Sex Chromosomes 4-2

These flashcards cover key terms and definitions related to traits transmitted through sex chromosomes, including concepts such as autosomes, sex-linked traits, and inheritance patterns.

Autosomes

Chromosomes 1 to 22 that come in pairs and carry the same genes along their length.

Sex Chromosomes

Special unmatched chromosome pairs that determine an individual's sex, consisting of X and Y chromosomes in humans.

Homologous Chromosomes

Chromosomes that match in shape and size and carry the same genes.

X Chromosome

The larger sex chromosome in humans that contains about 1,000 different genes.

Y Chromosome

The smaller sex chromosome in humans that carries about 50 genes.

X-linked Recessive Trait

A trait where the gene responsible is located on the X chromosome, and the trait is expressed more frequently in males.

Carrier

An individual who does not have a disease but possesses the allele for that disease.

Hemophilia

An example of an X-linked recessive trait, a blood clotting disorder.

Pedigree

A family tree that shows the inheritance of traits.

Crisscross Inheritance

A pattern of inheritance where a trait is passed from a mother to son and then from that son to his daughter.

Phenotype

The observable physical or biochemical characteristics of an organism.

Meiosis

The process of cell division that produces gametes with half the chromosome number.

Dominant Trait

A trait that is expressed in the phenotype even if only one allele is present.

Recessive Trait

A trait that is only expressed in the phenotype if two copies of the allele are present.

Random Fertilization

The process by which the combination of gametes occurs randomly, resulting in varied offspring genotypes.

Probability of Inheritance

The likelihood that a trait will be passed on from parents to offspring.