Exam #3 Th 12/6 in class Homework #4 is due 12/4/07 (only if needed) Bonus #2 posted Year End Topics: mtDNA Mapping Probability Evolution and the Origin of Humans

PhenotypeGenotype Genes code for proteins (or RNA). These gene products give rise to traits… It is rarely this simple. Figs

The relationship between genes and traits is often complex Complexities include: Complex relationships between alleles Multiple genes controlling one trait One gene controlling multiple traits Environmental effects

The colors of peppers are determined by the interaction of several genes

Fig Complexity of inheritance leads to genetic diversity.

Eye color: One trait controlled by multiple genes

Fig 6.7 Seven alleles and their interactions in leaf patterning of clover

The relationship between genes and traits is often complex Complexities include: Complex relationships between alleles Multiple genes controlling one trait One gene controlling multiple traits Environmental effects

1 gene controlling many traits

Mom = HSDad = HS H or S HH HSSS HS possible offspring 75% Normal 25% Sickle-cell Mom Dad Sickle-Cell Anemia S=sickle-cell H=normal

Coincidence of malaria and sickle-cell anemia

Mom = HSDad = HS H or S HH HSSS HS possible offspring Oxygen transport: 75% Normal 25% Sickle-cell Malaria resistance: 75% resistant 25% susceptible Mom Dad Sickle-Cell Anemia S=sickle-cell H=normal

The relationship between genes and traits is often complex Complexities include: Complex relationships between alleles Multiple genes controlling one trait One gene controlling multiple traits Environmental effects

What is different about these plants?

grown in acidic soil grown in basic soil Environmental Variation

Inheritance can be predicted by probability

Fig 3.07 Probability of a 4= 1/6 Probability of two 4’s in a row= 1/6x1/6=1/36

Fig 3.07 Probability of 3 or 4 = 1/6+1/6= 1/3

Fig 3.07 “and” multiply “or” add

Fig 6.5 Sickled and normal red blood cells

Huntington’s Disease D=disease d=normal Neurological disease, symptoms begin around 40 years old.

Mom = ddDad = Dd d or d D or d Dd dd possible offspring 50% Huntington’s 50% Normal Mom Dad Huntington’s Disease D=disease d=normal

Two different people: One with Huntington’s disease = Dd Hh One without Huntington’s disease = dd Hh mate. What is the probability that their offspring will have Huntington’s disease and sickle cell anemia? (Dd hh)

Two people: One with Huntington’s disease = Dd Hh One without Huntington’s disease = dd Hh mate. What is the probability that their offspring will have Huntington’s disease and sickle cell anemia? Dd hh Probability of each outcome: Probability of Dd (Ddxdd) =.5 Probability of hh (HhxHh) =.25

Two people: One with Huntington’s disease = Dd Hh One without Huntington’s disease = dd Hh mate. What is the probability that their offspring will have Huntington’s disease and sickle cell anemia? Dd hh Probability of each outcome: Probability of Dd (Ddxdd) =.5 Probability of hh (HhxHh) =.25 Multiply both probabilities.25 X.5 = 12.5% chance Dd hh offspring

How do individuals and groups with different genes arise? Evolution… Does it occur? If so, how does it occur?

Does evolution occur?

As DNA changes; traits change. Protein

Evolution: A species’ genetic component changes as the individuals reproduce.

Evolution: A species’ genetic component changes as the individuals reproduce. These changes are based on how the DNA changes and who reproduces.

O O OOO O O OO OO Bacteria with mutation causing resistance Evolution: changes in DNA as information transmitted

O O OOO O O OO OO O O OOO O O OO OO Apply antibiotic X XX XXXX X XX Kills most bacteria. Except if some have mutation that allow them to be resistant. Bacteria with mutation causing resistance Evolution: changes in DNA as information transmitted

O O OOO O O OO OO O O OOO O O OO OO O Apply antibiotic X XX XXXX X XX Kills most bacteria. Except if some have mutation that allow them to be resistant. Continues to replicate Bacteria with mutation causing resistance Evolution: changes in DNA as information transmitted

O O OOO O O OO OO O O OOO O O OO OO O O OOO O O OO OO O Apply antibiotic X XX XXXX X XX Kills most bacteria. Except if some have mutation that allow them to be resistant. Continues to replicate Population of resistant bacteria Bacteria with mutation causing resistance Evolution: changes in DNA as information transmitted

Next we will look at what DNA can tell us about the origins of Homo sapiens.