http://www.nlm.nih.gov/medlineplus/ency/article/000379.htm
After reading the information, provided in the above link, answer the following questions:
a) Explain how it is genetically possible (in terms of mitosis and meiosis) for a fertilized egg to have 45 chromosomes.
b) In the case of Turner Syndrome are the autosomal chromosomes affected? Explain your answer
c) Explain how a karyote could inform a pregnant mother as to whether or not her unborn child has Turner Syndrome
A)It is genetically possible for a fertilized egg to have 45 chromosomes instead of 46 because in the case of Turner Syndrome, on x chromosome is missing or part of it is missing.
ReplyDeleteB)In Turner Syndrome autosomal chromosomes are not affected because they are not sex cells. Only the x chromosomes are affected which determine sex.
C)Karyote can inform a pregnant mother as to whether her unborn child has Turner Syndrome or not because it can identify genetic problems by observing sample cells.This is preformed by counting the number of chromosomes or looking for structural changes in chromosomes.
a) It is genetically possible for a fertilized egg to have 45 chromosomes because with Turner Syndrome, cells are missing all or part of an X chromosome.
ReplyDeleteA. Humans have 46 chromosomes. They receive one from your gametes. It becomes possible because there may be a defect in one of the gametes that comes in contact with one another and that may affect the unborn in ways of growth and development. Certain things such as this can result in one X chromosome or half of an X.
ReplyDeleteB. Humans have 44 autosomal chromosomes. The autosomal chromosomes are not affected. Turner syndrome only affects the sex chromosomes in a female.
C. If will show if the X chromosome has been formed properly.
A)Every human should have 46 chromosomes. However, if anything goes wrong during the development stage of a fetus, it can lead to an irregular number of chromosomes,which can lead to genetic mutations and birth defects like Turner Syndrome(a female is born missing an X chromosome)and down syndrome(a baby is born with 47 chromosomes).
ReplyDeleteB)Turner Syndrome does not affect the autosomal chromosomes, because they are not gametes, and Turner Syndrome only occurs in a womans sex cells.
C)A karyotype would show the genetic make up of the fetus once it is developed enough, therefore, the mother would be able to tell if the baby had the expected number of chromosomes.
Hi guys you have made some very keen observations, however there are some minor changes/corrections that are required:
ReplyDeleteBrittany explain how it is possible for a fertilized egg to contain only 45 chromosomes.
Raven your statement about "cells" being missing from a fertilized egg is inaccurate. Explain why and correct/complete your comment.
Sheniqua rethink this statement "cells are missing parts of an X chromosome," and correct letter B
Quonshia make corrections to A and complete your comment.
In addition to my earlier post, Normally every human is created with 46 chromosomes, but if something goes wrong during the process of development then the fetus can be left with to many or not enough chromosomes.In Turner syndrome, cells are missing all or part of an X chromosome. So normally when the fertilized egg has two x chromosomes they will only have one, or two with one partially missing.
ReplyDeleteHi all, now that we have more throughly discussed chromosomal abnormalities which may cause genetic disorders, I need you to update your post to Turners syndrome and discuss the chromosomal inheritance which causes Turners Syndrome. And since you are all good little AP Bio. students I know you will remember to include mitosis and meiosis in your answers.
ReplyDeleteTo conclude earlier posts, If either of the aberrant gametes unties with a normal one at fertilization, the zygote will also have an abnormal number of a chromosome, a condition known as aneuploidy. Fertilization involving a gamete that has no copy of a particular chromosome will lead to missing chromosome in the zygote. The aneuploid zygote is said to be monosomic for that chromosome. If a chromosome is present in triplicate in the zygote, the aneuploid cell is trisomic for that chromosome.
ReplyDeleteIf the abnormal sex cell unites with a normal one then the zygote will have an abnormal number of a chromosome. Mitosis transmit the anomaly to all embryonic cells. If the organism survives, it usually has a set of traits caused by abnormal dose of the genes associated with thr extra or missing chromosome.
ReplyDelete