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First of all, you're mistaken if you asked yourself this question: XX is the female sex chromosome combination, and XY is male.
It's important to realise that this is the case in humans, but not in all animals. Other animals, for example insects, have different mechanisms for sex determination.
In humans, a fertilised egg cell will divide a few times. Then each cell will turn off all but one of its X chromosomes (the phrasing is because in rare cases a fertilized egg can end up with three or more X chromosomes). This is possible and necessary because one X is sufficient to produce the proteins encoded on it, hence two active X would result in twice the amounts needed.
If you now wondered whether an embryo can also survive and grow to adulthood with only one X and no other sex chromosomes, you are correct. This is called monosomy X and causes a condition known as Turner syndrome.
Any human with only X chromosomes will be female. The Y chromosome, which is much smaller than the X chromosome, carries some additional genes whose influence will set off several mechanisms which ultimately lead to the development as a male instead. A Y chromosome alone cannot sustain life as it does not contain many of the vital genes which are located on the X chromosome.
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always xx represents for female because the x chromosome have such genes which are important foe femaleness while XY always represents male because the y chromosome is responsible for one's maleness because it have such kind of genes which gives maleness to anyone.
EDIT:
your question was why males were XX and females XY. not always are they like that, actually. they aren't supposed to be like that, however during meiosis, if the X chromosome and the Y chromosome in the sperm cells cross over and they cross over more than they are supposed to, the SRY gene that gives males all their sexual organs and makes them different than females, would then be on an X chromosome. if that X chromosome then went into an egg cell (also X) then you would have an XX organism, but because it has the SRY gene on one of the X chromosomes, it would activate making the organism a male rather than female. same thing could happen but the other way, the Y sperm cell could go into the egg, but without the SRY gene, the organism would develop as a female.
Read more: Why_is_xx_a_male_and_xy_a_female
Females have two X chromosomes, and males have one X and one Y. Why are they called "X" or "Y"? A somewhat practical reason, actually- that is their shape.
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Why is it not possible for an individual to have a XY chromosomes?
About half of us DO have an XY chromosome. Males. XX chromosomes are female.
What do the genetic codes xx and xy mean?
There are 22 autosomal chromosomes and 2 sex chromosomes in humans. In all the other chromosomes, the homologous pairs match up genetic loci. However, in human sex chromosomes the X and Y chromosome are different (with the X chromosome being much larger and the Y chromosome carrying genes that cause "maleness"). Someone with an X and a Y chromosome is a male because he has a Y chromosome that carries the genes that code for "maleness". Females "lack" this Y chromosome, and thus show characteristic female phenotypes.
What causes webbed fingers?
Doctors call this condition syndactyly. Webbed fingers or toes can be part of Turner's Syndrome, which is a chromosomal disorder that affects only females. It involves the absence of all or part of one of the sex chromosomes. Normal female chromosomes are expressed as XX. In Turner's Syndrome, the sex chromosomes are expressed as XO, to indicate that there is a chromosome missing. More commonly though, syndactyly is caused by a genetic defect, and is therefore found to run in families. It is found in both males and females who have the normal arrangement of sex chromosomes: XX for females; XY for males. There are five different types of syndactyly which are classified according to which fingers or toes are involved. This condition can be corrected by surgery, which often involves a small skin graft from another part of the body. With the milder types of syndactyly, surgery can be considered elective (that is, not strictly necessary.) However, when fusion of the fingers or toes is extensive, or when the fusion will cause deformity as the fingers and hands grow, surgery is necessary.
How do you enter only diagonal elements in c plus plus?
Matrices have two diagonals: main diagonal and anti-diagonal. The main diagonal runs from top-left to bottom-right. For square matrix A: // main diagonal: for (size_t xy=0; xy<A.size(); ++xy) cin >> A[xy][xy]; // anti-diagonal for (size_t x = A.size()-1, y=0; y<A.size(); --x; ++y cin >> A[x][y];
What is meant by crosswalk when working with databases?
Also referred to as a schema crosswalk, when someone talks about a crosswalk, what they are generally talking about is a table that allows for references to be built that allow the way data is stored in one database to be matched up with data in another database. For instance, let's say a school district's student database software keeps track of the gender of each student with a single character field that codes females with an "F" and males with an "M". The school district is required to upload data about their students to the state in which it operates for analysis, but the state wants to see males coded as "XY" and females coded as "XX". A crosswalk would need to be created that would convert the gender data in the export process. The crosswalk may look something like this: F -- XX M -- XY
What is the difference between males and females in terms of their chromosomes?
Male is XY , female is XX .
What is the difference between the male and female karyotypes?
The main difference between male and female karyotypes is the presence of sex chromosomes. Males typically have one X and one Y chromosome (46, XY), while females have two X chromosomes (46, XX). This difference in sex chromosomes determines the biological sex of an individual.
What is the assigned number of chromosomes in humans?
46 chromosomes or 23 pairs of chromosomes where 44+xx or 44+xy xx are girls xy are boys
Why is it not possible for an individual to have a XY chromosomes?
About half of us DO have an XY chromosome. Males. XX chromosomes are female.
What type of sex chromosomes do females have?
Female have two X chromosomes while males have an X and a Y chromosome.
What are sex chromosomes that result in male?
XY Chromosomes = Males XX Chromosomes = Females
What what are sex chromosomes?
XX for a girl and XY for a boy
Do females have xx in every chromosome in their body?
By textbook, the genetic coding in every cell in a human's body should be exactly the same. So, yes, all females have the XX chromosomes in every cell of their body. Males will have the XY chromosome in every cell of their body.
What are xx chromosomes called?
The XX chromosome is female; the XY is male. They represent the 23 pair of human chromosomes
What combination of chromosomes is a female an a male?
Females typically have two X chromosomes (XX), while males typically have one X and one Y chromosome (XY).
When two individuals reproduce what are the chances of having a male offspring?
its a 50/50 since the girls chromosomes are xx and the guys chromosomes are xy the pairs which can be created are xx,xx,xy,xy for the offspring to become a male its a 2/4 chance which is 50% :)
The most obvious way the karyotypes of a sister and brother look different?
The most obvious difference in the karyotypes of a sister and brother would be the sex chromosomes. A sister would typically have two X chromosomes (XX) and a brother would have one X and one Y chromosome (XY). This difference in sex chromosomes would be clearly visible when examining their karyotypes.
