Warm ups:

1. What do I mean if I say I “INHERITED” my green eyes from my mother?

2. Give examples of some “TRAITS” that you inherited from your parents….

Word Definition Picture

1. Alleles

Two forms of a gene (one from

mother, one from father)

Examples:

Height – short and tall

Hair – straight or curly

Tail – long or short

Word Definition Picture

2. Dominant

Gene

The strong form of the gene

(you ALWAYS see it)

Written as: Capital Letter

Word Definition Picture

3. Recessive

Gene

The weak form of the gene

(NOT always seen)

Written as a lowercase

 DOMINANT AND RECESSIVE TRAITSTraits in the left-hand column dominate over those listed in the right-hand column.

Dominant Traits

Recessive Traits

Eye coloring

Brown eyes Gray, green, hazel Blue

Grey, green, hazel,blue eyes Blue Albino (pink)

Vision Farsightedness Normal vision Normal sight Normal color vision

Normal vision Nearsightedness Night vision Color blindness

Hair Dark hair Non-red hair (blonde, brunette) Curly hair Full head of hair Widow's peak hairline

Blonde hair, light hair Red hair Straight hair Baldness Normal hairline

PracticeB = brown eyes b = blue eyesC = curly hair c = straight hair

1. What is the symbol (letter) for someone who has brown eyes?

2. What is the symbol for someone who has straight hair?

3. What is the symbol for someone who has blue eyes?

4. A capital letter represents ?

B

c

bDominant gene or trait

PracticeG = green plant g = yellow plantT = tall plant t = short plant

1. What is the symbol a plant that is green?2. What is the symbol for a plant that is short? 3. What is the symbol for a plant that is yellow?4. A lowercase letter represents ?

Gt

g

Recessive gene or trait

Using symbols in genetics

1. Use letters to represent genes

2. Always have two letters – 2 genes for each trait

Word Definition Picture

4. Purebred or Homozygous

Having the same two

Always two Dominants or

two recessives

BB or bb

Word Definition Picture

5. Hybrid – “mutt” or Heterozygous

Having two different alleles

Always a Dominant and a

recessive

Bb

Purebreds vs. Hybrids Practice

Examples:a. Two dominant tall genes ---

b. Two recessive short genes ---

c. One dominant and one recessive ---

TTtt

Tt

Homozygous Heterozygous

Hybrid and Purebred Practice problems

T = tall t = shortG = green g = yellow

1. A plant is purebred tall. What genes does it have?

2. A plant is hybrid green. What genes does it have?

3. A plant is purebred yellow. What genes does it have?

gg

Gg

TT

Hybrid and Purebred Practice problems

B = brown b = blue C = curly c = straight

1. A dog is purebred with brown eyes. What genes does it have?

2. A person is hybrid with curly hair. What genes does he have?

3. A dog has blue eyes. What genes does it have?

bb

Cc

BB

Word Definition Picture

6. Genotype

Genes written in letter symbols that show possible traits.

Physical vs. Actual

Word Definition Picture

7. Phenotype

An organism’s inherited appearance. (What physically shows.)

Phenotype and Genotype Practice Problems

T = tall t = short

1. What is the phenotype for a person who is tall?

2. What is the genotype for a person who is short?

3. What is the phenotype for a person who is short?

4. What is the genotype for a person who is tall?

The relationship between the genotype and phenotype is a simple one ...

The genotype codes for the phenotype!                    

Sum it all up!

• Traits from an organism pass from the parents to the offspring.

• Gene pairs determine traits.• Organisms inherit genes in PAIRS. One

from each parent.• Genes are dominant and recessive.

(When the two go a walking, the capital does the talking! Hybrid)

Exit slip: Five finger summary!

Take out a piece of paper. Trace your hand on the paper and write genetics in your palm. List five things that you learned from today’s lesson and write them in each of your five digits.