Friday January 7 th Using your prior knowledge of genetics, explain how two brown rabbits could have white offspring. 1

Brain Pop Video 2

Goal #1: Gregor Mendel 3

I. Heredity = I. Heredity = the passing of traits from parent to offspring 4

A. Concepts of heredity 1. genes determine traits 1. genes determine traits 2. genes are found on 2. genes are found on chromosomes chromosomes 3. genes are made up of 3. genes are made up of DNA DNA 4. genes separate during 4. genes separate during meiosis meiosis - each gamete receives - each gamete receives different genes (some different genes (some from mom, some from from mom, some from dad) dad) 5

For Example: You may have attached earlobes But your brother/sister may have free earlobes This means the gene for earlobes took on one form of a trait for one of you and another form for your brother/sister. 6

B. Alleles: different forms of a gene for a trait a. alleles separate into sex cells during meiosis b. can be dominant or recessive (A or a) 7

C. Traits: characteristics that vary between individuals What are some examples of traits? ex: hair color, eye color, etc. 8

Genetics: D. Genetics: the study of how alleles affect generations of offspring 9

II. Father of genetics: Gregor Mendel A. History 1. He was a monk 2. Experimented with pea plants 3.Died in 1884 with no recognition for his scientific discoveries. 10

B. Mendel’s experiments 1.Mendel chose peas because they were easy to breed for pure traits. 2. Purebreed (true- breed): organisms that always produce the same traits. Ex: tall plants always produce tall plants 11

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3. Self-pollination: taking pollen from the male reproductive structures (anthers) and placing it on the female reproductive structures (stigma) on the SAME plant –1 parent: offspring are identical to parent 13

4. Cross-pollination: taking pollen from the male reproductive structures and placing it on the female reproductive structures on a DIFFERENT plant. –2 parents – offspring not always identical to parents –hybrids: crosses of different parents that have different traits 14

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a. Mendel crossed a parent generation (P1), of a pure tall plant with a pure short plant. –offspring called the first filial generation (F1) –Results: ALL tall plants. 16

b. Mendel then crossed these offspring (the 1st generation, the F1) of all tall plants and planted the seeds. –new offspring called the second filial generation (F2), –Results: 3 tall plants and 1 short plant (3:1) How did this occur? 17

C. Mendel’s Principle of Dominance 1. Dominance: form of a trait that masks another form of a trait –P 2. Recessive: form of a trait that is masked - p 18

III. Probability: science that helps determine the chance that something will take place. a. multiple trials provide more accurate results. b. Scientific research is based on accurate, repeatable results. 19

C#1: Gregor Mendel Construct a flowchart on Mendel’s Methods for breeding pea plants. Include as many vocab words as possible. Include P1 and F1 crosses and results 5 Create a diagram/picture on Mendel’s principles of dominance and segregation. Describe why it is important for alleles to segregate during gamete formation (meiosis). 10 Create a collage comparing Mendel’s Laws. Use Goal #1 – be creative and use your own imagination Section Assessment – must be in complete sentences 5 20