Study Guides

Unit Summary

This unit covers the structure and function of eukaryotic and prokaryotic cells, DNA as the genetic material, and key genetic terms. It also explains protein synthesis, genetic variants, and how DNA structure affects proteins. The emphasis is on using models to explain scientific concepts.

Lesson Summary

You will learn to explain how a genetic variant in a non-coding part of the genome can influence an organism's phenotype.

Key Notes

• When a cell copies a gene to make mRNA (the instructions to make a protein), this is called gene expression.
• Only around 1-2% of the genome is genes; the rest contains code that controls gene expression.
• A genetic variant in a non-gene (so called "non-coding") section of the genome can affect gene expression.
• Non-coding DNA affects gene expression because it is where RNA polymerase starts copying the gene for protein synthesis.
• Genetic variants in non-coding DNA can impact gene expression and therefore an organism's phenotype.

Vocabulary To Learn

• gene: A section of DNA that holds the genetic code for a protein.
• protein: A chemical substance whose structure is coded for by the genetic code in genes.
• gene expression: The process in which genes are copied during the first step in protein synthesis.
• genetic variant: Produced when a mutation causes a change in the genetic sequence of a gene or non-coding section of DNA.
• phenotype: The physical characteristics of an organism.

Common Mistakes To Avoid

• All DNA is genes that code for proteins; and that our characteristics are only affected by our genes

3 Quick Questions (With Answers)

More Lessons In This Unit

• Genetic variants in genes can influence phenotype Study Guide
• Mutations and genetic variants Study Guide
• Protein synthesis Study Guide
• The chemical structure of DNA Study Guide
• The genetic code Study Guide
• The genome Study Guide
• The genome, the environment and phenotype Study Guide
• The structure of DNA Study Guide