Genetics Chromosome Number Fruit fly example: 8 chromosomes total __ came from male parent __ came from female parent

Genetics Homologous chromosomes- paired chromosomes having genes for the same ____ located at the same _____ on the chromosome ______- having two of each kind of chromosome (__); normal body cells Diploid cells have two complete sets of chromosomes/two complete set of genes

Genetics Gametes (sex cells) of sexually reproducing organisms have only a _____ set of chromosomes _______- having one of each kind of chromosome (__) Fruit fly gametes would be n = 4

Genetics The Work of Gregor Mendel ________- scientific study of heredity _______ ______- Austrian monk who experimented using pea plants Determined rules of inheritance ____________- joining of male & female gametes to form single cell

Genetics Genes & Dominance Studied 7 different pea plant ____ _____- a characteristic that can be passed on to offspring For each trait, studied a contrasting character: Ex. _____ _____- green or yellow

Genetics Original pair of plants = __ generation Offspring = __ generation _______- offspring of parents that have different forms of a trait Results? Every offspring had a character of ____ ____of the parents

Chapter 11- Genetics Two conclusions: Inheritance determined by ______ passed from one generation to the next ____- the functional units of inheritance Each trait controlled by ___ gene with ___ contrasting forms _______- alternate forms of a gene

Genetics Second conclusion called the principle of __________: Some alleles are _______ and others are ________ ________- an allele of a gene that is always expressed (__) _________- an allele of a gene that is expressed only when the dominant allele is not present (__)

Genetics Segregation What had happened to _________ alleles (traits) in plants? Mendel allowed __ plants to self-pollinate Produced __ generation which showed recessive trait in 1 out of 4 plants (__ ratio)

Genetics Dominant allele ________ recessive trait in F1 generation Reappearance in F2 generation showed that at some point alleles became ________ Mendel suggested that they _________ from one another during ______ formation

Genetics Law of Segregation- states that every individual has ____ alleles of every gene; when gametes are produced, each gamete receives ____ of these alleles

Genetics Probability & Punnett Squares Every time Mendel repeated a particular cross, he obtained _________ results ¾ plants showed ________ trait; ¼ showed ________ trait Mendel realized that __________ could be used to explain results

Genetics Genetics & Probability __________- the likelihood that a particular event will occur Two possible outcomes for a coin flip: heads or tails Probability of each occurring is _____ Chance of heads is 1 in 2, or ____

Genetics Chance of heads coming up three in a row? Each flip is an ______________ event: Probability of three heads in a row- ½ x ½ x ½ = ____ Way alleles segregate is _______, like a coin flip Principles of probability can be used to ________ outcomes of genetic crosses

Genetics Punnett Squares Gene combinations from a given cross can be determined using a ________ ______ Letters in Punnett square represent ______ ________ from each parent are shown along one side and the top of the square Used to _______ and _______ genetic variations resulting from a cross

Genetics __________- if an organisms two alleles for a trait are the same Can be homozygous dominant (__) or homozygous recessive (__) _____________- when the two alleles for the same trait are different (__) Homozygous = ________ for trait Heterozygous = ________ for trait

Genetics __________- the physical expression of the genes; how the trait looks Ex.- Tall; short; yellow seeds; green seeds _________- allele combination that an organism contains TT; Tt; tt

Genetics Probability & Segregation Probability predicts that if the alleles _________, then a ___ phenotypic ratio should be seen Each cross showed a 3:1 ratio Mendel’s law of segregation proven correct

Genetics Since probabilities predict __________: the larger the number of __________, the closer the _____ comes to the probability

Genetics Exploring Mendelian Genetics Mendel further investigated: Alleles segregate- but do alleles _________ together? or are they __________ of one another?

Genetics Independent Assortment Mendel followed two _________ genes through two generations Crossed purebred plants for seed _____ and seed ______ Round, yellow seeds (____) with Wrinkled, green seeds (____)

Genetics Only provided hybrid plants needed for next cross All F1 plants had genotype ____ F2 generation showed ___ plants that had phenotypes not found in the ________ So… Alleles for different traits segregate ___________ of one another

Genetics Summary of Mendel’s Principles Inheritance is determined by individual units called ______. Genes passed from _______ to ________. When two or more forms (_______) of a gene exist, some forms may be ________, others _________.

Genetics In most sexually reproducing organisms, each adult has ___ copies of each gene – one from each parent. These copies are _________ from one another during ______ (gamete formation) Alleles for _________ genes usually segregate ___________ of one another

Genetics Complex patterns of Inheritance Important exceptions to Mendel’s principles Some alleles are _______ dominant nor recessive Many traits controlled by ________ alleles, or multiple genes

Genetics Incomplete dominance Appearance of a ______ phenotype Due to one allele being not completely _________ over another 3rd phenotype somewhere __ ________ the two homozygous phenotypes

Genetics Codominance Expression of _____ alleles (ex. White bull crossed with a red cow yields a roan calf) Both alleles contribute to the __________

Genetics Multiple phenotypes from multiple alleles More common for multiple alleles to control a trait in a __________ Only two alleles of a gene can exist within the _______ Multiple ______ for a single _____ can be found within a population Examples: _____ _____- A, B, o ______ _____ ____- C, cch, ch, c

Genetics Polygenic Inheritance Traits that are determined through expression of ___ ___ _____ genes Polygenic traits show wide _____ of phenotypes Ex- _________, __________, _______

Genetics Genetics & the Environment Characteristics of any organism not solely determined by ______ Determined by interaction between genes and _________ Genes provide ____, how plan goes also depends on ___________