Genetics Exam Questions

Methods used to determine if an individual has two identical or two different alleles for a particular gene.

Pea plants were used by Mendel because they had easily observable contrasting traits and were readily available.

During gamete formation, alleles for each gene separate from each other, ensuring that each gamete receives only one allele.

Both alleles of a gene are expressed in the heterozygote; neither allele is completely dominant or recessive.

Genes for different traits are inherited independently of each other, meaning the allele inherited for one trait doesn't influence which allele is inherited for another trait.

A tool used to predict the possible genotypes and phenotypes resulting from a genetic cross.

Alternative forms of a gene that occupy the same locus on homologous chromosomes.

A pattern where an affected person usually inherits the affected allele from one of the parents, meaning if one parent carries the mutant allele, a child has a 50% chance of inheriting it.

When the activity of one gene is suppressed by the activity of a different, non-allelic gene.

An autosomal recessive disorder affecting the lungs and other organs.

A genetic ratio indicative of epistasis (interaction between genes affecting a trait).

The equilibrium where the rate of appearance of a deleterious mutation is balanced by the rate of removal by natural selection.

Probability of getting an AABB genotype in self-fertilized AaBb plant (assuming independent assortment) is 1/16.

If half (50%) offspring are recessive (aa), the parents most likely have a heterozygous/carrier genotype (Aa).

Condition expressed in both males and females if a gene copy of the allele is present.

A genetic condition where two copies of an abnormal gene must be present for the trait to be expressed; affected individuals usually have unaffected parents.

A genetic condition where an affected gene on the X chromosome is enough to cause the trait; more females than males are typically affected.

A person who carries an abnormal gene but does not show symptoms of the trait.

The failure of homologous chromosomes or sister chromatids to separate properly during meiosis.

A genetic condition where there are three copies of chromosome 21; a common cause of Down syndrome.

An individual with two different mutant alleles of a gene.

The likelihood of an individual carrying a recessive trait based on family history

Failure of homologous chromosomes or sister chromatids to separate properly during meiosis, leading to abnormal chromosome numbers in gametes.

A genetic condition resulting from an extra X chromosome (47,XXY), primarily affecting males, characterized by various physical and developmental features.

A genetic condition resulting from a missing or incomplete X chromosome (45,X), primarily affecting females.

The process of arranging chromosomes in pairs to visualize and analyze their structure and number.

Exchange of segments between two non-homologous chromosomes.

Visualizing specific patterns or bands on chromosomes to study their structure.

A reciprocal translocation between chromosome 9 and 22 that is linked to Chronic Myelogenous Leukemia (CML).

A specialized region on some chromosomes where the DNA is less tightly packed, often containing genes involved in cell division or chromosome function.

A translocation where a piece of chromosome 9 (long arm, q34) swaps with a piece of chromosome 22 (long arm, q11). It's linked to chronic myeloid leukemia.

A structural chromosome alteration where an extra piece of chromosome 19 (short arm, p13) is added to one of the chromosomes. This leads to a duplication.

The three types of color blindness: red (X-linked), green (X-linked), and blue (autosomal). These are caused by mutations in specific genes on their respective chromosomes.

In females, one X chromosome is randomly inactivated, becoming a Barr body. This inactivated X chromosome absorbs stain more readily due to its condensed state.

Chromosomes form bands when stained, revealing their structure. This is due to variations in DNA density, histone composition, and gene expression.

The SRY gene, located on the Y chromosome, is responsible for male sex determination. It triggers the development of testes and male sexual characteristics.