Exam 4: Extensions of Mendelian Inheritance

In a dihybrid cross of two heterozygous individuals, you expect a 9:3:3:1 phenotypic ratio in the offspring, but observe a ratio of 9:7. What is the most likely explantation?

Paralogs are often functionally redundant and can compensate for the loss of either of the paralogs in a set.

Human blood groups are determined by antigens on the surface of red blood cells.

How did Bateson and Punnett's work with comb morphology in chickens differ from the dihybrid work of Mendel?

If a light-eosin eye male Drosophila is crossed to a homozygous red eyed female, what will be the phenotype of their offspring?

Variable expressivity means that the phenotype of a trait can vary between individuals.

In four-o'clock plants, red flower color is dominant to white flower color. However, heterozygous plants have a pink color. If a pink-flowered plant is crossed with a white-flowered plant, what will be the phenotypic ratios of their offspring?

A heterozygote possesses a phenotype that is intermediate between the homozygous dominant and homozygous recessive phenotypes. This is most likely an example of ________.

The interaction of two genes to produce a phenotype was first described by __________.

If a combination of two or more genes is required to produce a specific trait, it is called a(n) _______.

The pedigree below shows the inheritance pattern of a rare allele for one family. The filled in circles and square show affected individuals. What is the probability of individual III-2 being born female and affected?

Genes that are not required for survival, but are likely to be beneficial to the organism, are called _________.

Heavy metals, such as copper, are required for proper development. However, if too much copper is present it can lead to developmental defects. A scientist was interested in studying the developmental defects that could occur at various concentrations of copper. Genetically identical organisms were grown in 6 different concentrations of copper. This experiment evaluates a(n) _____________.

Filled in circles and square show affected individuals. Select the mode of inheritance for individual III-3

Typically, a recessive allele increases the expression of a functional protein.

The pedigree below shows the inheritance pattern of a rare allele for one family. The filled in circles and square show affected individuals. What is the probability of individual III-2 being born male and affected?

In rabbits, full coat color (c) is the dominant trait. A second allele, chinchilla (c^ch) is recessive to full coat color. Himalayan coat color (c^h) is recessive to chinchilla and full coat colors and albino (c) is recessive to all coat colors. If two chinchilla rabbits mate, what coat color is not possible in their offspring?

In human blood groups, the fact that an individual can have an AB blood type is an example of ___________.

If a geneticist describes a trait as being 70% penetrant, what would they mean?

Huntington disease in humans is an example of a(n) ____________.