1. Are there exceptions to mendel’s ideas of dominant and recessive?

2. YES!!

3. What do you think would happen? How about mendel?

4. According to mendel, we should see 100% red heterozygous offspring..

5. We see this instead. RR WW RW

6. Complex Patterns of Inheritance
(GET EXCITED!!)

7. = + Incomplete dominance
With incomplete dominance, neither allele is completely dominant nor completely recessive.
--> Heterozygous phenotype is an ______________ between the two homozygous phenotypes
intermediate = +

8. Incomplete
dominance

9. codominance
With codominance, both alleles are dominant and equally expressed.
--> both alleles express themselves in a heterozygous organism
for example,
fully
roan cows
and sickle cell anemia + =

10. codominance +

11. Sickle cell anemia
Normal red blood cell
Sickle cell

13. Changes in hemoglobin cause red blood cells to change to a sickle shape.
People who are heterozygous for the trait have both normal and sickle-shaped cells.

15. symptoms Sickle red blood cells clump together
and stick to the walls of blood vessels, blocking blood flow.
This can cause severe pain and permanent damage:
brain, heart, lungs, kidneys, liver, bones, and spleen.

16. Polygenic traits Traits that are influenced by ____________________
for example, skin color, height, eye color, and fingerprint pattern
multiple gene pairs

20. Multiple alleles form of inheritance that is determined by _________
__________
for example, human blood types
more than
2 alleles
-Type A
-Type B
-Type AB
-Type O

21. Blood types Antigens are ___________ foreign to the _____.
Rh factors can either be ___________ or _____________
substances
body + -