Pedigrees and Punnett Squares

Front

What is a pedigree?

Back

A pedigree is a diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism and its ancestors.

Front

What does a Punnett square illustrate?

Back

A Punnett square illustrates the possible genetic combinations of offspring from two parents.

Front

Define phenotype.

Back

Phenotype is the observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences.

Front

What is the difference between genotype and phenotype?

Back

Genotype refers to the genetic constitution of an individual, while phenotype refers to the observable traits.

Front

What does homozygous mean?

Back

Homozygous means having two identical alleles for a particular gene.

Front

What does heterozygous mean?

Back

Heterozygous means having two different alleles for a particular gene.

Front

What is codominance?

Back

Codominance is a genetic scenario where both alleles in a heterozygote are fully expressed, resulting in a phenotype that is neither dominant nor recessive.

Front

What is incomplete dominance?

Back

Incomplete dominance is a genetic situation where one allele does not completely dominate another, resulting in a new phenotype that is a blend of the two.

Front

How is colorblindness inherited?

Back

Colorblindness is often inherited in an X-linked recessive pattern, meaning it is passed down through the X chromosome.

Front

What is the significance of the X chromosome in inheritance?

Back

The X chromosome carries many genes, including those related to color vision; males have one X chromosome, while females have two.