Mendel, Genes, and Inheritance

This set of flashcards covers important concepts related to Mendel's theories on genetics, inheritance patterns, and the experiments he conducted using pea plants.

What are genes often referred to as?

Blueprints for inheritance.

What shape do red blood cells take in sickle-cell disease?

Donut shaped.

What does a mutation in a gene affect?

Nucleotide sequence, which can lose the function of transporting oxygen.

What theory of inheritance was prevalent before Mendel's work?

Blending Theory of Inheritance.

What did Gregor Mendel use to become the father of genetics?

Scientific method to study inheritance.

How many hypotheses did Mendel propose?

Two hypotheses.

What is a true-breeding garden pea?

Plants that self-fertilize and maintain the same trait in each generation.

What is the P generation?

Parents used in the initial cross in breeding experiments.

What results from the cross of purple and white flowered peas in Mendel's experiments?

All offspring are purple flowers in the F1 generation.

What is the phenotypic ratio in the F2 generation of flower color crosses?

3:1 ratio of purple to white flowers.

What allele combination represents heterozygous?

Pp.

What does the term phenotype represent?

Outward appearance or characteristics of an organism.

What is the significance of Mendel's Principle of Segregation?

Alleles of each gene separate during gamete formation.

What is the result of a dihybrid cross involving round and yellow peas?

Produces phenotypic ratio of 9:3:3:1.

What does a testcross help to determine?

The genotype of an individual with a dominant phenotype.

What is epistasis?

When one gene masks or alters the expression of another gene.

What is polygenic inheritance?

A trait controlled by multiple genes, producing continuous variation.

What inheritance pattern do blood types in humans follow?

Multiple alleles and co-dominance.

What does pleiotropy refer to?

One gene affecting multiple phenotypic traits.

What do we observe in Mendel's pea plant experiments regarding inheritance?

Traits are inherited as discrete factors.

What determines the phenotype of a gene with multiple alleles?

The relationship between the different pairs of alleles.

What happens to homozygous recessive individuals with sickle cell disease?

They display severe symptoms.

Incomplete dominance results in what type of phenotype?

A blended phenotype different from either parent.

What is the expected phenotypic ratio in an incomplete dominance situation involving snapdragons?

1:2:1 ratio of red, pink, and white flowers.

What characterizes Mendel's third hypothesis?

Alleles segregate independently during gamete formation.

What traits did Mendel study in peas?

Seed shape, flower color, and pod shape.

What major contribution did Walter Sutton provide to genetics?

He linked genes to chromosomes and how they segregate during meiosis.

What is Mendel's Law of Independent Assortment?

Alleles for different traits are distributed to gametes independently.

How does one determine if a purple-flowered plant is homozygous or heterozygous?

By performing a testcross with a homozygous recessive plant.

What is the ratio of expected phenotypes resulting from a dihybrid cross?

9:3:3:1 ratio.