Table of Contents

The Respiratory System

The Excretory System

Managing Materials in the Body

Resources

Pearson online activity

Excretory/Urinary System

Respiratory System

Asthma

What is the Role of the Respiratory System? Pg. 472

• Your respiratory system moves air

containing oxygen into your lungs and

removes carbon dioxide and water from your

body.

• Your lungs and the structures that lead to

them make up your respiratory system.

• The oxygen is used by body cells during

cellular respiration, in which the chemical

energy in glucose is released.

The Respiratory System Fig. 1 pg 473

Systems Working Together

Describe how each system provides cells with materials needed for cellular respiration. Then tell how cellular respiration helps the body maintain homeostasis.

Breathing Structures pg. 474

Air, containing oxygen, enters the body through the nose and then passes into the pharynx, or throat.

It then passes into the trachea, or windpipe, where tiny hairlike extensions known as cilia sweep mucus up to the pharynx.

Air then moves into the bronchi, which are passages to the lungs, the main organs of the respiratory system.

The lungs consist of alveoli, which are tiny sacs through which gases are

exchanged with the blood.

Did You Know? Pg. 474

• Some particles can irritate the lining of your nose or throat, causing you to sneeze.

• This powerful force shoots the particles back into the air. The wet spray from a sneeze can travel up to 160 kilometers per hour and spread more than one meter away from the sneezer!

Structures of the Respiratory System

Particles in the air are filtered out as the air moves through the respiratory system. What does each part of the respiratory system do?

Assess Your Under.

The Respiratory System fig. 3 pg.475

What Happens When You Breathe? Pg 476

Breathing is controlled by rib muscles, as well as a large dome-shaped muscle called the diaphragm.

When you breathe, your rib muscles and diaphragm work together, causing air to move into or out of your lungs.

This airflow leads to the exchange of gases that occurs in your lungs

The Respiratory System fig 4 pg. 476 The Breathing Process

When you inhale, air is pulled into your lungs. When you exhale, air is forced out. What happens to your muscles

when you breathe?

Speech & Vocal Cords pg 477

The air involved in breathing also makes speech possible.

Two folds of connective tissue, known as vocal cords, stretch across the opening of the larynx, or voice box. The flow of air along with the contraction of muscles causes the vocal cords to vibrate, thereby producing sound.

Gas Exchange pg. 478-479

After air enters the alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood.

Similarly, carbon dioxide and water pass from the blood into the air in the alveolus. This whole process is called gas exchange.

Gas exchange is aided by the tremendous surface area of the many alveoli in the lungs.

The Respiratory System Fig. 5 pg 478

Gas ExchangeGases move across the thin walls of both alveoli and capillaries. Determine the gas being exchanged and describe where it is coming from and moving to.

Assess your Und. Pg 479

Breathing and SpeakingWhat are the steps involved in speaking?

The Respiratory System pg. 477

Ch. 12.4

Excretory System

Urine is made up of water, organic solids, and inorganic solids. The organic solids include urea and acids. The inorganic solids include salts and minerals. The solids are dissolved in the water.

What is the percentage of urine that is solids? What is the percentage of solids that is urea?

The Excretory System Do the Math. Pg. 481

What is the Role of the Excretory System? Pg. 481

• Excretion is the process of removing waste.

• The excretory system collects the wastes that cells produce and removes them from the body.

The system consists of:

1. the kidneys

2. ureters

3. urinary bladder

4. urethra

One waste the body must eliminate is urea, which is a chemical that comes from the breakdown of proteins.

Structures that Remove Urine pg. 482

Urea, water, and other wastes are eliminated in a fluid called urine.

Urine is produced in the kidneys- which are the major organs of the excretory system

Nephrons in the kidneys filter materials from the blood. They remove the wastes in urine and return any needed materials back to the blood.

Urine then flows from the kidneys through two narrow tubes called ureters, which carry urine to a saclike organ known as the urinary bladder. Urine leaves the body through a small tube called the urethra.

Removing UrineUrine is produced in the kidneys and then removed from the body.

The Excretory System pg. 482

Kidney

Ureter

Urinarybladder

Urethra

The Excretory System Fig. 2 pg. 483

How the Kidneys Work

Most of the work of the kidneys is done in the nephrons.

Assess Your Under.

How Does Excretion helps to maintain homeostasis? Pg. 484

• Excretion helps to maintain homeostasis by keeping the body’s internal environment stable and free of harmful levels of chemicals. The organs of excretion include:

kidneys, lungs, skin, and liver

The kidneys filter blood. They regulate the amount of water in the body.

The lungs and skin also remove wastes. The lungs, for example, remove carbon dioxide and some water.

The skin removes some water and urea through perspiration.

The liver produces urea and breaks down some wastes into forms that can be excreted.

What is each organ’s role in excretion? Pg. 485

The Excretory System Fig. 3 pg. 484

The Excretory System pg. 486-487

Moving Things AlongHow do systems of the body move and manage materials? Identify the main function of the respiratory system, the excretory system, the circulatory system and the digestive system.