Human Breathing System

D. Crowley, 2007

Learning objectives:

1. Must say what the job of the lungs is and name the main parts

2. Should describe the special features the lungs have to do their job really well

3. Could explain how the alveoli work

To take in _______________ for cellular respiration to produce ___________ and

To take out ______________________ as a waste product of cellular respiration.

OXYGEN

Carbon Dioxide

ENERGY

STRUCTURES

Nose Mouth

Larynx/Vocal chord

Lungs

Bronchi

Diaphragm

Pharynx

Trachea/windpipe

Bronchi

Bronchiole

Alveoli

Where air enters or exit

the body. Inside it has hairs to

filter dust particles

Fastest way to get air into lungs but no

air or bacteria filter

As air passage to trachea. Here is where we produce our voice

Spongy structure that has a function for the place of gas exchange. Its volume can expand during inhalation

Air passage to alveoli

Large flat muscle that control breathing process

Air and food

passage

Air passage that is supported by cartilage rings

Branch of

bronchi

Tiny air sacs. This

is the place of

gas exchange.

Two types of Ventilation

How are inhaled and exhaled air different?

As you breath, your lungs fill with air again and again. This is called ventilation. Air is inhaled (taken in) into the lungs. Some of the oxygen is removed and passes into the blood. Carbon dioxide, a poisonous waste gas produced in respiration, passes out of the blood and into the air in the lungs. This is exhaled (breathed out). The composition of gases in inhaled air and exhaled air is different.

% in inhaled air % in exhaled air

Oxygen 21 17

Nitrogen 78 78

Carbon Dioxide 0.04 4

Other Gases 0.96 0.96

Water variable saturated

Three type of respirationExternal respiration – Exchange of gases between ____________ and _________ tissue – Occurs in ___________ of lung tissue

atmosphere blood

Alveoli

Three type of respirationInternal respiration – Exchange of gases between _______ and _______ of the body

cellBlood

This happens when red blood cell transport O2 to all cells in the body’s tissues.

Three type of respiration

– Utilization of ___________ to produce _______ from sugar in the cell

Sugar [GLUCOSE]

+ O2

Inside mitochondria

Energy source for cells

H2O + CO2

+

O2ATP energy

Gas Exchange

It is vital we get as much oxygen as possible during every breathe, as well as remove as much carbon dioxide as possible

In the lungs, oxygen travels to thousands of tiny air sacs called alveoli - covered with tiny blood vessels

The alveoli are adapted to make gas exchange in lungs happen easily and efficiently (Not more, just faster)

OXYGEN AND CO2 DIFFUSION IN THE LUNGS

Alveoli – adaptations to speed up diffusion in gas exchange Alveoli give the lungs a really big surface area Alveoli have moist, thin walls (just one cell thick) called the

alveolus epithelium Alveoli have a lot of tiny blood vessels called capillaries –

continuous blood flow

Cilia

There are also specialised cells in the lining of the breathing tubes which produce a sticky mucus to trap dirt and microbes

Specialised cells called cilia help to move this mucus out of the lungs

Smoking can damage these delicate cells (hot smoke and tar) and they are less effective

This is why smokers cough a lot, trying to move this mucus

Cilia

Science Quiz

When?Monday, 6th April 2015

What to study?Cells and Respiratory System