Genetics PEdegree 11-22 Flashcards
Basic unit of inheritance
Gene
The physical location of a gene on a chromosome
Locus
Alternative forms of a gene at a given locus
Allen
Genetic constitution of an individual
Genotype
Observed expression of a gene (physical manifestations); genotype plays a role (environment and other genes also play a role)
Phenotype
Identical alleles at a single locus
Homozygous
Different alleles at a single locus
Heterozygous
A condition seen in both the homozygous and the heterozygote; only on copy of the mutant allele is necessary for phenotypic expression
Dominant
A condition seen only in the homozygote; requires two copies of the mutant allele for phenotypic expression
Recessive
Are dominant and recessive about phenotype or genotype
Phenotypic expression
A nonsex chromosome
Humans have 22
Autosome
X or Y chromosome
Sex chromosome
Two copies of each chromosome
Diploid
All cells in the body except gamaetes
-always diploid
Somatic cells
Sperm or egg cells, always haploid
Gametes
What are the major types of genetic disease
- single gene disorders
- chromosome abnormalities
- multifactorial traits
Produced by the effect of a single gene (or gene pair), usually transmitted in simple patterns as autosomal dominant, autosomal recessive, or X linked
Single gene disorders
How are single gene disorders usually transmitted as?
- autosomal dominant
- autosomal recessive
- X linked
What are other names for single gene disorders
-mendelian disorders or monogenic disorders
Deviation from the normal chromosome number or structure
Chromosome abnormalities
Combined effects of multiple genetic and non genetic influences
Multifactorial traits
What is the most significant type of genetic disease in gene pool?
Single gene disorders
What is least likely to have serious consequences in pedigree?
Multifactorial traits
A disease or condition that is present at birth. Can be either hereditary or acquired
Congenital
