At a Glance

Life on Earth Chapter 23 Nutrition, Digestion and Excretion
At a Glance

Nutrition: The primary sources of energy are carbohydrates and fats.
Lipids include fats, phospholipids, and cholesterol.
Carbohydrates, including sugars and starches, are a source of quick energy.
Proteins, composed of amino acids, perform a wide range of functions within the body.
Minerals are elements and small inorganic molecules required by the body.
Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Lipids include fats, phospholipids, and cholesterol.
Carbohydrates, including sugars and starches, are a source of quick energy.
Proteins, composed of amino acids, perform a wide range of functions within the body.
Minerals are elements and small inorganic molecules required by the body.
Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Carbohydrates, including sugars and starches, are a source of quick energy.
Proteins, composed of amino acids, perform a wide range of functions within the body.
Minerals are elements and small inorganic molecules required by the body.
Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Proteins, composed of amino acids, perform a wide range of functions within the body.
Minerals are elements and small inorganic molecules required by the body.
Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Minerals are elements and small inorganic molecules required by the body.
Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Vitamins are required in small amounts and play many roles in metabolism.
Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Nutritional guidelines help people obtain a balanced diet.

The Challenge of Digestion

Human Digestion
The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.
The Challenge of Digestion
Human Digestion: The mechanical and chemical breakdown of food begins in the mouth.
The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; The esophagus conducts food to the stomach, where digestion continues.
Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Most digestion occurs in the small intestine.
Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Most absorption occurs in the small intestine.
Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Water is absorbed and feces are formed in the large intestine.
Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Digestion is controlled by the nervous system and hormones.

The Functions of the Urinary System

The Human Urinary System
Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.
The Functions of the Urinary System
The Human Urinary System: Urine is formed in the kidneys.
Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; Blood is filtered by the glomerulus.
The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; The blood filtrate is converted to urine in the nephron.
The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; The loop of Henle allows urine to become concentrated.
The kidneys are important organs of homeostasis.; The kidneys are important organs of homeostasis.

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