Building a Reef

Introduction

Coral reefs are made of aragonite, a type of calcium carbonate (limestone) crystal that is secreted by coral polyps. The corals and zooxanthellae work together to extract materials out of seawater to form the hard exoskeletons that form reef structures. During this lab, you will learn about the life cycle of corals, including how they grow and reproduce. You will also consider the chemistry of seawater and demonstrate how calcium carbonate precipitates to form skeletal reef material.

After completing this investigation, you should be able to:

• explain the process by which corals extract reef-building material from seawater;
• describe how corals grow, reproduce, and form reef structures; and
• build physical models of coral growth, reproduction, and reef formation.

Keeping Track of What You Learn

Throughout these labs, you will find two kinds of questions.

• Checking In questions are intended to keep you engaged and focused on key concepts and to allow you to periodically check if the material is making sense. These questions are often accompanied by hints or answers to let you know if you are on the right track.
• Stop and Think questions are intended to help your teacher assess your understanding of the key concepts and skills you should be learning from the lab activities and readings.

Your teacher will let you know which answers you should record and turn in.