2GT3 Chapter 4 Part 2 (T/F)

In Drosophila, the white-eye trait follows the typical Mendelian inheritance pattern observed in monohybrid reciprocal crosses.

In humans, males can be homozygous for X-linked genes.

The crisscross pattern of inheritance involves passing X-linked traits from heterozygous mothers to all sons.

Sex-limited inheritance occurs when the expression of a phenotype is restricted to one sex only.

The phenotype in females with the genotype 'Hh' for hen-feathered trait will always be hen-feathered.

In X-linkage, genes are present on both the X and Y chromosomes.

X-linkage inheritance patterns can modify Mendelian ratios due to gene presence on the Y chromosome.

The white eye mutation in Drosophila exhibits X-linkage, with red eyes being the wild-type.

Marfan syndrome is caused by a mutation in a gene encoding for muscle tissue fibrillin.

Porphyria variegata is an autosomal recessive disorder related to lipid metabolism.

In dihybrid crosses, the classic F2 ratio is always 9:3:3:1.

Epistasis combines one or more of the four phenotypic categories in exactly three different ways.

When gene interaction controls phenotypic variation, the final ratio in dihybrid crosses can be expressed in sixteenths.

Complementation analysis is used to determine if mutations causing similar phenotypes are always in the same gene.

Complementation Example: In Drosophila, two true-breeding strains with wingless phenotypes must have mutations in the same gene.

Incomplete penetrance means that all individuals with the disease-causing mutation will develop the clinical symptoms of the disease.

Expressivity can only be measured qualitatively, not quantitatively.

Environmental factors such as diet, temperature, and light cycles do not have any impact on gene expression.

Reduction in phenotypic variation in a controlled environment suggests that genes have a greater influence on phenotype than the environment.

Complete penetrance means that all individuals with the disease-causing mutation will develop the clinical symptoms of the disease.

Two modes of inheritance can alter the 3:1 monohybrid ratio to a 9:3:3:1 dihybrid ratio.

Epigenesis states that each gene must carry out its activities in a random fashion.

Complementation is an example of pleiotropy.

X-linkage in humans can result in sex-limited inheritance.

Genetic maternal effect is an example of gene interaction.