Mendel and the Gene Idea
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| 3441664073 | Character | heritable feature that varies among individuals | 0 | |
| 3441664074 | Trait | every variant for a character | 1 | |
| 3441668795 | True Breeding | -varieties over many generations -produced only same variety as parent | 2 | |
| 3441670028 | Hybridization | mating/crossing of 2 true-breeding varieties | 3 | |
| 3441672850 | P Generation | -parental generation -true breeding parents | 4 | |
| 3441674178 | F1 Generation | -first filial generation -hybrid offspring of P generation | 5 | |
| 3441676928 | F2 Generation | -second filial generation -offspring of F1 hybrids w/ self pollination | 6 | |
| 3441678706 | Alleles | -alternative versions of genes -DNA variations possible for gene at particular locus | 7 | |
| 3441681057 | Dominant Allele | determines organism's appearance | 8 | |
| 3441687230 | Recessive Allele | has no noticeable effect on organism's appearance | 9 | |
| 3441688222 | 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 | 10 | |
| 3441702161 | Punnett Square | diagrammatic device for predicting the allele composition of offspring from a cross between individuals of known genetic makeup | 11 | |
| 3441709844 | Homozygous | pair of identical alleles for a character of a gene (PP, pp) | 12 | |
| 3441711748 | Heterozygous | -pair of different alleles for a character of a gene (Pp) -not true-breeding b/c produces gametes w/ different alleles | 13 | |
| 3441715515 | Phenotype | organism's appearance or observable traits | 14 | |
| 3441718420 | Genotype | organism's genetic makeup | 15 | |
| 3441718421 | Testcross | -breeding an organism of unknown genotype w/ recessive homozygote -can reveal genotype of organism | 16 | |
| 3441721652 | Monohybrid | -progeny produced by crossing different true-breeding parents -heterozygous for one character | 17 | |
| 3441728878 | 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 | 18 | |
| 3441739395 | Complete Dominance | -offspring always looks like one of 2 parental varieties -phenotypes of homozygous dominant and heterozygous indistinguishable | 19 | |
| 3441742210 | Incomplete Dominance | -neither allele of gene complete dominant, F1 hybrids have phenotype in between 2 parents -ex. red flower x white flower = pink flower | 20 | |
| 3441748925 | Codominance | -2 alleles of gene both affect phenotype in separate, distinguishable ways -ex. red flower x white flower = red & white flower | 21 | |
| 3441754805 | 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 in few years -only inherited by children w/ 2 copies of Tay-Sachs allele (homozygotes) -organismal level: allele recessive -biochemical level: incomplete dominance (activity level of lipid-metabolizing enzyme=intermediate) -molecular level: codominance (heterozygous individuals produce equal normal and dysfunctional enzymes) | 22 | |
| 3441779389 | Pleiotropy | -property where genes have multiple phenotypic effects -ex. alleles responsible for many symptoms associated w/ hereditary diseases (cystic fibrosis, sickle-cell) |  | 23 |
| 3441790994 | Epistasis | -gene in one locus alters phenotypic expression of gene at second locus -ex. one allele codes for skin color, another codes for pigmentation deposit-if pigmentation allele recessive, organism will be white (albino) despite skin color allele) |  | 24 |
| 3441793919 | Quantitative Characters | characters that vary in a population along a continuum (in graduations) | 25 | |
| 3441795385 | Polygenic Inheritance | -an additive effect of 2+ genes of a single phenotypic character -ex. skin color |  | 26 |
| 3441813901 | Norm of Reaction | phenotypic range for genotypes of organisms | 27 | |
| 3441815826 | Multifactorial | many factors (genetic and environmental) influence phenotype | 28 | |
| 3441817065 | 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 | 29 | |
| 3441821813 | Carriers | heterozygotes who could transmit recessive allele to offspring | 30 | |
| 3441826639 | 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 -pleiotropic effects | 31 | |
| 3441840637 | Sickle-Cell Disease | -caused by substitution of single amino acid in hemoglobin -molecules aggregate into long rods-deform RBC into sickle shape under low oxygen concentration -heterozygotes w/ trait healthy, but suffer many symptoms -organismal level: normal allele incompletely dominant to sickle cell allele -molecular level: 2 alleles codominant | 32 | |
| 3441855095 | Achondroplasia | -form of dwarfism -trait for which recessive allele more prevalent than corresponding dominant allele -dominant alleles cause lethal disease less common than recessive alleles -all lethal alleles arise by mutations in gametes -if offspring dies, dominant allele not passed | 33 | |
| 3441864136 | 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 | 34 | |
| 3441875052 | Amniocentesis | -needle entered into uterus, 10 mL of amniotic fluid extracted -14th-16th week of pregnancy -some disorders detected from presence of certain chemicals of fluid -test for others performed on cell cultures (descendants of fetal cells in amniotic fluid) -used for karyotyping to identify chromosome defects | 35 | |
| 3441882558 | 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) -imaging techniques spot anatomical abnormalities | 36 | |
| 3441890918 | Phenylketonuria (PKU) | recessively inherited disorder where children can't properly metabolize phenylalanine (amino acid) -> mental retardation due to build up | 37 |
