Inquiry 11/19 and 11/20

• Please put your test corrections and test in the inbox (even if you didn’t finish)

• No warm-up! Flip to section 3 of your lab book

Learning Targets

I can correctly write the genotype and phenotype of an organism.

I can analyze and explain the results of dominant and recessive yeast traits.

Class Genetics Study(Leave room for a 4-5 sentence yeast lab conclusion)

Record your results as we go through the trials:Taster or non-tasterRoller or non-rollerAttached earlobes or free-hangingHitchhiker's thumb or notL over R or R over LMid-digital hair or noneRight or leftFreckles or none

Class Genetics StudyRecord Class Data

Taster or non-tasterRoller or non-rollerAttached earlobes or free-hangingHitchhiker's thumb or notL over R or R over LMid-digital hair or noneRight or leftFreckles or none

Class Genetics Study

1. Which traits that we studied are dominant?

Intro. to Genetics

How do the genes you

inherit make you “you”?

History of Genetics

Gregor Mendel 1822-1884 “Father of genetics” Austrian monk who studied inheritance

of physical traits in pea plants

Pea plants reproduce sexually- with male and female gametes Gametes = sperm (pollen) and eggs

Peas can self-pollinate and be true-breeding True-breeding: short plants breed short

plants and tall plants breed tall plants.

Mendel’s Pea Plant Study

Mendel’s Pea Plant Study

Mendel studied these traits

Mendel’s Crosses

Mendel bred plants with different traits and studied the offspring. original parents are

the P generation. offspring are the F1

(daughter/son) generation

Mendel’s Findings When crossing

parent plants (P) with different traits, all F1 plants looked the same!

When crossing F1 plants, three out of four offspring looked like the parents!

2 of Mendel’s Laws

Law of Inheritance Traits are controlled by pairs of genes-

with one gene coming from each parent These genes are called alleles

Law of Dominance some alleles are dominant and other

are recessive. Dominant – physically expressed Recessive – present but not expressed

Key Terms

Gene Sections of DNA within chromosomes Are the units of heredity

Allele Alternative genes for trait Example: Height (Tall or Short); Eyes

(Brown or Blue); Cheeks (Dimple or No Dimple); Hair Line (Peak or Straight)

Dominant vs. Recessive

Each gene has two possible alleles Dominant- always expressed Recessive- always hidden by a dominant

allele. Example: Dimpled chin (cleft chin) is

dominant D= dimpled d= non-dimpled Your two copies canbe DD, Dd, or dd

Dominant vs. Recessive

Genotype= the alleles that you have for a trait

Phenotype= the physical expression of those alleles

A person with a dimpled chin can have the genotype DD or Dd

A person with a non-dimpled chin can only have the genotype dd

More Definitions

Homozygous= two of same allele (DD or dd)

Heterozygous= two different alleles(Dd- also called hybrid)

Back to Class Genetics

Answer the rest of the questions from the worksheet IN YOUR LAB BOOK.

Yeast Lab

1. Briefly record under your prediction grid why you chose each color for each “baby”

Yeast Lab Results/Conclusion

Record the color of each offspring in each box.

Conclusion Claim- which color is dominant? Evidence- how do you know? Reasoning- why does being dominant or

recessive result in that color pattern?

Punnett Squares Knowing genotypes of parents, we can

predict the probability of offspring having dominant/recessive traits

R R

R RR RR

r Rr Rr

Results:

Genotypes:

50% RR; 50% Rr

Phenotypes:

100% round

Ex: Peas

Round seeds = R

Wrinkled seeds = r

Simple Punnett Self Test

In the Griffin Family, round heads are dominant to football shaped heads. Cross a parent who is homozygous dominant with one who is heterozygous. Show the genotypic and phenotypic ratios.

Mendel’s Laws Law of Segregation

During gamete formation two chromosomes separate

Each gamete contains oneallele for each trait

Law of Independent Assortment Traits are inherited independently of

each other