- Determine the sex of an organism
- Considered the 23rd chromosome pair
- XY in males while XX in females
- 22 other chromosomal pairs are called autosomes
- Several disorders are known to be associated with an odd numbers of sex chromosomes
Reflection:
Sex chromosomes are known to determine the sex of an organism. They make up the 23rd pair of chromosomes in the average human. Eggs fertilized by X bearing sperm become females (XX) while eggs fertilized by Y bearing sperm become males (XY). Unlike autosomes, in which each individual of the pair carries the same forms (alleles) of the same genes, sex chromosomes do not carry identical genetic information. The X chromosome, being larger, carries more genes than the Y chromosome does. Recessive sex-linked traits, such as red-green colorblindness and hemophilia, occur much more frequently in men than in women. This is because if a man receives the recessive allele from a woman's X chromosome, then his Y chromosome will have no allele to counteract its effects, making him prone to the disorder. However, a female must receive two recessive alleles on both her X chromosomes to fully display the trait. Though is most be on both X chromosomes to be fully displayed, it can be shown once to make the woman a "carrier", which may have minor symptoms of the disorder. I learned this information in class from Mr. Black, whom did a great job teaching what sex chromosomes were and how they can be affected by sex-linked traits and disorders. I never would've realized how lucky women are in the fact that they have a second opportunity to not have a disorder or trait all because of their second X chromosome. I personally liked this topic because it broadened my knowledge of sex chromosomes and sex-linked traits and how men are affected much more than women.
Citations:
"Sex Chromosome | Genetics". Encyclopedia Britannica. N.p., 2016. Web. 27 Nov. 2016.
"DNA & Its Job 2010G10r3b - (A) Chromosomes". 2010g09r3bdnawiki.wikispaces.com. N.p., 2016. Web. 27 Nov. 2016.
Great Blog!!! Very well written and understandable. Your information was outstanding and it seemed like you new a lot about this topic. One question I have is why is the X chromosome so much bigger than the Y chromosome. I really enjoyed this Blog because of all the information in it and I now understand sex chromosomes a lot more. Very good Blog!!
ReplyDeleteThe reason the X chromosome is bigger than the Y is because it is able to contain more genes than the Y. Thank you for your comments!
DeleteGreat job! I loved reading this, Great information, the question I have is Why do Females and males have different chromsomes make ups (XY)(XX).
ReplyDeleteThank you Ryan. The reason why males have different chromosomal makeup than females is because the Y chromosome gives the genetic information to make a male a male. The Y chromosome is mostly responsible for the genetic makeup of sexual organs in males and the ability to produce sperm.
DeleteGreat blog, very well written!!
ReplyDeleteGreat Blog!!!!! My question is, what if the sex chromosome had 3 on it instead of 2?
ReplyDeleteGood question!! It doesn't really cause any harmful affects, having a female with XXX or more rarely XXXX could just cause them to be taller or have longer legs than normal females. However, for males with XXY or XXXY it can cause them to have more feminine bodies and voices. But males with XYY are usually extremely tall and have high levels of testosterone.
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