Begin

The Respiratory System

Weird.

#1 First, a Review

•Function = job•Homeostasis = equilibrium for the body. Your body tries

to maintain a healthy balance of all things.•Stimulus/response = how your body reacts to situations

and messages that require action.

Easy. No heart attacks this time,

right?

Sure, Joe…no heart attacks. No other promises, though.

#2 Respiratory System Overview

Why do we need to breathe?

If you say, “because we need oxygen to live,” then explainwhy we need oxygen.It’s because the sugar you eat (glucose) that serves as the primarysource of energy for your body really acts as a storage box of energy.To get that energy free from the glucose so that your cells can use it,your cells carry out a process called respiration that involves reactingglucose with oxygen to free up energy.

You get the glucose from digesting food, and yep, you get the oxygen from breathing. THAT’s why you have to breathe to stay alive.

Glucose + O2 water (waste) + CO2 (waste) + ENERGY!

Cellular Respiration

#3 Resp. System Overview, Cont.

The respiratory system’s main job is to exchange gases inthe lungs.

The whole system… All your cells are doing…

#4 FUNCTIONS of the Resp. Sys.

1. Gets oxygen from air for body’s cells (inhaling)

2. Gets rid of carbon dioxide waste from cells (exhaling)

3. Allows us to speak

Pretty important stuff for oursurvival & “advancement” as asociety, huh.

#5 How do we actually breathe?

What actually causes air to fill our lungs when we breathe in???

Well, you see, the contraction of the diaphragm muscle in the mid-torso causes an expansion of

volume in the lung cavities…this expansion creates a pressure gradient, or vacuum, that acts as a FORCE

pulling air into the lungs.

In “English,” the diaphragm muscle (in red) pullsdown on the lungs, making them bigger, which createsempty space (a vacuum) that air rushes in to fill. Whenwe exhale, the diaphragm just pushes up on the lungs,like when you squeeze a balloon to let the air out quicker.

Nose/Sinuses

#6 STRUCTURES of the Respiratory System

The respiratory system is laid out as a tract. A tract is a series of organs that are arranged one after another. The digestive tract is another example. Let’s start as air comes in while you inhale.

Be sure to label your sketch on the back of your notes as we go through these organs!

1. Nose/sinuses – make air warm, moist, and clean (hairs/mucus).Sinuses affect your voice.

The nose is just better at preparingair for your lungs than your mouthis. Breathing through your nose isusually just flat-out better.

#7 Structures, contd.Once cleaned & prepped by your nose, the air continues back towardyour throat.2. Pharynx – throat…both food and air pass. Epiglottis keeps you fromchoking on food/drinks.

3. Larynx – vocal cords: vibrate to make noise as you exhale. Incombination with the different shapes your tongue, lips, etc. can form,you have the ability to make hundreds of different sounds.

Place your Finger on your larynx and make thesesounds: s, z, p, b, f, v

#8 Structures, contd.Air continues on its journey to the lungs…

4. Trachea – windpipe. This is held open by rings of cartilage so thatit doesn’t collapse shut when you inhale. The trachea splits into two…

5. Bronchi/bronchioles – smaller passages that split heading into thelungs.

Well, now we’regetting closer toair’s finaldestination.

#9 Structures, contd.Air is now finally inside the…

6. Lungs – spongy organs filled with alveoli—tiny air sacs that havetwo jobs:

a. stuff O2 into capillaries (where RBCs will carry it to body)b. allow CO2 into bronchioles (where it can be exhaled out)

bronchioles end as alveoli &are surrounded by capillaries

gas exchange between alveoliand capillaries

#10 Structures, contd.And of course, since the organs make a tract, air just reverses throughthem as the diaphragm pushes and you exhale.

Every time you exhale,you release waste gases intothe air, or into a bubble, intoa trumpet, or whatever.

Plants love it though…ourwaste is their treasure!

#11 DISORDERS of the Respiratory System

Boy, what an important set of organs for your survival. No wonderyou can hold your breath only so long before your body says, “enough,you’re being foolish” and forces you to breathe despite your efforts.

So, take care of your respiratory system. Seriously. Let’s see what canhappen if it doesn’t function properly or if you abuse what you were given.

I don’t like how this sounds…what are

you gonna do to me?

Let’s say that Joe has been a chain-smoker for many years…

#12 Disorders, contd. Smoking kills little hairs inyour respiratory tract thatmove mucus around. Thiscauses that annoying “smoker’s cough” that youoften hear. It causes anextreme shortness of breathcalled emphysema, whichwould affect your daily life. And of course, it often leads to…

#13 Disorders, contd.Man, I’m tired. I’ve gotta take a

break.

Smoking is probably the mostharmful way in which you candamage your respiratory systemon purpose. Avoiding its problemsis easy…just don’t start. It might’ve seemed cool &rebellious 20 years ago, but nowmost people realize it’s just dumb.Let’s give Joe a break—he kicks the habit.

#14 Disorders, contd.There are several disorders that aren’t necessarily somebody’s “fault”for having. You’ve heard of at least a couple of these, I’m sure.

1. Bronchitis – “itis” means “inflammation or infection of…” So, thisis some sort of irritation of your bronchial passages often resulting incoughing and maybe phlegm. Your doctor can find which medicinewill kick this to the curb. *hack*

*cough*#@$%!*hack*

#15 Disorders, contd.2. Asthma – there are lots

of causes of asthma, and some pretty easy-

to-use treatments. Asthma occurs when your bronchial passages

inflame, causing them to shrink up and make breathing difficult.

#16 Disorders, contd.One condition that genetic researchers are still trying to cure is called:

3. Cystic Fibrosis – This is a build-up of thick mucus in the lungs…thismucus must be loosened and coughed up very often. Cystic Fibrosisis genetic, and appears almost instantly in newborns. The problems thismucus causes the lungs and digestive system usually results in prettyserious health concerns as the people enter their 20s and 30s.

#17 ReviewJust like last time, we’ll review the Respiratory System by seeing whatwould happen if it stopped functioning.

1. Gets oxygen from air for body’s cells (inhaling)

Joe would quickly go unconscious as his brain cells fall asleep and he’d die within 5 to 30 minutes.

2. Gets rid of carbon dioxide waste from cells (exhaling)

Joe would build-up CO2 in his blood, slowly poisoning himself. He’d get a bad headache and feel very tired until he fell into a comaand died of blood poisoning as his organs shut down one by one.

3. Allows us to speak

Joe would not be able to communicate as easily, and would need tolearn sign-language or carry around paper & pen everywhere.

#18 ReviewHow does the Respiratory System maintain homeostasis?

By maintaining the proper amounts of oxygen and carbon dioxidein your blood, that’s how.

Stimulus : Response(something you respond to) : (the response)Tiring muscles while exercising : faster breathing rate to supply more

oxygen to those muscles

#19 And That’s…