1. Bell Work: 2/21/14
Turn in Extra Credit of the Week in Classwork Turn In!!
Take out your HW.
Get the notes pages off table 5 and 7.
Label pg.137 “Heredity Notes”.
Label pg.138 “Traits and Inheritance”.
Label pg.139 “Heredity Review WS”.
Get a Textbook and read pgs
“Who Was Gregor Mendel?
“Unraveling the Mystery”
“Self-Polinating Peas”

2. Heredity Why don’t you look like a rhinoceros?
The answer to this question seems simple: Neither of your parents is a rhinoceros.
But there is more to this answer than meets the eye.
As it turns out, heredity, or the passing of traits from parents to offspring, is more complicated than you might think.
For example, you may have curly hair, while both of your parents have straight hair. You might have blue eyes while both of your parents have brown eyes.
How does this happen?

3. Who was Gregor Mendel?
Gregor Mendel discovered the principles of heredity while studying the characteristics and traits of pea plants.
A characteristic is a feature that has different forms in a population.
For example, hair color is a characteristic of humans.
The different forms, such as brown or red hair is called a trait.

4. Mendel’s First Experiments
One trait was always present in the first generation, and the other trait seemed to disappear.
Mendel chose to call the trait that appeared the dominant trait.
Because the other trait seemed to fade into the background, Mendel called it the recessive trait.
The recessive trait for the white flower reappeared in the second generation.

5. Review: Talk with your group…
What is heredity?
The passing of genetic traits from parent to offspring
Who was Gregor Mendel?
Discovered the principles, or ideas, of heredity
Which trait is present in the first generation?
Dominant trait
Which trait is present in the second generation?
Recessive trait

6. Traits and Inheritance
Mendel knew from his experiment with pea plants that there must be two sets of instructions for each characteristic.
These instructions for an inherited trait are called genes.
Each parent gives one set of genes to the offspring.
The offspring then has two forms of the same gene for every characteristic- one from each parent.
The two forms (often dominant and recessive) of a gene are known as alleles.
Dominant alleles are shown with a capital letter (P for dominant purple flowers).
Recessive alleles are shown with a lowercase letter (p for recessive white flowers).

7. Phenotype & Genotype Genes affect the traits of an offspring.
An organism’s appearance (the way they look) is known as its phenotype.
In pea plants, possible phenotypes for the characteristic of flower color would be purple flowers or white flowers.
The genotype of an organism is the entire genetic makeup of an organism; the combination of genes for a specific trait.
An organism with two dominant or two recessive alleles is homozygous (same size letters).
An organism with one of each (Pp) is heterozygous.

8. Exit Slip Fill out your Exit Slip (Index Card) with:
List 3 things you learned…
List 1 thing you are still confused about…
(On Back) Explain why this lesson was valuable.

9. Bell Work: 2/24/14 p. 7mins Label pg.140 “Punnett Squares”.
Take out agendas for grade reports.
Get a Textbook read page p
Get your remote!
Answer the following questions on pg.139
What is incomplete dominance?
Give an example like in the book!
Ex: Blue and Yellow apples make Green apples 9

10. Punnett Square
A Punnett square is used to organize all possible combinations of offspring from particular parents.
Genotype PP is a purebred.
What is the genotype for the offspring to the right?
The dominant allele P ensures that the offspring will have purple flowers.
The recessive allele p may get passed to the next generation.
Why?

11. Quick Lab pg. 107 Work with your group to complete the Punnett square.
What would be the phenotypes for these offspring?
RR= round seeds
Rr= round seeds
rr= wrinkled seeds R r RR
(genotype- two dominant alleles) Rr
(genotype- one dominant allele,one recessive allele) rr
(genotype- two recessive alleles) R r

12. Bell Work: 2/25/14 p. 7mins Take out grade reports.
Extra Credit due Friday!
Get the Quizlet app and USE IT!!
Write your answers for the following on pg.139. Match the terms on the left to a term on the right.
Genes
Traits
Phenotype
Punnett Square
Probability
Genotype
Example of a Phenotype
Characteristic
Dominant Allele
Example of a Genotype
Alleles
Recessive Allele
feature that has different forms in a population g Hh
Genetic makeup of an organism
Chance that something may or may not happen
Used to predict possible traits of offspring
Instructions for our traits
Red hair
the two forms of a gene are given in
Physical appearance of an organism T
Different forms of a characteristic 12

13. Probability
The mathematical chance that something will happen is known as probability.
Genotype probability:
Pp x Pp cross has a 50% chance of receiving either allele from either parent.
The probability of inheriting two p alleles is ½x½, which equals ¼, or 25%.

14. Monohybrid vs. Dihybrid Punnett Square
A monohybrid Punnett square is one where only one trait is crossed.
Example: A tall pea plant TT is crosses with a short pea plant tt.
A dihybrid Punnett square is one where two traits are crossed.
Example: a tall, green flowered plant TtGg is crossed with a short, yellow flowered plant ttgg. T t Tt TG Tg tG tg
TtGg
Ttgg
ttGg

15. Rr x rr

16. RrYy x rryy

17. Blood Types Genotype Phenotype AA(ho) or AO(he) = BB(ho) or BO(he) =
AB =
OO =
*Ho = homozygous
*He = heterozygous
Phenotype A B AB O