2006-07-20 22:57:45 · 10 answers · asked by nagendra r 1 in Science & Mathematics ➔ Zoology
The XX/XY sex-determination system is one of the most familiar sex-determination systems and is found in human beings and most other mammals. In the XY sex-determination system, females have two of the same kind of sex chromosome (XX), while males have two distinct sex chromosomes (XY). Some species (including humans) have a gene SRY on the Y chromosome that determines maleness; others (such as the fruit fly) use the presence of two X chromosomes to determine femaleness.
Sex Chromosomes X-Y
The male gametes or sperm cells in humans and other mammals are heterogametic and contain one of two types of sex chromosomes. They are either X or Y. The female gametes or eggs however, contain only the X sex chromosome and are homogametic. The sperm cell determines the sex of an individual in this case. If a sperm cell containing an X chromosome fertilizes an egg, the resulting zygote will be XX or female. If the sperm cell contains a Y chromosome, then the resulting zygote will be XY or male.
2006-07-20 23:08:02 · answer #1 · answered by cranura 4 · 0⤊ 0⤋
Chromosomes do not participate in reproduction per se. It is just that the sperm and the ovum will have a single set of chromosomes instead of two. In reproduction, these chromosomes merely recombine during crossing-over. All the chromosomes present in a sperm and an ovum (which are basically the same as those present in other cells) "participate" in reproduction.
2006-07-21 06:25:22 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Each normal cells in the human body has 46 chromosomes.
When an egg and a sperm are made the "parent" cells divide. Each egg and sperm cell have only half the chromosomes of the normal human cell.
When the egg is fertilized by a sperm the resulting cell has 46 chromosomes 23 from the mother and 23 from the father.
2006-07-20 23:12:26 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Your Q is very good. Most of the answers are close to correct one. But I feel will not satisfy your curiosity.
You say each cell have sex chromosome.
So one thing you might be aware that Somatic cells do not participate in sexual reproduction. Only sex cells participate through gamete formation.
Then your curiosity may be........
What is the role of sex chromosomes in each cell?
The answer is.....
Chromosomes are structures appear for cell division only. The actual functional part is Gene or DNA.
A zygote cell has all genes in function. When developments proceeds......specialisation of cells occur for the formation of tissues and organs. And at that time inactivation of unwanted genes occur. For example genes of Pancreas gland will have active genes for Pancreatic hormones and for general cell metabolism and not for Pituitary or ovarian hormones which are synthesised by the specialised cells of these organs.
There sex chromosomes of other somatic cells are not as active as of sex cells of gonads (testes and ovary)
I hope your answer is here. Keep on questioning wish you all the best and GOOD LUCK
2006-07-24 21:12:19 · answer #4 · answered by Dr. Homo sapiens 2 · 0⤊ 0⤋
sex Chromosomes The nuclei of human cells include 22 autosomes and a couple of sex chromosomes. In females, the sex chromosomes are both X chromosomes. adult males have one X chromosome and one Y chromosome. The presence of the Y chromosome is decisive for unleashing the developmental software that leads to a toddler boy.
2016-12-02 01:12:31 · answer #5 · answered by ? 3 · 0⤊ 0⤋
The sperm cell and egg cell contain 23 pairs each, when they fuse it's called a zygote and cell division occurs by mitosis forming an embryo
2006-07-20 23:02:37 · answer #6 · answered by pixellizedness 2 · 0⤊ 0⤋
before fusion gamets are formed with just one set of chromosome, so they take part in reproduction
2006-07-21 01:28:03 · answer #7 · answered by yahooo 2 · 0⤊ 0⤋
chromosomes of : sperms n ova participate in repro
2006-07-20 23:01:51 · answer #8 · answered by dromyl 3 · 0⤊ 0⤋
there is a certain ammount of chromosones in your cells. they are in pairs in which its twin is slightly different. in a gamete- sperm or egg- ther is only one set . there are many different combos. and thats why you are different than your siblings. out of each new ste there is a predominant chromo. and this is where you get you looks, hereditary illness, and inherited quirks.
2006-07-21 01:05:40 · answer #9 · answered by Anonymous · 0⤊ 0⤋
IN THE LONG RUN, THEY ALL HAVE A PART IN
REPRODUCTION BUT THE CHROMOSONES
THAT ACTUALLY PARTICIPATE IN IT ARE THE GAMETES.
SPERM AND EGG.
2006-07-20 23:02:15 · answer #10 · answered by Anonymous · 0⤊ 0⤋