Mendelian genetics

Goals

1. To understand how Mendel's approach to genetics allowed him to uncover the rules governing inheritance

2. To understand the significance of Mendel's laws

3. To fully understand Mendelian inheritance by understanding the exceptions to his laws

4. To understand how the behavior of chromosomes during meiosis determines the ways that new combinations of genes can be formed.

5. To understand why genes located on the X chromosome have different patterns of expression and transmission than do genes located on autosomes.

Outline:

1. Gregor Mendel

a. genetics before Mendel

b. Mendel's background

c. about garden peas: how to choose a good experimental organism

2. Mendel's experiments

a. monohybrid crosses

dominant vs. recessive

The Law of Segregation

the testcross

b. dihybrid crosses

The Law of Independent Assortment

c. behavior during meiosis and fertilization

each individual has two

they separate during gamete formation

each pair behaves independently of all other pairs

3. Variations on a theme by Mendel

a. incomplete dominance

b. codominance

c. multiple alleles

d. pleiotropy

e. polygenic traits

additive effects

non-additive effects -- epistatis

4. The linkage of genes

linked genes have loci on the same chromosome

linked genes don't assort independently

the crossing over of linked genes during meiosis allows new combinations of alleles

crossing over allows the creation of linkage maps

5. Chromosomal basis of sex

a. sex determination

b. X chromosome inactivation

c. X-linked traits

 

Vocabulary

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