and the ovumust have 23 chromosomes each.
how can a diploid organism produce haploid gametes ??
the answer is by meiosis.
so diploid organism produce haploid gametes by meiosis and then when fertilization occur a diploid organism is formed.
here I would like to mention that meiosis completes in two steps
1 reduction division
2 equational division (which is similar to mitosis)
Some organisms are haploid. no.of chromosomes in them is n .they produce gametes by mitosis
hope this helps
if you have not understood yet, feel free to ask me. if you find it helpful please mark it as brainliest.
suppose an organism has diploid no. of chromosomes that means '2n'. if it undergoes meiosis then it's chromosome no. will be reduce to half that is 'n'.
now compare this to humans.we have 46 chromosomes.we are diploid organism. that means our '2n' is 46. and we know that the gametes formed by humans are sperms and ovum
now suppose a sperm and an ovum fuses to form a zygote and that zygote gives rise to a human being (let's call him x). now x should also have 46 chromosome.
if the sperm carrying 46 chromosome and the ovum also carrying 46 chromosome fuses together then the resulting zygote will have 192 chromosomes.
THAT IS NOT THE DESIRED RESULT.
so to produce a zygote having 46 chromosome, the sperm and the ovumust have 23 chromosomes each.
how can a diploid organism produce haploid gametes ??
the answer is by meiosis.
so diploid organism produce haploid gametes by meiosis and then when fertilization occur a diploid organism is formed.
here I would like to mention that meiosis completes in two steps
1 reduction division
2 equational division (which is similar to mitosis)
Some organisms are haploid. no.of chromosomes in them is n .they produce gametes by mitosis
hope this helps
if you have not understood yet, feel free to ask me. if you find it helpful please mark it as brainliest.
Answered by
1
Meiosis is a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells. The process results in four daughter cells that are haploid, which means they contain half the number of chromosomes of the diploid parent cell.
Similar questions