DEFINITIONS Flashcards
Genotype
The genetic composition of an organism, all the alleles that it contains.
Mutation
A change to the structure or quantity of the sequence of bases in DNA. (can be inherited if in gamete formation)
Phenotype
Expression/appearance due to genotype and environment.
Modification
A change to the phenotype that does not affect the genotype (uninheritable).
Gene
Section of DNA on a chromosome, codes for a particular polypeptide, determines single characteristic.
Locus
Position of a gene on a chromosome.
Allele
One of the different forms of a gene
Heterozygous
2 alleles different
Homozygous
2 alleles same
Dominant allele
Always expressed in the phenotype
Recessive allele
Only expressed in the phenotype when recessive
Co-dominant alleles
Both alleles are expressed in the phenotype
Monohybrid inheritance
The inheritance of a single gene
Sex-linked gene
Any gene carried on the X or Y chromosome.
Carrier
An individual who carries the allele without it being expressed in their phenotype