Genetics: Punnett Squares

Front

What is a homozygous recessive allele pair?

Back

A homozygous recessive allele pair consists of two identical recessive alleles, such as 'rr'.

Front

What is a homozygous allele pair?

Back

A homozygous allele pair consists of two identical alleles, which can be either dominant (e.g., 'BB') or recessive (e.g., 'rr').

Front

What is a Punnett square used for?

Back

A Punnett square is a diagram used to predict the genetic outcomes of a cross between two organisms, showing the possible allele combinations in the offspring.

Front

What is the probability of an offspring showing a recessive trait if the Punnett square shows a 25% chance?

Back

The probability of the offspring showing the recessive trait is 25%.

Front

What does it mean if the probability of homozygous dominant offspring is 0%?

Back

If the probability of homozygous dominant offspring is 0%, it means that it is impossible for the offspring to inherit two dominant alleles from the parents.

Front

What is the definition of alleles?

Back

Alleles are different forms of a gene that can exist at a specific locus on a chromosome.

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 only express their trait when two copies are present.

Front

How do you determine the genotype of an organism?

Back

The genotype of an organism is determined by the specific alleles it carries, which can be homozygous or heterozygous.

Front

What does it mean for an organism to be heterozygous?

Back

An organism is heterozygous when it has two different alleles for a particular gene, such as 'Ww'.

Front

What is the significance of the 1:2:1 ratio in a monohybrid cross?

Back

The 1:2:1 ratio in a monohybrid cross represents the expected genotypic ratio of the offspring when crossing two heterozygous parents.