Agenda 1. Notes - Genetics2. Marshmallow Monsters3. Vocabulary strips

Warm-Up Question

1. Use the following terms to explain fertilization (haploid, diploid, gamete, zygote, chromosomes)?

VocabularyGenotype

Phenotype

Heterozygous

Homozygous

Dominant

Recessive

Allele

Mendel

Trait

Mendelian Genetics

Why do we look like our parents and

grandparents?

Gregor Mendel…He’s THE MAN

• He studied heredity, how characteristics or traits are passed from parents to offspring.

• To find out about heredity, Mendel studied pea plants.

Pea Plant

Why are some flowers purple and others white?

Trait

Trait

• A type of characteristic.

• Example:

Flower color, Plant height

Eye shape, Hair color

• What determines which traits you will have and which your kids will have?

Gene

• The genetic information on a chromosome for a characteristic.

• We have 2 copies of each gene, one from mom and one from dad.

Mom Dad

Genes

Gene for hair

Allele• Allele: Different forms of a

gene.• Different alleles code for

different traits.

ExampleFlower ColorW = Purplew = white

DadMom

W w

Dominant Allele

• Dominant Allele - prevents other genes from showing their traits.

• These are written with Capital Letters. (like B, R, W)

DadMom

Dominant

B b

Example of Dominance

• Pea plants may carry one allele from dad w for white flowers and one from mom W for purple flowers.

• Because W is dominant, the baby pea plant will have purple flowers.

Mom Dad

W w

Recessive Gene

• Recessive Gene - does not show its trait when there is a dominant gene.

• These are written with lowercase letters. a, b, c

Recessive

DadMom

B b

Example of Recessive Inheritance

• If a pea plant has WW or Ww they have a dominant gene and will have purple flowers.

• However if the pea plant has two recessive genes ww, their flowers will be white.

Mom Dad

ww

Genotype

• Genotype: The genes or alleles we have for a certain trait.

Example

• WW, Ww, or ww

• Homozygous - same (WW or ww)

• Heterozygous - different (Ww)

Phenotype

• The physical trait that is shown.

• The phenotype is determined by the genotype.

Example

• White flower, purple flower

• Brown eyes, blue eyes

Genotype and Phenotype

Purple Flower WW or Ww

White Flower ww

We do not know which genes we are going to pass to our children.

Mom Dad

A a A a

A A A a A a a a

Can you roll your tongue?

AgendaMendel LetterBikini Bottom WorksheetOompha Loopa Genetics

Giants Blue hair (B) is dominant to Eagles Green hair (b).

1. Write out the homozygous dominant, homozygous recessive, and heterozygous genotypes.

2. What is the phenotype for a Bb individual?

Law of Segregation• Before meiosis, the

original parent cell has 2 of every allele.

• During meiosis, the parent cell divides to form a gamete (sperm or eggs) which have only 1 of every allele.

e

h

E

H

E

h

e

H

E

H

e

h

E

h

e

H

E = brown eyes H = black hair

e = blue eyes h = red hair

Law of Independent Assortment

• The separation of one pair of alleles does not influence the separation of another pair of alleles.

Generation

• All the individuals and offspring born and living at the same time.

Do you have a widow’s peak?

Are your earlobes attached?