Introduction to Mendelian Genetics and Monohybrid Crosses

Gregor Mendel

19th-century monk, father of genetics.

Traits

Different characteristics observed in organisms.

Heredity

Study of how traits are passed to offspring.

True Breeding

Plants consistently show the same traits across generations.

P Generation

Parent generation in Mendel's experiments.

F1 Generation

First filial generation from parental cross.

F2 Generation

Second filial generation from F1 cross.

Dominant Alleles

Traits that always express in the organism.

Recessive Alleles

Traits that express only when homozygous.

Alleles

Different forms of a gene inherited from parents.

Hybrid

Organism with two different alleles.

Purebred

Organism with two identical alleles.

Homozygous

Two identical alleles for a trait.

Heterozygous

Two different alleles for a trait.

Genotype

Genetic makeup represented by letters.

Phenotype

Physical appearance resulting from genotype.

Monohybrid Cross

Cross examining one trait between two parents.

Punnett Square

Diagram predicting offspring genotypes from crosses.

Dominant Representation

Capital letters denote dominant alleles.

Recessive Representation

Lowercase letters denote recessive alleles.

Segregation

Separation of alleles during gamete formation.

Dominant Trait Example

Tallness in pea plants masks shortness.