Chapter 26

Name and describe the three domains of life.

Describe shared and contrasting features of bacterial and archaeal cells.

Explain how prokaryotic cells obtain nutrients and how this process puts constraints on their size.

Explain how photosynthesis can occur without the production of oxygen, and how respiration can occur without requiring oxygen.

Describe the roles of bacteria and archaeons in the sulfur and nitrogen cycles.

Explain how horizontal gene transfer complicates our understanding of evolutionary relationships among bacteria and archaeons.

Name and describe three major groups of Bacteria.

Name and describe three major groups of Archaea.

State the age of Earth and the time when life is thought to have first originated.