Genotype & Phenotype

Front

What is a genotype?

Back

The genetic makeup of an organism, represented by the alleles it possesses (e.g., AA, Aa, aa).

Front

What is a phenotype?

Back

The observable physical or biochemical characteristics of an organism, determined by its genotype and environment (e.g., flower color, eye color).

Front

What does homozygous mean?

Back

Having two identical alleles for a particular gene (e.g., AA or aa).

Front

What does heterozygous mean?

Back

Having two different alleles for a particular gene (e.g., Aa).

Front

What is the difference between dominant and recessive alleles?

Back

Dominant alleles express their trait even when only one copy is present, while recessive alleles require two copies to express their trait.

Front

If a plant has the genotype Pp, what is its phenotype if P (purple) is dominant over p (white)?

Back

Purple flowers.

Front

What is the phenotype of an organism with the genotype rr if r is recessive?

Back

White flowers (if r represents a trait for flower color).

Front

What does it mean if an organism is homozygous recessive?

Back

It has two recessive alleles for a trait (e.g., aa).

Front

What is an example of a phenotype?

Back

Blue eyes, tall height, or purple flowers.

Front

If brown eyes (B) are dominant over blue eyes (b), what is the phenotype of a Bb genotype?

Back

Brown eyes.