1. 2/ th Grade Agenda
Learning Objective: Learn about Genetic Disorders
Collect HW: Reading & Note taking p. 102 – 103
Counselor Presentation
Text Book Reading: 195 – 200
HW: Reading & Note taking p. 104 – 106
Reminder HW: Science Fair Project due 3/3 & 3/4 (50 Points)

2. Reflection
Prompt: What are the 4 major blood types for humans? Which blood type is the universal donor blood type? Why?

3. Some human traits are controlled by a single gene that has more than two alleles
Blood type is controlled by three Alleles
What are the major human blood types?
A, B, AB & O
Which human blood type is a universal donor?
Blood Type: O

4. Many human traits are controlled by many genes
Four genes control height in humans
Skin, eye and hair color are controlled by multiple genes

5. What are the Female Sex Chromosomes?XX

6. What are the Male Sex Chromosomes?XY
Because there is some missing genetic information in the “Y” chromosomes, Males are more likely to get a sex-linked trait

7. Who determines whether the child is a boy or a girl ?
Father

8. How many pairs of chromosomes to humans have?23

9. Sex Linked Genes
Genes on the X and Y chromosomes are called sex linked genes
Most of the genes on the X chromosomes are not on the Y chromosomes
Since Males have the Y chromosomes they are missing an allele.

10. Red – Green colorblindness
More males have red – green color blindness then females
Why?

11. Red – Green colorblindness

12. Red – Green colorblindness

13. Genetic Disorders – Cystic Fibrosis
Cystic Fibrosis is a disorder in which the body produces abnormally thick mucus in the lun___ and intes_____.
The thick mucus fills the lungs making it hard for the affect person to breathe. gs
tines

14. Genetic Disorders – Sickle Cell Disease
Sickle shaped red blood cells clog blood vessels and cannot carry as much ox_____ as normal cells.
ygen

15. Genetic Disorders – Hemophilia
People with Hemophilia do not produce one of the prot_____ needed for normal clotting.
They can die from simple cuts and bruises
ein

16. Genetic Disorders – Down Syndrome
In Down syndrome, a person’s cells have an extra copy of chrom______ 21
People with Down syndrome have some degree of mental retar________
osome
dation