Mendel and the Gene Idea
5339551842 | Trait | every variant for a character | 0 | |
5339551845 | P Generation | -parental generation -true breeding parents | 1 | |
5339551846 | F1 Generation | -first filial generation -hybrid offspring of P generation | 2 | |
5339551847 | F2 Generation | -second filial generation -offspring of F1 hybrids w/ self pollination | 3 | |
5339551848 | Alleles | -alternative versions of genes -DNA variations possible for gene at particular locus | 4 | |
5339551849 | Dominant Allele | determines organism's appearance if present | 5 | |
5339551850 | Recessive Allele | has no noticeable effect on organism's appearance if dominant is there, only shows up when 2 are present | 6 | |
5339551851 | Law of Segregation | df: the 2 alleles for a heritable character segregate (separate) during gamete formation and end up in different gametes -egg/sperm gets 1/2 alleles present in somatic cells of organism making gamete -segregation corresponds to distribution of 2 members of homologous pair of chromosomes to different gametes in meiosis | 7 | |
5339551852 | Punnett Square | diagrammatic device for predicting the allele composition of offspring from a cross between individuals of known genetic makeup | 8 | |
5339551853 | Homozygous | pair of identical alleles for a character of a gene (PP, pp) | 9 | |
5339551854 | Heterozygous | -pair of different alleles for a character of a gene (Pp) -not true-breeding b/c produces gametes w/ different alleles | 10 | |
5339551855 | Phenotype | organism's appearance or observable traits | 11 | |
5339551856 | Genotype | organism's genetic makeup | 12 | |
5339551857 | Testcross | -breeding an organism of unknown genotype w/ recessive homozygote -can reveal genotype of organism | 13 | |
5339551858 | Monohybrid | -progeny produced by crossing parents of one trait | 14 | |
5339551859 | Law of Independent Assortment | -each pair of alleles segregates independently of other pair of alleles during gamete formation -only applies to genes located on different chromosomes | 15 | |
5339551860 | Complete Dominance | -offspring always looks like one of 2 parental varieties -phenotypes of homozygous dominant and heterozygous indistinguishable | 16 | |
5339551861 | Incomplete Dominance | -neither allele of gene complete dominant, F1 hybrids have phenotype in between 2 parents -ex. red flower x white flower = pink flower | 17 | |
5339551862 | Codominance | -2 alleles of gene both affect phenotype in separate, distinguishable ways AB blood type | 18 | |
5339551863 | Tay-Sachs Disease | -inherited disorder of alleles depends on level at which phenotype observed lipids b/c crucial enzyme doesn't work -> accumulation of lipids -causes seizures, blindness, degeneration of motor and mental performance, dies in a few years -allele recessive | 19 | |
5339551867 | Polygenic Inheritance | -an additive effect of 2+ genes of a single phenotypic character -ex. skin color, height | ![]() | 20 |
5339551870 | Pedigree | -family tree describing traits of parents and children across generations -helps calculate probability that child will have particular genotype and phenotype, if child could inherit some genetic disease | 21 | |
5339551871 | Carriers | heterozygotes who could transmit recessive allele to offspring | 22 | |
5339551872 | Cystic Fibrosis | -results in abnormally high concentration of EC chloride -> mucus in lungs to be thicker and stickier -> builds up in pancreas, lungs, digestive tract, and other organs Recessive disease, passed by carrier parents | 23 | |
5339551873 | Sickle-Cell Disease | -caused by substitution of single amino acid in hemoglobin -molecules aggregate into long rods-deformed Red Blood Cells into sickle shape under low oxygen concentration -heterozygotes w/ trait healthy, but suffer many symptoms, codominance seen | 24 | |
5339551874 | Achondroplasia | -form of dwarfism, dominant - 2 dominant alleles cause lethal disease less common than recessive alleles | 25 | |
5339551875 | Huntington's Disease | -dominant alleles can escape elimination if it causes death after carrier reaches advanced age -when symptoms arise, disease may have already been passed to offspring (50/50) -causes degradation of nervous system -by analyzing DNA samples from large family w/ high incidence of disorder -genetics track allele to locus near tip of chromosome for gene sequences | 26 | |
5339551876 | Amniocentesis | -needle entered into uterus, -14th-16th week of pregnancy -used for karyotyping to identify chromosome defects | 27 | |
5339551877 | Chronic Villus Sampling (CVS) | -narrow tube inserted through cervix into uterus and tissue sample from placenta sucked out -8th-10th week of pregnancy -cells of CV of placenta have same genotype as fetus -proliferated for karyotyping (advantage over amnio) | 28 | |
5339551878 | Phenylketonuria (PKU) | recessively inherited disorder where children can't properly metabolize phenylalanine (amino acid) -> mental retardation due to build up | 29 |