Heredity
is the passing of traits from parent to offspring
allele
different forms a gene may have for a trait
genetics
the study of how traits are inherited through the actions of alleles
dominant
Mendel called the tall height form that appeared because it dominated or covered up the short height form
recessive
the form that seemed to disappear.
Punnett square
a handy tool used to predict results in Mendelian genetics. Dominant and recessive alleles are represented by letters. A captial letter stands for a dominant allele and a small letter stands for the recessive gene
genotype
the genetic makeup of an organism
homozygous
an organism with two alleles for a trait that are exactly the same. This would be written as TT or tt
heterozygous
an organism that has two different alleles for a trait. The condition would be written as Tt
Phenotype
The physical trait that shows as a result of a particular genotype
incomplete dominance
is the production of a phenoytype taht is intermediate to those of the two homozygous parents
multiple alleles
a trait that is controled by more than two alleles is one considered to be controlled. Ex. human blood type: A, B, and O.
polygenic inheritance
occurs when a group of gene pairs act together to produce a single trait.
sex-linked gene
an allele inherited on a sex chromosome. ex. color blind, hemophilia
pedigree
a tool for tracing the occurrence of a trait in a family
genetic engineering
scientists are experimienting with biological and chemical methods to change the DNA sequence taht makes up a gene. It is used to help produce large quantities.
genome
the resulting chromosome map representing all of the human genetic material which is a chart taht shows the location of individual genes on a chromosome.