10 Questions
What is the fundamental principle of the law of independent assortment?
The law of independent assortment states that when one allele pair separates, it is equally likely for each of the alleles in that pair to end up with either of the alleles in another pair.
What is the genetic phenomenon where the action of one gene blocks or silences the action of another gene?
Epistasis
In the example of the mottled agouti coat color in mice, what is the effect of the recessive c allele on pigment production?
The recessive c allele does not produce pigment, resulting in an albino phenotype.
Why did Mendel's studies with peas only show a single gene affecting a single character?
Mendel's studies were limited to a specific set of genes and traits, which did not exhibit complex interactions.
What is the difference between additive and sequential effects of genes on a character?
Additive effects occur when multiple genes contribute to a trait in a cumulative manner, while sequential effects occur when genes work in a specific order to produce a trait.
How do genes act antagonistically in certain cases?
Genes can act antagonistically by working against each other, cancelling or reducing the effect of one or both genes.
What is the significance of the A/a gene in the example of the mottled agouti coat color in mice?
The A/a gene controls coat color.
What is the relationship between the C gene and the A gene in the example of the mottled agouti coat color in mice?
The C gene is epistatic to the A gene, meaning that the C gene's action affects the expression of the A gene.
Why is it important to consider epistasis when studying genetic inheritance?
Epistasis can significantly affect the expression of traits and the interpretation of genetic data.
What is the main difference between the genetic inheritance of simple traits and complex traits?
Simple traits are controlled by a single gene, while complex traits are affected by multiple genes and their interactions.
Study Notes
Mendel's Law of Independent Assortment
- Mendel's law states that all allele pairs assort independently from each other, but this is not entirely true.
- Genes located close to each other on a chromosome are more likely to be inherited together.
- When two genes are on different chromosomes, the allele pairs can assort independently because the chromosomes do.
- When the genes are on the same chromosome, the alleles that are on the same piece of DNA are "stuck" together and are unlikely to mix with other alleles.
Linked Genes
- Genes that are near each other on the same chromosome are linked.
- Linked genes are unlikely to mix with other alleles unless a crossover occurs in between the two genes.
- Crossover must happen in between the two genes to generate new combinations (recombinants).
Mendel's Dihybrid Cross
- Mendel's second law describes the inheritance pattern of two different genes.
- The law of independent assortment states that when one allele pair separates, it is equally likely for each of the alleles in that pair to end up with either of the alleles in another pair.
Epistasis
- Epistasis is a phenomenon where the action of one gene blocks or silences the action of another gene.
- In the example of the mottled agouti coat color in mice, the C gene is epistatic to the A gene.
- The recessive c allele does not produce pigment, and a mouse with the homozygous recessive cc genotype is albino regardless of the allele present at the A locus.
Complexity of Characters
- Most characters are affected by more than one gene.
- Genes can have additive effects on a character, work in pathways and act sequentially, or even act antagonistically.
- Epistasis is one example of how genes can interact with each other.
Learn about Mendel's law of independent assortment, which states that all allele pairs assort independently from each other. Understand the principles of heredity and genetics.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
