| A | B |
|---|
| recombination | the reassortment of genes or characters into different combinations from those of the parents |
| Meiosis | cellular reproduction from 1 cell, only in gametes |
| Genetics | study of heredity and heredity variation |
| Gene | a heritable factor that controls a specific characteristic |
| Chromosome | 1 DNA molecule coiled with proteins |
| Homologous Chromosome | a pair of Chromosomes with the same length, centromere location, and staining pattern |
| Karyotyping | a display of condensed chromosomes arranged in pairs; used to screen for abnormal number of chromosomes or defected chromosomes |
| Genotype | genetic make-up of an organism |
| Alleles | alternate versions of genes that account for variations in inherited characteristics |
| Phenotype | physical and physiological traits of an organism |
| Dominant allele | the allele that is fully expressed in the phenotype |
| Recessive allele | the allele that is completely masked in the phenotype |
| Co-Dominant allele | a phenotype situation in which the 2 alleles affect the phenotype in separate distinguishable ways |
| Locus | a particular place along the length of a certain chromosome where a given gene is located |
| Homozygous | Having 2 identical alleles for a given trait |
| Heterozygous | Having 2 different alleles for a given trait |
| Carrier | individual is heterozygous at given genetic locus with 1 normal alleles and 2 potentially harmful recessive allele. The heterozygote is phenotypically normal for the character determined by the gene but can pass on the harmful allele to an offspring |
| Test cross | breeding of an organism of unknown genotype with a homozygous recessive individual to determine the unknown genotype |
| Punnett Square | diagram used in the study of inheritance to show the results of random fertilization |
| Pedigree | tree describing the occurrence of heritable characters in parents and offspring across as many generations as possible |
| Genetic Variation | movement of chromosomes during meiosis |
| Non-disjunction | leads to change in chromosome number (ex: down syndrome) |
| Mendel’s Laws of Independent assortment | each pair of alleles segregates independently of the other pairs of alleles during gamete formation |
| Mendel’s Law of segregation | 2 alleles separate during meiosis and end up in different gametes |
| Genetic screening | testing for the absence of certain genes |
| Polygenetic Inheritance | additive effect of 2 or more genes on a simple phenotype characteristic (ex: skin color) |
| Linkage groups/genes | genes located on the same chromosome that tend to be inherited together on genetic crosses |
| Sex linkage genes | when a gene is found on 1 of the sex chromosomes (ex: color blindness) |
| Meiosis stages | interphase, prophase 1, metaphase1, anaphase1, telophase1/cytokinesis/// prophase2, metaphase2, anaphase2, telophase2/cytokinesis2 |
| Chiasmata | occurs during prophase 2, homologous chromatids that have exchanged genetic material through crossing over |
| Sex chromosomes | one of the pair of chromosomes responsible for determining the sex of an individual |
| Autosome | a chromosome that is not directly involved in determining sex |
