2. The Origin of Genetics Chapter 10- Section 1 Ag Biology

3. What is Heredity? The passing of traits from parents to offspring Traits: any heritable character that varies among individuals (hair color, eye color, etc.)

4. Gregor Mendel Austrian Monk Studied heredity by breeding different varieties of Pisum sativum (garden pea) First person to develop rules that accurately predicted patterns in heredity His studies formed the basis of genetics He is called the “Father of Genetics”

5. T.A. Knight’s Contribution to Study of Genetics British farmer Crossed a variety of garden pea with purple flowers with a variety with white flowers Result: all offspring had purple flowers Then, he crossed 2 purple offspring and their offspring had both purple and white flowers White trait reappeared in second generation

6. How did Mendel’s research differ from Knight’s? Mendel took Knight’s experiment to the next level. He counted the numbers of each kind of offspring and analyzed the data This type of math analysis was on the cutting edge of research at the time

8. Quiz Time!!!!! 1. What did Mendel use to perform his genetic experiments? 2. What did Mendel do with Knight’s experiments?

9. 3. When the P generation plants were bred, purple with white, what did the offspring look like? 4. When the F1 generation was bred what did the offspring look like?

10. 5. Out of 4 plants in the F2 generation, how many were purple and how many were white?

11. Why were garden peas used to study heredity? Many traits that have two clearly different forms (easy to tell apart) They are self-fertilizing Small Mature quickly Many offspring Grows easily

12. The 7 traits studied by Mendel and their contrasting forms: Flower Color Seed Color Seed Shape Pod Color

13. The 7 traits studied by Mendel and their contrasting forms: Pod Shape Flower Position Plant Height

14. Monohybrid Cross A cross that involves one pair of contrasting traits Examples: crossing a plant with purple flowers with a plant with white flowers

15. Mendel’s Experimental Design Step 1: Mendel allowed each variety of garden pea to self-pollinate for several generations. (Ensured true-breeding) – True-Breeding: displaying only one form of a particular trait in offspring – Served as the parental generation (P generation)

16. Mendel’s Experimental Design Step 2: Mendel cross-pollinated two P generation plants with contrasting forms of a trait. Offspring are F 1 generation. Step 3: Mendel allowed the F 1 generation to self-pollinate. Offspring were called F2F2 generation.