This interactive will present the mathematical consideration of exponentially
enriching a piece of DNA using PCR. Typically, a PCR protocol will repeat
approximately 30 cycles of denaturation, annealing, and elongation. 30 cycles of
PCR produce around 1 billion copies of the amplified region.

A video discussing a variety of biotechnology applications that can be completed based on DNA's chemical properties. [2:44]

Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.

By the end of this section, you will be able to do the following:

Describe nucleic acids' structure and define the two types of nucleic acids
Explain DNA's structure and role
Explain RNA's structure and roles

Discusses the structure and role of nucleic acids.

A free CK-12 account is required to view all materials.

This pathway provides an overview of the four classes of biological molecules (lipids, carbohydrages, proteins and nucleotides) and how they are assembled.

This scrollable interactive takes users on a tour of the DNA double helix, explaining how nucleotide base pairing leads to DNA's unique shape.

Explore the relationship between the genetic code on the DNA strand and the resulting protein and rudimentary shape it forms. Through models of transcription and translation, you will discover this relationship and the resilience to mutations built into our genetic code. Start by exploring DNA's double helix with an interactive 3D model. Highlight base pairs, look at one or both strands, and turn hydrogen bonds on or off. Next, watch an animation of transcription, which creates RNA from DNA, and translation, which 'reads' the RNA codons to create a protein.

This narrated animation schematically shows the process of protein synthesis. [3 min, 24 sec]

Learn the molecular structure of DNA including the nucleotide, nitrogenous base, and phosphate. [13:00]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Travel deep into the human body to see exactly where your DNA resides. From the NOVA: Cracking the Code of Life Web site.

This pathway provides an introduction to nucleic acids and their role in providing heritable information in cells. For a deeper look at this topic, we recommend the pathway DNA Structure and Function from the OpenStax textbook Biology for AP® Courses.

PCR, or polymerase chain reaction, is a powerful lab technique used to generate billions of copies of a specific stretch of DNA. This video animation illustrates the process of PCR.

This interactive will present the components and steps needed for a successful
PCR reaction.

This interactive will present the rules for designing precise nucleotide sequences
called PCR primers. Designing primers for a PCR reaction is an important step
because the way they bind to the template DNA dictates much of the success of
the PCR reaction.

Polymerase Chain Reaction - or PCR - is known as one of the most ubiquitous and powerful techniques in life science laboratories. PCR is a highly sensitive and selective method to produce many copies of a particular piece of DNA. This pathway details applications of PCR, its mechanism and primer design, and demonstrates how the method is used in the lab.