What is a gene ?
sequence of bases on a DNA molecule that codes for a protein which results in a characteristic
What are alleles ?
One or more versions of a gene
What differs between each allele?
What are diploid organisms ?
ones that have 2 copies of each chromosome
Give an example of a diploid organism ?
What are haploid organisms ?
Ones that only have one allele for each gene
Give an example of a haploid organism ?
What is the locus?
Position of a gene on a chromosome
What is a genotype ?
Genetic constitution of an organism
represents pair of alleles for a characteristic
What is a phenotype ?
Expression of genetic constitution + its interaction with the environment
What are dominant allele ?
Ones that are always expressed in the organisms phenotype
What are recessive alleles ?
One that are only expressed in the homozygous recessive genotype/condition
What are codominant allele ?
Neither one is recessive so they are both expressed in the phenotype
When an organisms carries 2 copies of the same allele
When an organism carries 2 different alleles for a gene
What is monohybrid inheritance ?
Inheritance of a characteristic controlled by a single gene
What is meant by co dominance ?
Both alleles are expressed in the phenotype, and neither one is recessive
What is meant by multiple alleles ?
When there is more than two alleles of the same gene
What are dihybrid crosses ?
Show the likelihood of offspring inheriting certain combinations of the two characteristics from particular parents
What is dihybrid inheritance ?
Inheritance of 2 characteristics, which are controlled by different genes
What is the ratio for a dihybrid cross with 2 heterozygous parents ?