Genetics Vocabulary Self-Pollination- When ______________ from a plant ______________________ an egg from the same plant (this is how pea plants normally reproduce.)
Genetics Vocabulary Cross-pollination- produces _______________ that are the offspring of two different plants . Pollen from one plant is dusted onto the ____________ of another. This allow scientists to manipulate which plants reproduce together.
Genetics Vocabulary True-breeding- if allowed to self- pollination ______________ peas would produce offspring ______________ to themselves. Tall pea plants only reproduce with tall for many generations
Genetics Vocabulary Alleles- Different forms of a _______________________ <ul><li>2 different alleles for a gene in a pea plant </li></ul><ul><li>Tall or short </li></ul><ul><li>Yellow or green </li></ul>
Genetics Vocabulary Dominant – the alleles that are “________________” than others In Pea Plants Tall is Dominant to short.
Genetics Vocabulary Recessive – the ________________ form of a gene In Pea Plants Only shows up if two are present. Short + short = short.
Genetics Vocabulary Punnett Square – a diagram used to determine the ____________________ of offspring from a particular cross. T = Tall t = short
Genetics Vocabulary Phenotype – the physical characteristics of an organism TALL YELLOW BLUE EYES RED HAIR PINK PETALS
Genetics Vocabulary Genotype – what an organism genetic makeup looks like TT GG Tt gg YY
Genetics Vocabulary Homozygous – has two of the same alleles. TT GG tt gg YY
Gregor Mendel <ul><li>Gregor Mendel, a monk in the Czech Republic, is considered the "Father of Genetics", based upon experiments he conducted using garden peas. He helped lay down the principles of modern genetics. </li></ul>
Mendel’s Experiments <ul><li>Mendel was given a garden of pure bred pea plants. </li></ul><ul><li>He studied various traits in pea plants </li></ul>
The First Generation Cross (f 1 ) Mendel Crossed a purebred tall with a purebred short plant and got all tall plants! Step one = Define the Parents Genotype and Phenotype X Tall Short Phenotype = Genotype = TT X tt
The First Generation Cross (f 1 ) Step two = Set up the punnett square T T t t Mendel Crossed a purebred tall with a purebred short plant and got all tall plants! Phenotype = Genotype = Short X Tall Phenotype Genotype TT X tt
The Second Generation Cross (f 2 ) Mendel Crossed a two heterozygous Tall pea plants Step one = Define the Parents Genotype and Phenotype X Tall Tall Phenotype = Genotype = Tt X Tt
The Second Generation Cross (f 2 ) Step two = Set up the punnett square T t T t Mendel Crossed a purebred tall with a purebred short plant and got all tall plants! Phenotype = Genotype = Tall X Tall Phenotype Genotype Tt X Tt
Review Mendel’s Conclusions <ul><li>The factors that control heredity are individual units known as genes. In organisms that reproduce _________________, genes are inherited from each parent. </li></ul><ul><li>In cases in which two or more forms of the gene for a single ___________ exist, some forms of the gene may be dominant and the other may be recessive. </li></ul><ul><li>The two form of each gene are segregated during the formation of reproductive cells. </li></ul><ul><li>Two genes for different traits may ___________ _____________________ of one another. </li></ul>
Sample Problem #1 A yellow pod plant is crossed with a heterozygous pod plant. What is the genotype and phenotype of the offspring?
Sample Problem #2 A white flower pea plant is crossed with a homozygous recessive flower plant. What are the genotype and phenotypes of the offspring?
Sample Problem #3 A heterozygous tall plant is crossed with a homozygous tall plant. What is the genotype and phenotypes of the offspring.
Sample Problem #4 A color point cat is crossed with a heterozygous normal cat. What are the expected genotypes and phenotypes of their offspring?
Sample Problem #5 A homozygous tabby cat is crossed with a stripeless cat. What are the expected genotypes and phenotypes of their offspring?
Sample Problem #6 A heterozygous short haired cat is crossed with another heterozyogous cat cat. What are the expected genotypes and phenotypes of their offspring?
Trait Number of Students Demonstrat- ing Dominant Phenotype Number of Students Demonstrat- ing Recessive Phenotype Percentage Demonstrat- ing Dominant Phenotype Percentage Demonstrat- ing Recessive Phenotype Dominant Recessive Tongue Roller ( R ) Nonroller ( r ) Taster ( T ) Non-Taster ( t ) Free Earlobes ( E ) Attached Earlobes ( e ) Dimples ( D ) No Dimples ( d ) No 2 nd joint finger hair ( F ) 2 nd joint finger Hair ( f )
Two Trait Cross Mendel determined that alleles assort independently from each other, even when multiple traits are studied. Phenotype= 9:3:3:1 Genotype = 1:2:1:2:4:2:1:2:1
The British Royal Family Human traits are difficult to study for several reasons. Unlike some organisms, which produce slowly and only a few offspring at one time. Thus human traits must be studied through population sampling and pedigree analysis. A pedigree is a diagram that shows the phenotype of different generations. Royal family tree
Pedigree for ColorBlindness – a sex linked trait