Patterns of inheritance

Genotype

The genetic constitution of an organism.

Phenotype

The expression of the genes and its interaction with the environment.

Homozygous

A pair of homologous chromosomes carrying the same alleles for a single gene.

Heterozygous

A pair of homologous chromosomes carrying two different alleles for a single gene.

Codominant

Both alleles are equally dominant and expressed in the phenotype.

Multiple alleles

More than two alleles for a specific gene.

Sex-linkage

A gene whose locus is on the X chromosome.

Autosomal linkage

Genes that are located on the same chromosome (not the sex chromosome).

Epistasis

When one gene modifies or masks the expression of a different gene on a different locus.

Environmental factors

Influence phenotype, e.g., water availability, temperature, nutrients.

Genetic diversity

Differences in DNA between individuals and populations, aiding adaptation.

Continuous variation

Many genes involved, e.g., height, influenced by environment and genetics.

Discontinuous variation

One or two genes involved, distinct categories with no intermediates.

Natural selection

Process favoring advantageous alleles, leading to evolution.

Artificial selection

Humans breed organisms with desired traits, reducing genetic diversity.

Speciation

Formation of new species due to reproductive isolation and genetic differences.

Genetic drift

Change in allele frequency within a population, more pronounced in smaller populations.

Genetic bottlenecks

Events reducing population size, leading to loss of genetic diversity.

Founder Effect

Small group establishes a new population, limited genetic diversity.

Ethical considerations

Concerns about artificial selection, impact on health, diversity, and welfare.