Homozygous
having identical alleles at corresponding chromosomal loci
Heterozygous
having dissimilar alleles at corresponding chromosomal loci
Dominant
These traits always are expressed
Recessive
These traits are only expressed when homozygous
Genotype
genetic makeup of an organism
Phenotype
what an organism looks like as a consequence of its genotype
Gregor Mendel
father of genetics
Rats
What did Gregor Mendel first try experimenting on
Austrian
What was Gregor Mendel's nationality
Farmers
What was Gregor Mendel parent's occupation
Allele
one of a number of different forms of a gene
Homologus
Two different chromosomes with different forms of information (not identical; contain different information for the same trait)
Diploid
In genetics, everything is almost always what?
Trait
a genetically determined variant of a characteristic
Characteristic
An attribute of an organism, such as hair color, height, color pattern, etc.
Sex Influenced
description of a trait that is caused by a gene whose expression differs in males and females
tetrad formation
In Meiosis, each homologous chromosome pair becomes 2 pairs of joined chromatids lying side by side.
Nondisjunction
meiosis in which there is a failure of paired homologous chromosomes to separate
placenta
the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus
Penetrance
The percentage of individuals with a particular genotype that actually displays the phenotype associated with the genotype.
Expressivity
the degree to which a genotype is expressed in an individual
Pleiotropy
A single gene having multiple effects on an individuals phenotype
Imprinting
Makes the difference of who contributes the allele
X-inactivation
Where part of the x deactivates