Not yet registered?

You are now "Test Driving" Teachers' Domain

You may view up to 7 resources in this limited trial period.

You have 6 views remaining. Register now for unlimited free access and to download, share, and save resources. Learn More

About Registration:

Registering with Teachers' Domain is free and allows you to:

• View as many resources as you like
• Save, sort, and share resources using My Folders and My Groups
• Download resources to your desktop
• See standards correlations for your state

Thank you for "Test Driving" Teachers' Domain

You have viewed all seven resources permitted in this limited trial period. You may continue to browse the site, but to view, download, share, and save resources, you must register now. Registration is simple, safe, and free.

For more information:

Learn about our online Professional Development Courses, or review our Privacy Policy.

If you still have questions, please contact us.

Recommended for: Grades 9-12

Resource: Molecular Clocks: Proteins That Evolve at Different Rates

Save to a folder

Media Type:
PDF Document

Size: 40.4 KB

Four different proteins from humans and horses are compared in this graphic and article, and the reasons each protein evolves at its own characteristic rate are discussed. Each protein is useful for measuring evolutionary change over a different time scale.

Background Essay
Discussion Questions
Standards

The basic mutation rate is probably similar for all genes, but natural selection filters out mutations that adversely affect the functioning of the protein each gene makes. The structure of some proteins is rigidly defined by the function they perform -- any mutation that causes even a small change in the molecular structure will impair the protein's function. These proteins accumulate very few mutations and may be identical in many species, which means they have limited use in working out how closely different species are related. Other proteins can tolerate a large amount of change and still carry out their function. Such proteins accumulate many mutations, and they can be used to help work out the evolutionary relationships between even closely related species.

Teachers' Domain is proud to be a Pathways portal to the National Science Digital Library.

Resource: Molecular Clocks: Proteins That Evolve at Different Rates

Loading Standards

Topics Covered:

Lesson Plans Using This Resource:

Source: Adrienne Zihlman, The Human Evolution Coloring Book

Produced for Teachers' Domain by:

Collection Developed for Teachers' Domain by:

Collection Funded by: