1. Explain why swallowed food does not normally enter the airway leading to the lungs.

  2. What is the importance of enzymes during digestion?

  3. Describe the functions of the pancreas.

  4. How is the structure of the villi adapted to their function?

Think Critically

  1. Infer Individuals who have had part, or even all, of their stomachs removed can survive if fed predigested food. Could these individuals also survive without a small intestine? Explain.

  2. Predict Suppose that your doctor prescribed an antibiotic that killed all the bacteria in your body. What effect would this have on your digestive system?

30.4 The Excretory System

Understand Key Concepts

  1. Which of the following is the basic functional unit in a kidney?

    1. nephron.

    2. glomerulus.

    3. Bowman's capsule.

    4. loop of Henle.

  2. Urine is excreted from the body through the

    1. ureter.

    2. urinary bladder.

    3. urethra.

    4. renal vein.

  3. What is the role of the skin in excretion?

  4. What materials are filtered from blood in the kidney? What materials do not leave the bloodstream?

  5. How is the water-regulating activity of the kidney controlled?

Think Critically

  1. Apply Concepts Explain why kidney failure can be a fatal condition.

  2. Infer When there is too much fluid in the blood, the heart must pump harder. Diuretics are substances that stimulate the kidneys to remove more fluid from the body. Why do you think diuretics are used to treat high blood pressure?

solve the CHAPTER MYSTERY

Rugby players.

THE TELLTALE SAMPLE

For centuries, people have used urine for clues to health and disease. The Greeks, for example, knew that diabetics had excessive sugar in their urine and called the disease diabetes mellitus. Mellitus is the Greek word for honey.

  • Physical Examination During this step, the color and clarity are examined. The shade of yellow indicates the amount of water being released by the kidneys. Urine of a color other than yellow could indicate the presence of blood. Or, it could simply indicate someone has eaten a lot of beets. Urine should be clear, rather than cloudy.

  • Microscopic Examination The presence of mucus, white blood cells, or microorganisms in urine indicates a probable infection. Cloudy urine may also be caused by crystals, which could indicate kidney stones or a metabolic problem.

  • Chemical Examination Hundreds of chemical tests can be performed on urine. Chemical dipsticks are used that change color in the presence of other chemicals. These tests can reveal a lot about kidney function, liver function, and overall homeostasis in the body.

  1. Infer How does urine reveal so much about the health of the human body?

  2. Form an Opinion Most drug urine tests performed for schools do not test for alcohol or tobacco. Why do you think this is the case? Do you agree or disagree? Explain.

  3. Connect to the Ketones are a product of the breakdown of fat for energy. Ketones in the urine can be an indication of diabetes. Why do you think this is?

End ofPage 891

Table of Contents

Miller & Levine Biology
About the Authors
Changing the World of Biology Education
Contents
Diversity of Life: A Visual Guide DOL•1–DOL•64
Labs and Activities
Features
UNIT 1 The Nature of Life
1 The Science of Biology
2 The Chemistry of Life
Unit Project
UNIT 2 Ecology
3 The Biosphere
4 Ecosystems and Communities
5 Populations
6 Humans in the Biosphere
Unit Project
UNIT 3 Cells
7 Cell Structure and Function
8 Photosynthesis
9 Cellular Respiration and Fermentation
10 Cell Growth and Division
Unit Project
UNIT 4 Genetics
11 Introduction to Genetics
12 DNA
13 RNA and Protein Synthesis
14 Human Heredity
15 Genetic Engineering
Unit Project
UNIT 5 Evolution
16 Darwin's Theory of Evolution
17 Evolution of Populations
18 Classification
19 History of Life
Unit Project
UNIT 6 From Microorganisms to Plants
20 Viruses and Prokaryotes
21 Protists and Fungi
22 Introduction to Plants
23 Plant Structure and Function
24 Plant Reproduction and Response
Unit Project
UNIT 7 Animals
25 Introduction to Animals
26 Animal Evolution and Diversity
27 Animal Systems I
28 Animal Systems II
29 Animal Behavior
Unit Project
UNIT 8 The Human Body
30 Digestive and Excretory Systems
31 Nervous System
32 Skeletal, Muscular, and Integumentary Systems
33 Circulatory and Respiratory Systems
34 Endocrine and Reproductive Systems
35 Immune System and Disease
Unit Project
A Visual Guide to The Diversity of Life
HOW TO USE THIS GUIDE
THE TREE OF LIFE
Bacteria
Protists
Fungi
Plants
Animals
Appendices
Appendix A Science Skills
Appendix B Lab Skills
Appendix C Technology & Design
Appendix D Math Skills
Appendix E Periodic Table
Glossary
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q, R
S
T
U
V
W
X, Y, Z
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Credits
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