Chapter 30
Digestive & Excretory Systems


Q: How are the materials that enter and leave your body related to the processes that maintain homeostasis?

Think about it - The batter slaps a ground ball to the shortstop, who fields it cleanly and throws the ball toward your position - first base. In a single motion, you extend your glove hand, catch the ball, and extend your foot to touch the edge of the base. An easy out, a routine play. But think about how many systems of your body are involved in making this type of "routine" play. How do they all work together?

Key Questions Include:

How is the human body organized?
What is homeostasis?
What are the structures and functions of the major body systems?
Why do we need to eat?
What nutrients does your body need?
What is meant by a "balanced diet?"
What are the functions of the digestive system?
What occurs during digestion?
How are nutrients absorbed and wastes eliminated?
What is the principal role of the excretory system?
How do the kidneys clean the blood?
How do the kidneys maintain homeostasis?

SciLinks: Nutrition
SciLinks: The Excretory System

The Telltale Sample

On the first day of summer football practice, all players were required to have a physical.

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America's Obesity Problem

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