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-taster  Roller or non-roller  Attached earlobes or free-hanging  Hitchhiker's thumb or not  L over R or R over L  Mid-digital hair or none  Right or left  Freckles or none

Class Genetics Study Record Class Data  Taster or non-taster  Roller or non-roller  Attached earlobes or free-hanging  Hitchhiker's thumb or not  L over R or R over L  Mid-digital hair or none  Right or left  Freckles 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 “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 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 can be 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 RR RRR rRr 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 one allele for each trait  Law of Independent Assortment Traits are inherited independently of each other