Wake-up1. Label each number in the diagram below. Use

translation notes for assistance.

Mendelian Genetics

Who is Gregor Mendel?

• Raised in a poor farming family; joined the monastery to get an education

• Became the gardener of the monastery

• Noticed differences between plants; particularly pea plants

• Father of Genetics

Why peas?

1. Cheap

Why peas?

2. Peas grow very fast

Why peas?

3. Peas are easy to manipulate during reproduction

Why peas?

4. Peas have many traits to examine

Anatomy of a Flower

Petal

Ovary: Eggs

Anther: Pollen

Pistil = Female

Stamen = Male

Plant Fertilization

Self Pollination

Plant fertilizes it own eggs

Cross Pollination Pollen from one flower fertilizes the egg of another

Mendel’s Experiment: P generation

Parent Generation

Mendel selected one pea trait to examine at

a time:

Flower color

Mendel cross pollinated a purple flower with a white flower

Mendel’s Experiment: P generation

What do you think Mendel found?

What would be the result of

crossing a purple flower with a white flower?

First GenerationF1 generation: First generation (offspring of P gen)

Mendel found that the resulting plants ALL had purple flowers

Mendel decided to let the F1 generation to self-pollinate (fertilize own eggs)

2nd Generation

F2 generation: Second generation

(offspring of F1)

Mendel found that the resulting

generation had purple and white

flowers; in a 3 to 1 ratio

Conclusions: What does all of this mean?1. Individuals inherit “factors” from parents

Conclusions: What does all of this mean?

2. These “factors” are

passed from one generation to the

next

Conclusions: What does all of this mean?3. “Factors” may be passed along, but may not

show up in offspring

Where is green?

Gregor Mendel

Wake-up

1. Who is the father of genetics?

2. Explain the difference between the P generation and the F1 generation.

3. How does the F2 generation fit in?

34 years later … Mendel explained:1. The “factor” is a gene; part of DNA that codes for a

trait; Flower color is a gene

34 years later … Mendel explained:

2. An allele is two different forms of a gene; Purple and White flowers

34 years later … Mendel explained:

3. On average, there are two alleles for each trait; one from mom and one from dad

Dominant and Recessive AllelesDOMINANT allele: Expressed trait; Capital

letter, Always first

Dominant and Recessive Allelesrecessive allele: Only expressed if paired with

another recessive; Lowercase letter

What is genotype?Combination of alleles; allele letters that code

for a trait; GENETIC makeup of gene

Types of Genotypes

a. Homozygous Dominant: Two dominant alleles

BB

Types of Genotypes

b. Homozygous Recessive: Two recessive alleles

bb

Types of Genotypes

c. Heterozygous: One dominant and one recessive allele

Bb

What is phenotype?

Physical expression of trait; observable characteristic; physical appearance

Example

B = Big nose and b = small nose

What would be the phenotype

for the following:a. BBb. Bbc. bb

Example

B = Big nose and b = small nose

What would be the genotype for

the following:a. BBb. Bbc. bb

G = Green hair H = Hairy ears

g = Purple hair h = Smooth ears

Baby Lab

• Heads: Dominant allele; N1, etc

• Tails: Recessive allele; N2, etc