Pedigree Practice

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 sex-linked?

Back

A sex-linked trait is one that is associated with a gene that is carried only by the male or female parent, often located on the X or Y chromosome.

Front

What is the difference between autosomal dominant and autosomal recessive inheritance?

Back

In autosomal dominant inheritance, only one copy of the dominant allele is needed for the trait to be expressed. In autosomal recessive inheritance, two copies of the recessive allele are needed for the trait to be expressed.

Front

How can you identify a carrier in a pedigree?

Back

A carrier is an individual who has one copy of a recessive allele but does not express the trait. In a pedigree, carriers are often represented by individuals who have affected offspring but are not affected themselves.

Front

What does the term 'genotype' refer to?

Back

Genotype refers to the genetic constitution of an individual, specifically the alleles present at a particular gene locus.

Front

What is the significance of the 'hh' genotype in autosomal recessive disorders?

Back

The 'hh' genotype indicates that an individual is homozygous recessive and will express the autosomal recessive trait.

Front

What does it mean if a trait is autosomal dominant?

Back

If a trait is autosomal dominant, it means that only one copy of the dominant allele is required for the individual to express the trait.

Front

How can you determine the mode of inheritance from a pedigree?

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The mode of inheritance can be determined by analyzing the pattern of affected individuals, the presence of carriers, and whether the trait appears in every generation.

Front

What is the role of sex chromosomes in inheritance?

Back

Sex chromosomes (X and Y) determine an individual's sex and can carry genes that influence traits, leading to sex-linked inheritance patterns.

Front

What is a phenotype?

Back

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