Inheritance II: Mendelian Traits

These flashcards cover key concepts from the lecture on Mendelian traits, focusing on inheritance patterns, Mendel's hypotheses, laws, and the principles applied to human genetics.

What key terms should students be able to use accurately by the end of the lecture?

Students should be able to use terms such as genotype, phenotype, allele, homozygous, heterozygous.

What is the hypothesis Mendel tested in his pea experiments?

Mendel hypothesized that when two strains of peas with contrasting traits are bred, their characteristics are irreversibly blended in succeeding generations.

What are Mendel's two laws of inheritance?

1. Law of Segregation: gene copies separate so each gamete receives one copy. 2. Law of Independent Assortment: alleles assort independently during gamete formation.

What is an example of a phenotype ratio expected in Mendel's experiments with purple and white flowers?

In the F2 generation, the expected phenotype ratio is 3:1 for purple to white flowers.

What is the probability of inheriting a recessive allele from both parents?

The probability is P(r sperm) AND P(r egg) = 0.5 x 0.5 = 0.25.

What are the three types of dominance in genetics?

1. Simple/Complete Dominance, 2. Incomplete Dominance, 3. Codominance.

In a cross of a homozygous black pacer and a homozygous chestnut trotter, what phenotype do you expect in F1 generation?

The expected phenotype of F1 generation will be black trotters.

What probability results from calculating P(Yr) from a parental cross?

P(Yr) = P(Y) x P(r) = 0.5 x 0.5 = 0.25.

How do Mendel's principles apply to human genetics?

Humans are diploid, meaning we have two copies of each chromosome, allowing for Mendelian inheritance patterns.

What does it indicate if a pedigree shows affected offspring from heterozygous parents?

It may indicate that homozygous recessive offspring (affected) can occur.