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)
1. A normal male,
exist.
2. A normal female

3. A female with Turner's Syndrome
4. A female with Triple X Syndrome
5. A male with Klinefelter's Syndrome
6. A male with Patau's Syndrome
7. A female with Patau's Syndrome
8. A male with Edward's Syndrome
9. A female with Edward's Syndrome
10. A male with Down's Syndrome
11. A female with Down's Syndrome
12. A male with Trisomy 22
13. A female with Trisomy 22
14. A male with XYY
MORE ONLINE PRACTICE….

Online practice:
https://bio.rutgers.edu/~gb101/lab10_meiosis/meiosis_web/10noteb
ook4.html

Review for quiz