Question | Answer |
trait | the genetic make up of an organism |
gamete | a characteristic that can pass on to its offspring |
homozygous | organisms with two identical alleles for a particular trait |
heterozygous | an organism that has two different alleles for a trait (hybrid) |
punnett square | A tool that describes all the possible combinations of alleles that can results from a genetic cross. |
polygenic trait | governed by two or more genes. (Most traits i.e. skin and eye color) |
crossing over | The physical exchange leading to an intermediate phenotype |
nondisjunction | failure of the chromosomes to separate during anaphase of meiosis |
phenotype | physical characteristics of an organism, regardless of its genes |
genotype | the different forms of a gene; representation of genes by letters |
sex linked trait | Genes carried on the X chromosome. |
dominant | an allele whose trait always shows up |
recessive | trait that is masked when a dominant allele is present |
diploid | full set of chromosomes EX. 46 |
random assortment | chromosomes are sorted into daughter cells randomly |
fertilization | union of egg and sperm to form a zygote |
incomplete dominance | occurs when the phenotype of the offspring is somewhere in between the phenotypes of both parents, genes are expressed equally in a heterozygous |
co-dominant allele | both alleles are expressed in heterozygous individuals |
pedigree | Family tree showing inheritance of traits |
carrier | A person who has one recessive allele but does not have the trait |
haploid | a cell with only one copy of each chromosome, half EX 23 |
genetic variation | variations of genomes among individuals in a population. |
allele | the different forms of a gene |