KARYOTYPING

DO NOW- REVIEW:

How many chromosomes do we have?

Why do we have 2 (sets) of chromosomes? What are these called?

How can you tell the gender based on a karyotype? What are the genotypes of each?

Sex chromosomes vs. autosomes?

What is it about the Y that forms males as opposed to the X that forms females?

KARYOTYPE How many chromosomes do we have?

Why do we have 2 (sets) of chromosomes? What are these called?

How can you tell the gender based on a karyotype? What are the genotypes of each?

Is this picture taken before or after the S phase?

Sex chromosomes vs. autosomes?

What is it about the Y that forms males as opposed to the X that forms females?

SRY GENE and development.

What is the SrY gene?

What does it produce?

Why does it matter when testosterone is present in development?

DEVELOPMENT

INTERNAL (7-8 weeks) Testosterone? Male

NO testosterone? Female

EXTERNAL (2-3 months) Testosterone? Male

NO testosterone? Female

PRACTICE PROBLEM

A female boy builder is taking steroids (testosterone). She doesn’t realize she becomes pregnant until 10 weeks. A sperm carrying an X fertilized her egg. After she finds out she is pregnant, she immediately stops taking steroids and the rest of the pregnancy.

What is the child’s genotype?______

What is the child’s gender (genotipically)? ________

What internal organs does the child have? __________

What external organs does this child have? __________

How would this child develop? _____________________

MORE KARYOTYPING

DO NOW:

What are karyotypes used for?

How are the chromosomes arranged?

Which sex chromosome determines gender? Why?

How can you determine the kind of disorder based on a karyotype?

ONLINE ACTIVITY: http://www.biology.arizona.edu/human_bio/activities/karyotyping/karyotyping.html

ABNORMALITIES: Research the karyotypes of the following and indicate what abnormalities (if any) exist. 1. A normal male,

2. A normal female3. A female with Turner's Syndrome4. A female with Triple X Syndrome5. A male with Klinefelter's Syndrome6. A male with Patau's Syndrome7. A female with Patau's Syndrome8. A male with Edward's Syndrome9. A female with Edward's Syndrome10. A male with Down's Syndrome11. A female with Down's Syndrome12. A male with Trisomy 2213. A female with Trisomy 2214. A male with XYY

MORE ONLINE PRACTICE….

Online practice: https://bio.rutgers.edu/~gb101/lab10_meiosis/meiosis_web/10notebook4.html

Review for quiz