6.1 - Mendelian Genetics

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., Aa, DD, bB, yy).

Front

What is the phenotype of an organism?

Back

The phenotype is the observable physical or biochemical characteristics of an organism, determined by its genotype.

Front

What does it mean for an allele to be dominant?

Back

A dominant allele is one that expresses its trait in the phenotype even when only one copy is present (e.g., B in Bb).

Front

What is the expected phenotype ratio from a BbTt x BBtt cross?

Back

The expected phenotype ratio is 1:1 for black fur and long tails to brown fur and long tails.

Front

In a Punnett square, what does each box represent?

Back

Each box in a Punnett square represents a possible genotype of the offspring resulting from the combination of parental alleles.

Front

What is the purpose of a Punnett square?

Back

A Punnett square is used to predict the genotypes and phenotypes of offspring from a genetic cross.

Front

What is the significance of homozygous and heterozygous genotypes?

Back

Homozygous genotypes have two identical alleles (e.g., AA or aa), while heterozygous genotypes have two different alleles (e.g., Aa).

Front

What is the expected genotype of offspring from a cross between Aa and Aa?

Back

The expected genotypes are 25% AA, 50% Aa, and 25% aa.

Front

What is the definition of an allele?

Back

An allele is a variant form of a gene that can produce different traits.

Front

How do you determine the phenotype from a genotype?

Back

The phenotype is determined by the expression of the dominant alleles present in the genotype.