Chapter 13

Respiration and ExcretionPage 262

13:1 The Role of Respiration

A. Gases of Respiration1. Oxygen is brought into your body, and CO2 is

carried out of your body by your respiratory system.

2. Respiratory systems role is to exchange these gases.

3. Oxygen is used by cells in cellular respiration. 4. Cellular respiration: Oxygen and sugar combine ,

this creates energy for the body, carbon dioxide and water are formed.

5. Cellular Respiration Formulaa. C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy

i. C6H12O6= Simple Sugar

ii. 6O2= Oxygen

iii. 6CO2= Carbon Dioxide

iv. 6H2O= Water

6. Role of Respiratory System

Lungs

Deliver oxygen to the body

Needed by cells for cellular respiration

Remove CO2 from body

Given off by cells as waste product

B. Respiration in Animals1. Earthworms exchange gases through their skin. 2. Insects have large network of small tubes that carry air

to all body parts. 3. Frogs exchange gases through lungs and skin.4. Humans have lungs. 5. Respiratory systems have large surface area in order to

provide a surface for gases to diffuse into or out of the animals bodies.

6. The higher an organisms metabolism, the more efficient their respiratory system needs to be.

Need to Know Questions

1. Which gases are exchanged by the respiratory system?

2. Why is oxygen needed by our cells?3. Why do respiratory systems have large

surface areas?4. Explain why a bird would need a more

efficient respiratory system than human?

13:2 Human Respiratory System

A. Respiratory Organs1. Nose

a. Air enters noseb. Nose Hairs trap dust particles to prevent from

entering lungs.

2. Nasal Chambera. Large space above roof of your mouth.b. Warms or cools the entering air. c. Mucus is formed inside nose.

i. Mucus keeps air moist as it passes through the nose.

3. Epiglottisa. Small flap that closes over the windpipe when

you swallow. b. Prevents food or liquid from entering windpipe

when you are eating. (Video segment 1)

4. Trachea (windpipe) a. Tube about 15cm long that carries air to two

shorter tubes that lead into your longs.

5. Bronchia. Are two short tubes that carry air from the

trachea to the left and right lung.

6. Lungsa. Major organs of respiratory system. b. Exchange oxygen and carbon dioxide.

7. As bronchi enter lungs, they branch into thousands of smaller tubes.

a. Each of these tubes lead into tiny air sacs.

8. Alveoli (Video Segment two)a. Tiny air sacs of the lungs. b. Provide the large surface area for gases to pass into

and out of your blood. c. If all air sacs in a person’ s lungs were opened and

spread out they would cover an area equal to about 1/5 the area of a basketball court. (See pg 268)

2. Large Area provides a surface for gases to diffuse into or out of the blood or cells.

3. Frog= B; Earthworm= A, Fish D, Insect= E, Human (not Jamie)=C

B. Gas Exchange

Make Up of Air We BreatheGas Chemical

SymbolAir Entering

LungsAir Leaving

LungsOxygen O2 19.97 % 16.00%Carbon Dioxide

CO2 0.03% 4.00%

Nitrogen N2 80.00% 80.00%

1. Blood Capillaries around alveoli low in oxygen. 2. As you breath oxygen it fills each alveolus. 3. Oxygen passes out of the air sacs into the

blood by diffusion. a. Less moves out then brought in b/c some goes to

body cells.

4. Your lungs give off more CO2 then they receive. a. b/c carbon dioxide is formed as waste product by all

body cells during cellular respiration.

b. Blood arrives at the lungs, Carbon Dioxide diffuses out of the blood into the alveoli.

c. The carbon dioxide is then released into the air as your lungs exhale.

C. Breathing1. Most breathe in 12 to 16 times a minute. 2. Steps of the Breathing Process.

a. Diaphragm is relaxed. It is domelike and pushes upward. (see page 270 for all diagrams)

b. Space between lungs and inside of chest wall. As diaphragm pushes up against the lungs space gets smaller.

c. b/c lungs are soft they are squeezed as space gets smaller.

d. Air pushes out of the alveoli as the lungs are squeezed.

e. Diaphragm begins to contract. As it tightens up, it flattens and moves downward.

f. The space between the lungs and the inside of the chest becomes larger.

g. Lungs expand because space surrounding has increased.

h. Air is pulled into the alveoli as the lungs expand. This causes you to breath in.

13:3 Problems of the Respiratory System

A. A Breathing Problem1. Carbon Monoxide is an odorless, colorless,

poison gas sometimes found in the air. a. CO is more easily picked up by your red blood cells

than oxygen. b. CO comes from the burning of certain fuels. c. CO does not cause problems in open or well

ventilated areas, but in a closed area is deadly for humans.

B. Respiratory Diseases1. Pneumonia is a lung disease caused by bacteria,

virus or both. a. Microbes invade the alveoli and multiply. b. Causes lung tissue forms extra mucus. c. Mucus and pus fill the alveoli and cause difficulty in

breathing. d. Prevents oxygen from entering the lungs. e. Can be passed from one person to another.

2. Emphysemaa. Lung disease that results in the breakdown of

alveoli. b. Person seems to be always out of breath b/c

there are not enough alveoli to get oxygen into the blood.

c. Common cause is the breathing in of chemicals while smoking or from air pollution.

Answers to Study Guide page 75

1. Arrows should be shown leaving the alveoli and entering the capillary.

2. Drawing B should have the squares (Carbon Monoxide) leaving the alveoli and entering the capillary.

3. CO is picked up more easily by the RBC’s. If too much CO is inhaled, too little oxygen will be delivered to the person’s cells.

4. Drawing C shows alveoli filled with pus, liquid, and mucus.

a. What Disease may cause this to occur? 1. PNEUMONIA

b. Can oxygen (black dots) reach the capillaries surrounding these alveoli?

1. The alveoli are blocked with pus, liquid, and mucus. This prevents the Oxygen from getting into the blood.

5. Drawing D shows the alveoli of a person with emphysema.

a. How do these alveoli compare with those of a normal person?

a. Alveoli of a normal person have more surface area (see drawing A)

b. How is emphysema harmful?b. A person with emphysema is out of breath b/c

there are not enough alveoli surface area to get oxygen into the blood.

13:4 The Role of Excretion

A. Waste Removal1. Blood contains chemical wastes not needed by

body that could be harmful. a. Wastes could destroy cells and tissues. b. Cause fever, poisoning, or even death.

2. Wastes made by blood cells or undigested food. 3. Excretion is the process of removing waste from

the body. a. Solid wastes removed by digestive system.

b. Liquid wastes removed by excretory system.

4. Urea is a waste that results from the breakdown of body protein.

a. Poisonous and must be removed from the body. b. Picked up from cells by blood and carried to kidneys. c. The KIDNEYS are the most important organ in the

excretory system.

5. Animals without kidneys (sponges, jellyfish)a. Waste passes out of cells directly into the water they live. b. Earthworms use a pair of tubes in each body segment

that connect the inside of the animal to the outside.

B. Human Kidneys 1. Each human body starts with two kidneys, each

about as big as a fist. 2. Filters waste from blood. 3. During one day your kidneys filter up to 200 liters

of blood. 4. Kidneys are hooked up to blood vessels.

C. Steps of Blood through kidneys. 1. Blood carrying wastes move through bodies

arteries. 2. Small arteries bring blood to be filtered into each

kidney. 3. Kidneys filter urea from blood. 4. Filtered blood leaves kidneys through veins.

a. Blood is now free of waste.

5. Blood in veins is taken to the heart and other parts of the body.

6. Wastes from blood leave each kidney through a URETER.

A. URETER is a tube that carries waste from kidney to urinary bladder.

7. Urinary Bladder is a storage for liquid wastes from the kidney.

8. The URETHA is a tube that carries liquid waste from bladder to outside the body.