InheritanceChromosome: single molecule of DNA w/ many genes and associated proteinsHomologous chromosomes – same genes but different allelesDiploid – (2n), 2 full sets of chromosomesHaploid – (n), single sets of chromosomesGenotype – genetic makeup of an individual, what alleles they havePhenotype – an individual’s observed propertiesMonohybrid crosses:- Mendel started with a parental generation of homozygous plants w/ yellow (XX – dominant) and green seeds (yy – recessive)Outcomes:- In the first generation (F1) he recorded only yellow seeded plants, the genotype of those plants was Yy (heterozygous dominant)- In the second generation, (F2), heterozygous dominant (Yy) plants from the F1 generation obtained phenotypes of ratio 3 yellows to 1 green- Traits are coded by some kind of inheritable particle which he called ‘factors’ (genes)- Genes are transmitted as independent entities from one generation to another- Different versions of genes (alleles) and every individual has 2 copies- 2 alleles that the parent has are separated into different cells when gametes (sex cells) are formedLaw of SegregationMeiosis:- 2 alleles of each gene are packaged into separate gametes- segregate during gemete formation- during meiosis 1, homologous pairs of chromosomes separateExample/Case study: Cystic Fibrosis- abnormal transport of Cl2 and Na across an epithelium affected people unable to clear mucus from lungs- caused by mutation- homozygous recessive condition-Law of Independent AssortmentMeiosis:- during gamete function, segregation of alleles for one gene does not influence alleles for another gene only if genes are on different chromosomes- Ex: pink can yield either white or redInheritance: co dominance- 2 different alleles are being expressed together (but not as intermediate phenotypes like inincomplete dominance)BLOOD TYPE CHARTReceiver Receiver Receiver Universal ReceiverUniversal donorO A B ABDonors O Y Y Y YDonors A N Y N YDonors B N N Y Ydonors AB n N n YInheritance: Sex DeterminationX and Y-chromosomes determine sex in humansFemales: XXMales: XYHuntingtons, cystic fibrosis, and others found on genes that are autosomes and affect both sexes equally, while red-green color blindness, hemophilia, are found on sex chromosomes and mainly affect one sex (Called sex-linked)Some traits carried only on X/Y or recessive/dominant; so first identify the sex and sex chromosomesX inactivation- in female somatic cells, 1 x chromosome is active random shut off of 1 X-chromosome becomes inactiveRh factor- most important blood type characterization after ABO- Rh factor – additional antigens produced on red blood cells- Inherited autosomally (alleles are on chromosome
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