The Work of Gregor Mendel

VOCAB Transmission of characteristics from parents to offspring = ____________ The science that studies heredity =_____________

The “father of genetics” is __________________, a monk whose study of genetic traits was the beginning of our understanding of how genes are passed on

Mendel designed experiments using __________in the monastery garden

A specific characteristic is called a _________ Mendel studied _________ in peas. Pearson Education Inc,; Publishing as Pearson Prentice Hall

MENDEL’S EXPERIMENTS ____ generation (_________) ____ generation (______= offspring) ___ generation

Go to Section: P Generation F 1 Generation F 2 Generation TallShortTall Short Section 11-1 Principles of Dominance

When Mendel ______________ PLANTS with 2 ______________ traits: (EX: Tall crossed with short) He always found same pattern: 1. ONLY ______ trait ____________ in the ____generation BUT ___________ trait ____________ in the ____ generation in a _________ ratio

PATTERNS ARE THE KEY Image modified from:

Mendel decided that there must be a __________________ that control each trait and that one factor must be able to _______ the other.

We now know that Mendel’s factors are ______ carried on ________________ _________________

Different choices for a gene are called ___________.

__________________ = An allele that ________ the presence of another allele __________________ = An allele that __________________ the presence of another allele

PROBABILITY & PUNNETT SQUARES 11-2

It can be written as a: Fraction ____ Percent ____ Ratio ____ The chance that an event will occur = ____________________

COIN FLIP There are 2 possible outcomes: HEADS TAILS capital The chance the coin will land on either one is: ____ ____ ____ Alleles segregate randomly just like a coin flip... So can use probability to predict outcomes of genetic crosses.

DOMINANT/RECESSIVE _____________ allele is represented by a ____________ letter. (usually the first letter of the trait) ____________ allele is represented by the SAME _________________ letter. EX: Tall = ______ Short =______

HOMOZYGOUS HETEROZYGOUS When both alleles in the pair are the SAME Ex: ____ or _____ ____________________= ________ When both alleles in the pair are different Ex: ______ ___________________ = ______________

PHENOTYPE/GENOTYPE The genetic makeup of an organism is its _____________ The appearance of an organism is its _____________

PUNNETT SQUARES are used to show possible offspring from a cross between 2 parents _______________ go at top and on left side Boxes show ____________ ___________________ T TtTt possible offspring combinations Parent alleles

Tall = T Round seeds = R Short = t Wrinkled seeds = r What’s the genotype? Homozygous short = ________ Heterozygous round = _____ Pure wrinkled = _____ Hybrid tall = _____

IN PEA PLANTS Tall is dominant over short TALL = ____ SHORT = ____ LET’S MAKE A CROSS! PURE TALL PURE SHORT X

PURE TALL parent What are the parent alleles?   What gametes can it make?

PURE SHORT parent What are the parent alleles?   What gametes can it make?

GENOTYPE _____ PHENOTYPE _______ _____ of the offspring ____ % ___/4 will be

HYBRID TALL parent What are the parent alleles? _________   What gametes can it make?

GENOTYPES ¼ = _____ ½ = _____ ¼ = _____ PHENOTYPES ____ or ____% _________ ____or ____% __________

PRACTICE MAKING GAMETES Tall = ____ Round seeds = ___ Short = ____ Wrinkled seeds = ___ T t R r

Homozygous Tall parent = What gametes can it produce? What are the possible gametes?  

PURE wrinkled parent = What gametes can it produce? What are the possible gametes?  

Heterozygous Round parent = What gametes can it produce? What are the possible gametes?  

Hybrid Tall parent = What gametes can it produce? What are the possible gametes?  