Question

what is cromosome? states its any two typical features? Describe chromosomal basis of sex determination in humans

Answer 1

chromosomes are thread like structures in the nucleusof a cell formed by DNA which carries genes. the determination of a sex in humans is depend on the males gamete dominant part of X is dominant then baby girl will born and if Y will be dominant then baby boy will born all this determination is done by gene which is present in chromosome

Answer 2

Hi friend,

Chromosomes are the thread like thread like structure present in the nucleus of a cell.It contains genes which has genetic material called DNA(Dioxy Ribo Nuclie Acid) which transfer heridatory information from one generation to another.The number of chromosomes are fixed for a particular species we have 46 chromosomes in 23 pairs.Chromosomes can be seen rod like only when the cell is to divide else they are always seen as an entangled mass of thread like structures.

As we got to know that human beings have 46 chromosomes in 23 pair.The first 22 pairs are called as autosomes the 23rd pair is called as sex chromosome as it helps in sex determination.In females 23rd pair is XX.In males it's XY.The gametes in females(ovum) are always formed with an X chromosome but gametes in males(sperms) are formed with X chromosome or Y chromosome.At the time of fertilization if a sperm carrying X chromosome fertilizes the egg then the new born will be a girl and if sperm carrying Y chromosome fertilizes the egg then the new born will be a boy.

In simple words and signs-:

XX-Girl
XY-Boy

Hope it helped you............................