Name: ______________________________ Period: _____

Mendelian Genetics

10.1 Mendelian Genetics

Genetics:

Heredity:

Traits:

Examples of traits:

In the 1800s an Austrian Monk studied plants. His name was

______________ _______________. He is called the “______________ _____ _________________”.

Mendel wanted to describe how traits were passed between ______________________.

Mendel’s Experiment:

Performed experiment using ______________ plants.

Why pea plants?

*

*

*

Pea plant traits

1. Flower color

2. Flower position

3. Seed color

4. Seed shape

5. Pod shape

6. Pod color

7. Plant height

Step 1:

Mendel looked at one trait, the ____________ _____________.

Mendel allowed the pea plants to ________ ______________. This gave ______________ plants

for the offspring.

Purebred:

He called these plants the _____ (Parental) ____________________.

Step 2:

Cross-pollinated two P generation plants.

Cross:

Flowers were all ______________. He called these plants the _______ ____________________.

F1 generation is the offspring of the P generation.

Step 3:

Allowed F1 generation to self-pollinate. Produced a mixture of ____________ and

_______________ flowers. He called this generation the _________ ___________________.

Overall:

10.2 Inheritance Theory

For each inherited characteristic an individual has 2 copies of a gene. These copies

are called _________________. Alleles are represented by _____________________.

Ex.

Dominant alleles:

Ex.

Recessive alleles:

Ex.

Let’s Try

Purple is dominant to white in flower color.

What color is PP?

What color is pp?

What color is Pp?

Vocabulary

Homozygous:

Homozygous dominant:

Homozygous recessive:

Heterozygous:

Genotype:

Phenotype:

Law of Segregation:

Punnett Squares:

Your mother is homozygous for black hair and your dad has blonde hair. Black is dominant to blonde.

What is the genotype of an organism that displays the dominant phenotype?

*

How can we figure out if the organism is PP or Pp?

Perform a _____________________.

Law of Independent Assortment:

Dihybrid cross:

Mendel crossed a true-breeding plant with round yellow seeds (RRYY) with a true-breeding plant grown from wrinkled green seeds (rryy)

What would the offspring’s phenotype be?

*

He then self pollinated the offspring.

10.3 Variations of Inheritance

What color if the offspring when you cross a black chicken with a white chicken?

*

Intermediate inheritance or incomplete dominance:

Codominance:

What are the four blood types?1. 2. 3. 4.

Blood Type GenotypeABABO

Polygenic Inheritance:

Importance of Environment

If a woman who is 6 ‘3’ and mates with a male who is 6 ‘7’… does that mean their son or daughter will be tall? Why?

*

The same plant can grow tall or short depending on water and sunlight. Think of professional athletes!

_____________________ can also effect the phenotype. Siamese cats usually have white fur but when there is cooler temperatures it changes the cats enzyme which makes the coat color darker.

10.4 Meiosis Explains Mendel’s Principles

Chromosome theory of inheritance:

All advanced organisms have chromosomes. Half the chromosomes come from the

___________ and half from the _________________.

When genes are located close to each other the greater the _______________ _____________.

Genetic linkage:

10.5 Sex-linked traits

Humans have ________ pairs of chromosomes. One set of chromosomes are called

_________ chromosomes. If your chromosomes are XX you are a _______________. If your

chromosomes are XY you are a _________________.

Any gene that is located on the sex chromosome is called ___________ _______________

gene. In humans most sex linked genes are located on the X chromosome because it

is much bigger than the Y chromosome.

XB

Xb

Xb

XB

Xb

Xb

Xb

Y XB

Y Xb

Y

Colorblindness is inherited as sex linked X recessive traits.