Mind Map of Mendelian Genetics - Heredity Part II

Mendelian genetics - Heredity Part IIIntroduction to heredityHereditary traits and GeneticsMonohybrid Inheritancegenea section of dna at a specific location on the chromosomecontains information that determines a traitmendelian traitsingle trait determined by 1 genesomatic cellany cell in the body apartfrom gametesGameteSex cellhereditary trait characteristic that can bepassed on from one generation to anotherexamples:wet or dry earwaxattached / detached earlobeskin colourhair coloureye colourblood typeface shapechin shapeability to roll tongueinheritance of 1 characteristic with2 contrasting forms controlled by a single geneeach gene is made up of a pair of allelesalleles can be dominant or recessivehomologous chromosomesexist in pairs whereone chromosome comes from the male parentone chromosome comes from the female parentboth have the exactsame gene locigeneunit of inheritance found on a particular locus of a chromosomesmall portion of DNA in a chromosome that controlsa particular characteristic or protein in an organismallelesalternative version of a gene that occupy thesame locus on a pair of homologous chromosomesPhenotypetraits of an organism that can be seeninfluences by genotype + environmentGenotypegenetic make-up of an organism that isinherited from its parentsHomozygous organism (for a certain trait)happens if the 2 alleles controllingthe trait are the samepossible combinations:homozygous dominant (TT)homozygous recessive (tt)Heterozygous organism (for a certain trait)happens if the 2 alleles controllingthe trait are not the samepossible combination: Ttcan exist in 2 forms:dominantrecessivedominant allele will express itself inboth homozygous dominant and heterozygous conditionsrecessive allele will only express itselfin a homozygous recessive genotypeMendel's Monohybrid ExperimentMendel cross-bred pure-bred Tall pea plantswith pure-bred dwarf plantsF1 Generation hybrids allturned out to be tall plantsAfter the F1 offspring self -fertilized and produced seeds,F2 Generation plants came upRatio of tall plants to dwarf plants: 3 : 1(approx)why?genes are responsible for thiseach charactersitic is controlled bya pair of factors in the cellsIf the 2 factors are different, only thedominant factor will express itselfGenetic modelscan be used to explain how allelesare passed on to offspringpredict the traits that will be displayed by the offspringboth the tall and short plants are pure bredhowever, only the tall alleles were dominantand the short alleles were recessiveso when the 2 dominant tall gametes fused withthe 2 recessive short gametes, the dominant alleleswere expressed this resulted in 1 dwarf and 3 tall hybrid plants