The document discusses basic concepts in Mendelian genetics including genes, alleles, genotypes, phenotypes, dominant and recessive traits, and homozygous and heterozygous individuals. It defines key terms and provides examples. Some main points: - Gregor Mendel is considered the father of genetics for his experiments breeding pea plants. - Genes are portions of DNA that code for traits, alleles are different forms of the same gene. - Genotype refers to an individual's genetic makeup, phenotype to their observable traits. - Dominant traits require only one allele, recessive traits require two of the same allele.