Genetics Trivia

Every living thing carries an instruction manual written in a four-letter code, tucked inside nearly every cell it has. Genetics is the study of that code: how it's copied, how it gets passed from parent to offspring, and why siblings can share a house and a last name while looking nothing alike. This quiz covers the core vocabulary and history of the field.

Mendel's Garden Full of Peas

Long before anyone had seen a chromosome, an Austrian monk named Gregor Mendel spent years cross-breeding pea plants and counting the results. His careful record-keeping revealed that traits are passed down in predictable ratios, laying the groundwork for the entire field of genetics decades before DNA was identified as the molecule responsible.

DNA's Double Helix

DNA's structure was described in 1953, and its now-famous twisted-ladder shape explains how it copies itself so reliably: each strand serves as a template for building its partner, base by base.

• Adenine always pairs with thymine.
• Guanine always pairs with cytosine.
• Humans carry 23 pairs of chromosomes in most cells.

Alleles, Traits, and Why Family Resemblances Vary

Genes come in different versions called alleles, and which combination you inherit determines everything from eye color to how you metabolize certain medications. Two identical alleles make an organism homozygous for that gene, while two different versions make it heterozygous.