11-1 The Work of Gregor Mendel Atwater Agriculture Department

11-1 Vocabulary Genetics: – the scientific study of heredity You get your genetics from your ______. _____, _____, and ______ are examples of genetics.

Think Pair Share Together, explain what a genetics are. 1)What are genetics? 2)Where do you get your genetics from? Genetics are _______. We get our genetics from ________.

True-breeding- – term used to describe organisms that produce offspring identical to themselves if allowed to self-pollinate True-breeding happens in _____ when they self-pollinate.

Think Pair Share Together, explain what true breeding is. 1)What is true breeding? 2)What is an example of true breeding? True breeding is _______. An example of true breeding is ________.

Trait- –specific characteristic that varies from one individual to another –_________ would be a trait that your parents gave you.

Think Pair Share Together, explain what a trait is and give an example. Sentence for Trait Give one example Definition for Trait Give one example

11-1 Vocabulary Hybrid- –offspring of crosses between parents with different traits A ________ is an example of a hybrid because _________.

Gene- –sequence of DNA that codes for protein and thus determines a trait –A gene codes for traits such as ______, ______, _______ and _______.

Allele- –one of a number of different forms of a gene –An allele is a part of the chromosome

Think Pair Share Together, explain what an allele is. 1)What is an allele? 2)Where are alleles located at? An allele is _______. An allele can be found ________.

11-1 Vocabulary Segregation- –separation of alleles during gamete formation Segregation means _____________. Allele

Think Pair Share Together, explain what segregation is. When does segregation happen? Segregation happens_____________.

Gamete- –specialized cell involved in sexual reproduction Gamete is another word for _______ or _________ cells.

11-1 Notes 1.Genes and Dominance a.Mendel studied different traits with contrasting characteristics b.Traits- a specific characteristic such as seed color or plant height that varies from one individual to another. c.Hybrids- Offspring of parent crosses with different traits d.Genes- chemical factors that determine traits (height) e.Alleles- different forms of a gene (short or tall)

11-1 Notes f.Principle of dominance: Alleles can be dominant or recessive i.Dominant: trait is always seen Ii. Recessive: trait is seen if dominant is not present

Think Pair Share Together, compare and contrast dominant and recessive traits. 1)What does Dominant mean? 2)What does recessive mean? Dominant means_____ Recessive means ________.

11-1 Notes 2.Explaining the F 1 Cross a.Segregation- separation of alleles b.Gametes- sex cells (during formation plant alleles were segregated) c.Law of Segregation: Alleles for each trait are randomly separated during formation of sex cells (gametes)

P Generation F 1 Generation F 2 Generation TallShortTall Short Section 11-1 Principles of Dominance Go to Section:

P Generation F 1 Generation F 2 Generation TallShortTall Short Section 11-1 Principles of Dominance Go to Section:

P Generation F 1 Generation F 2 Generation TallShortTall Short Section 11-1 Principles of Dominance Go to Section:

Seed Shape Flower Position Seed Coat Color Seed Color Pod Color Plant Height Pod Shape Round Wrinkled Round Yellow Green Gray White Smooth Constricted Green Yellow Axial Terminal Tall Short YellowGraySmoothGreenAxialTall Section 11-1 Figure 11-3 Mendel’s Seven F 1 Crosses on Pea Plants Go to Section:

11-1 Review What are dominant and recessive alleles? –Dominant allele: allele whose from of a trait always show up in an organism if the dominant allele is present –Recessive allele: allele whose form of a trait shows up only when the dominant allele is not present.

11-1 Review What is segregation? What happens to alleles during segregation? –Separation of paired alleles; the alleles are separated during the formation of gametes, with the result that each gamete carries only a single allele from the original pair. What did Mendel conclude determines biological inheritance? –Factors that are passed from one generation to the next.

11-1 Review Describe how Mendel cross pollinated pea plants.. –Mendel cut away the male parts of one flower, then dusted it with pollen from another flower. Why were true-breeding pea plants important for Mendel’s experiments? –True-breeding pea plants have two identical alleles for a gene, so in a genetic cross each parent contributed only one from of a gene, making inheritance patterns more detectable