AJH Pedigrees Test 2024

Front

What is a pedigree chart?

Back

A pedigree chart is a diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism and its ancestors, used to analyze the inheritance of traits.

Front

What does it mean if a trait is dominant?

Back

A dominant trait is one that will appear in the phenotype even if only one allele is present. It masks the effect of a recessive allele.

Front

What does it mean if a trait is recessive?

Back

A recessive trait is one that will only appear in the phenotype if two copies of the recessive allele are present.

Front

How can you determine the genotype of an individual with a dominant trait?

Back

You can determine the genotype by performing a test cross with a homozygous recessive individual. If any offspring display the recessive trait, the individual is heterozygous.

Front

What is the significance of carriers in genetic diseases?

Back

Carriers are individuals who have one copy of a recessive allele for a genetic disease but do not exhibit symptoms. They can pass the allele to their offspring.

Front

How many generations are typically represented in a pedigree chart?

Back

A pedigree chart can represent multiple generations, often at least three, to show the inheritance pattern of traits.

Front

What is the purpose of using Roman numerals in pedigree charts?

Back

Roman numerals are used to denote generations in a pedigree chart, with I representing the first generation, II the second, and so on.

Front

What does it mean if an individual is labeled as 'affected' in a pedigree?

Back

An 'affected' individual in a pedigree chart is one who expresses the trait or condition being studied, often marked with a filled symbol.

Front

What is the role of a Punnett square in genetics?

Back

A Punnett square is a tool used to predict the genotypes of offspring from a genetic cross, showing the probability of inheriting particular alleles.

Front

What is the difference between phenotype and genotype?

Back

Phenotype refers to the observable characteristics of an individual, while genotype refers to the genetic makeup or alleles present.