Genetics Chapter 5 Quiz

Genetic disorders caused by mutations in a single gene.

The inheritance pattern of single-gene disorders, following rules described by Gregor Mendel.

The likelihood that a gene mutation will result in disease expression.

Variation in severity of disease symptoms among individuals with the same gene mutation.

A family tree that tracks traits or conditions through generations using symbols and lines.

A pattern of inheritance where two copies of a mutated gene are needed for the disorder to manifest. Individuals with one mutated copy are carriers.

A pattern of inheritance where only one copy of a mutated gene is needed for the disorder to manifest. Affected parents have a 50% chance of passing it on.

A pattern of inheritance where a mutated gene resides on the X chromosome. Males are more likely to be affected due to having only one X chromosome.

A pattern of inheritance where a mutated gene resides on the X chromosome. Affected females usually have milder symptoms than affected males.

A pattern of inheritance where genes located on the X and Y chromosomes can be exchanged between genders.

A pattern of inheritance where gene expression differs depending on the parent of origin. One parent's copy is 'switched off'.

A condition where a child inherits two copies of a chromosome from the same parent instead of one from each parent.

A condition where a mutation occurs in some cells but not all cells of a person's body.

A genetic condition where a mutation occurs in the germ cells (sperm or egg) of a parent, but not in all of their cells. This means that the parent may not show any symptoms of the condition but can transmit it to their offspring.

Regions located at the ends of the X and Y chromosomes that are homologous (similar) and can exchange genetic material during meiosis. These regions ensure proper segregation of sex chromosomes during cell division.

Located at the distal ends of the short arms of the X and Y chromosomes, PAR1 is involved in pairing and recombination during meiosis, ensuring proper segregation of chromosomes.

Located at the tips of the long arms of the X and Y chromosomes, PAR2 is smaller than PAR1 and undergoes recombination during meiosis, but contains fewer genes compared to PAR1.

The exchange of genetic material between the X and Y chromosomes in the pseudoautosomal regions (PARs) during meiosis, ensuring proper segregation of chromosomes and contributing to genetic diversity.

An individual who carries two different mutated alleles for the same gene, one from each parent.

A single-gene disorder caused by mutations in the COL1A1 or COL1A2 gene, leading to bone fragility and other skeletal problems.

Sex-linked pedigrees show distinct inheritance patterns compared to autosomal pedigrees, including differences in transmission between genders and the likelihood of affected individuals based on sex.

Changes in the LDLR gene reduce the ability of cells to remove LDL cholesterol from the bloodstream, leading to higher LDL-C levels.

Mutations in the APOB gene affect the structure or function of apolipoprotein B, a key component of LDL particles, impairing LDL clearance and increasing cholesterol levels.

Changes in the PCSK9 gene lead to increased degradation of LDL receptors, decreasing LDL clearance efficiency and raising LDL-C levels.

The effect of M3 mutation on the protein is to change the amino acid Serine (Ser) to Proline (Pro).

Mutations in the genes for collagen α1 and α2 chains disrupt the balance of these chains, leading to abnormal collagen formation or reduced collagen production.

PCD is an enzyme involved in the synthesis of BH4, a cofactor crucial for phenylalanine metabolism. PCD mutations cause BH4 deficiency, impacting PAH activity and resulting in phenylalanine buildup.

DHPR is vital for recycling BH4. Mutations in DHPR can also lead to BH4 deficiency, affecting PAH function and phenylalanine levels.

PTPS is another enzyme involved in BH4 biosynthesis. Mutations in PTPS can result in BH4 deficiency, impacting PAH activity and leading to elevated phenylalanine levels.

Heritability measures the proportion of variation in a trait within a population that's due to genetic factors, compared to environmental influences. It tells us how much genetics contribute to differences in a trait between individuals.

High heritability indicates that genetics have a significant influence on the variation of a trait within a population. It means that genetic differences between individuals are a major factor in how the trait manifests.

Low heritability means that environmental factors have a more substantial influence on the variation of a trait within a population. It means the environment plays a greater role than genes in shaping how that trait is expressed.

Children of identical twins share a higher percentage of their genetic material than cousins born to non-identical twin parents. They are genetically more similar to half-siblings but not identical because they still inherit genes from different parents.

Children of identical twins are legally and socially considered cousins. While they have a more significant genetic relatedness than cousins born to non-identical twin parents, their legal and social status remains as cousins.

Children of identical twins inherit their genetic material from both parents, just like half siblings. However, since identical twins share the same DNA, their children receive a higher percentage of the same genetic material compared to cousins born to non-identical twin parents.

Heritability is estimated by comparing phenotypic variations between related individuals in a population and by examining the link between an individual's phenotype and genotype.

Heritability doesn't apply to genetic differences between populations, only within a population. It doesn't predict these differences based on phenotypic variations, regardless of environment.

Measures the likelihood of an event happening in one group compared to another. A relative risk greater than 1 means the event is more likely, less than 1 means less likely.

A research method used to study heritability by comparing adopted individuals to both their biological and adoptive families.

Heritability doesn't mean a trait is entirely determined by genes. It doesn't tell us the specific genes involved, and it doesn't predict an individual's trait.

Heritability estimates can be used to understand the relative influence of genes and environment on traits like height, intelligence, and susceptibility to diseases.

Heritability can inform breeding programs in agriculture and provide insights into how genes contribute to complex traits like susceptibility to diseases.