Genetics Review for Biology EOC

Front

What is the definition of phenotype?

Back

Phenotype refers to the observable physical characteristics or traits of an organism, which are influenced by both genetic and environmental factors.

Front

What is the definition of genotype?

Back

Genotype refers to the genetic makeup of an organism, specifically the alleles it possesses for a particular trait.

Front

How many generations are typically represented in a pedigree chart?

Back

A pedigree chart can represent multiple generations, often showing 3 to 4 generations of ancestry.

Front

What does a Punnett square illustrate?

Back

A Punnett square is a diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles from the parents.

Front

In a genetic cross, what does 'homozygous recessive' mean?

Back

Homozygous recessive refers to an organism that has two identical recessive alleles for a particular trait (e.g., 'tt' for short plants).

Front

What is the probability of producing a homozygous dominant offspring from a Tt x Tt cross?

Back

The probability of producing a homozygous dominant offspring (TT) from a Tt x Tt cross is 25%.

Front

What is the probability of producing a short plant (tt) from a Tt x Tt cross?

Back

The probability of producing a short plant (tt) from a Tt x Tt cross is 25%.

Front

What does it mean if a trait is dominant?

Back

A dominant trait is one that is expressed in the phenotype even when only one allele is present (e.g., T for tall plants).

Front

What does it mean if a trait is recessive?

Back

A recessive trait is one that is expressed in the phenotype only when two recessive alleles are present (e.g., tt for short plants).

Front

How can you determine the number of affected individuals in a pedigree?

Back

You can determine the number of affected individuals in a pedigree by counting the individuals that express the trait of interest.