What are the X and Y chromosomes?

Really simply, they are the chromosomes which decide whether you’re a boy or a girl. In total we have 46 chromosomes so 23 pairs which sequence everything about us- from the colour of our eyes to the how tall we can be. The first 22 pairs of chromosomes are matched but the last pair are either an XX or an XY. For each of these chromosomes you get one from your mom and one from your dad. Males have an XY chromosome (so you can either get an X or a Y chromosome from your dad)females have XX chromosomes (so you can only get an X from your mom)The Y chromosome causes male characteristics.There is a 50% chance of getting an XX chromosome and 50% chance of getting an XY pair so 50% chance of being a male or female and we can see this when we draw a punnet square (genetic diagram.)(Draw a genetic diagram)important points to remember when constructing genetic diagrams Put possible gametes of one parent on top of the diagram and the other down the side you then fill in the letters - the letters in the middle are the possible combinations you could get so you get aa 50-50 chance - remember this is for each pregnancy so just because you get a girl the first pregnancy doesn’t mean you have a higher chance of getting a boy next time