Base Genetics

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., BB, Bb, bb).

Front

What is the difference between homozygous and heterozygous genotypes?

Back

Homozygous genotypes have two identical alleles (e.g., BB or bb), while heterozygous genotypes have two different alleles (e.g., Bb).

Front

What does homozygous recessive mean?

Back

Homozygous recessive refers to having two identical recessive alleles for a trait (e.g., tt).

Front

What does heterozygous mean?

Back

Heterozygous means having two different alleles for a trait (e.g., Bb).

Front

What is an allele?

Back

An allele is a variant form of a gene that can produce different traits (e.g., B and b are alleles for a gene controlling color).

Front

What is the phenotype?

Back

The phenotype is the observable physical or biochemical characteristics of an organism, determined by its genotype (e.g., brown fur).

Front

What does it mean if an organism is homozygous dominant?

Back

An organism is homozygous dominant if it has two identical dominant alleles for a trait (e.g., BB).

Front

What is a dominant allele?

Back

A dominant allele is an allele that expresses its trait even in the presence of a recessive allele (e.g., B in Bb).

Front

What is a recessive allele?

Back

A recessive allele is an allele that only expresses its trait when two copies are present (e.g., b in bb).

Front

What is a Punnett square?

Back

A Punnett square is a diagram used to predict the genetic outcomes of a cross between two organisms.