4.04 genetic disorders
part i.
part i. you have learned that normally humans have 46 chromosomes (23 from the mother and 23 from the father). however, sometimes errors occur that cause the human to have abnormal numbers of chromosomes which lead to genetic disorders such as down syndrome and turner syndrome.
complete the chart below and then answer the question at the bottom of this page. refer to the lesson to you with the chart about down syndrome and turner syndrome:
genetic disorder down syndrome turner syndrome
instead of the normal 46 chromosomes, how many chromosomes occur with each syndrome?
tell which of the following chromosome errors exist with each syndrome (deletion, insertion, translocation, non-disjunction, substitution, inversion, frame-shift, point mutations) and write the definition for it.
health problems
treatment

1. turner syndrome involves a sex chromosome error and down syndrome involves an autosome or body chromosome error. which condition seems to have a greater influence on a person’s health: error of an autosome or error of a sex chromosome? explain your answer.

part ii
during meiosis there is an exchange of genes between chromosomes. each egg and sperm has a unique blend of genes. you learned how combinations occur in your lesson.
create a diagram below to show how crossing-over occurs and how it creates new gene combinations on each chromosome. be sure to
• label the parts of the chromosome,
• clearly illustrate the crossing over principle, and
• include explanations to clarify your drawing.
you may use word drawing tools to make your diagram. you may also make your drawing on scrap paper and scan or insert a photograph of your drawing, as long as labels and explanations are clear. if you desire, you can build a model with pipe cleaners, yarn, etc. as long as your diagram is your original work include the information above, it is acceptable.

insert diagram here.