Module 5: Mendelian Genetics and Genetic Disorders

Girl looking in the mirror

Have you ever looked in the mirror and wondered which traits you inherited from your mother and which came from your father? You might have dark hair and your brother(s) and/or sister(s) have blonde hair. How could this have occurred? In this module, you will learn about the study of how traits are passed from parent to offspring, or genetics. Along with your exploration of genetics, physical traits, and heredity, you will learn how some diseases and medical conditions are passed down from one generation to the next.

Getting Started

mom and sonLog IconPhysical characteristics, or traits, define many of the features of your body. These physical traits were determined by genetics. The first thing you may notice when you look at someone could be their hair color, eye color, or height. When fertilization occurs, each parent may contribute dominant or recessive genes that will determine the offspring's physical traits. Before you begin learning about genetics, see how many dominant and recessive traits you have. Access the Dominant and Recessive Characteristics Table and check off all your dominant and recessive traits.

Key Vocabulary

Vocabulary Icon
To view the definitions for these key vocabulary terms, visit the course glossary.

allele genetics nondisjunction
autosomes heredity pedigree
carrier heterozygous phenotype
chromosomes homozygous polygenic traits
codominant incomplete dominance Punnett square
dihybrid cross karyotype recessive
dominant monohybrid cross sex-linked traits
gene monosomy trisomy