1. AIM: How do organisms inherit genetic information from their parents? 4/16/13 DO NOW: 1. Pick up today’s quiz HOMEWORK: ILS Review Book 1.Read p. 23-25 2.Answer Questions #1-19 on p. 27-33 in your review book. DUE- Tomorrow

2. What are genes? Contains hereditary information Composed of DNA What determines your traits? One or many pairs of your genes. Where do you inherit you traits from? Mom & Dad

3. How does sexual reproduction differ from asexual reproduction? Sexual – Combination of genes (traits) from sperm & egg. Asexual – exact copy of the genes (traits) from the parent cell.

4. What is a dominant trait? A trait that hides (overshadows) the affect of another What is a recessive trait? A trait whose affect may be hidden by a dominant trait. How do geneticists indicate whether a trait is dominant or recessive? Dominant = Capital Letter “G” Recessive = Lowercase letter “g”

5. How do geneticists represent the genes for a particular trait? Genotype: GG, Gg, gg One gene from mom & one from dad How do homozygous genes differ from heterozygous genes? Homozygous = Pure (GG, gg) Heterozygous = Hybrid (Gg)

6. What is phenotype? The observable trait as a result of the gene combination What are the phenotype of the following? G= Green pods g= Yellow pods GG = Green pods Gg = Green pods gg= Yellow pods

7. How can we predict the probability of a trait being expressed? Punnett squares Pedigree charts According to the punnett square at left, what is the probability of Green Pods? Yellow Pods? Green = 3/4 or 75% Yellow = 1/4 or 25%

8. A Punnett square is shown at right. The dominant trait is represented by R. The recessive trait is represented by r. What percentage of the offspring will most likely show the dominant trait? 75% Dominant 25% Recessive

10. What is the probability of offspring with the tongue roller trait? Mom = Rr Dad= rr Mom = Rr Dad = Rr

11. How are males represented in a pedigree chart? Males = Squares How are females represented in a pedigree chart? Females = circles How can you determine the offspring from a couple?