breathing system exposition

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The Breathing System

Science



Cartilage and the trachea

Basics of breathing

Inside an alveolus

Breathtaking features

Bronchi and the lungs

Contents

Summary


Oxygen (O2)

Carbon Dioxide (CO2)

Humans breathe to ensure that oxygen enters the bodyand that carbon dioxide leaves the body.

The breathing system

Basics of breathing


Let us now look at the structure of the breathing system.The human body can be divided into three regions.

The breathing system is found in the thorax.

THORAX

ABDOMEN

HEAD

Parts of the body involved


Well, let us start where air enters the system… Air enters through either the mouth or the nostrils.

It does not matter through which opening the air enters because the oral and nasal cavities are connected.

mouth nostril nasal cavity

oral cavity

What it looks like inside


As the air passes through the nasal cavity, the air is smelt, warmed, filtered and moistened slightly.The air meets at the pharynx, a junction at back of the oral cavity.

trachea

gullet

The pharynx


As well as being adapted on its outer surface, the trachea shows adaptations on its inner lining.

If we look closely at the inner surface of the trachea…

ciliated epithelial cells

The trachea

trachea


produce a sticky liquid - mucus

tiny hairs called cilia

Ciliated epithelial cells

Ciliated epithelial cells


In reality, the lungs are different in shape. Here is a more accurate diagram.

bronchiole

cartilagetrachea

right bronchus

location of the heart

Diagram of a lung

Right Lung

pleural membrane


When you breathe in (inhale), your hands move up and outwards.

When you breathe out (exhale), your hands move down and inwards..

Take a breath


When we inhale, our lungs fill with air.

As they fill, they become enlarged.

The ribs must then move upwards and outwards to make more room in the thorax.

The overall effect of this is that our chest expands.

Inhaling: chest expansion


Your diaphragm is located beneath the lungs, which means that it separates the thorax from the abdomen.

It is a sheet of muscle that spans the width of the body.

inhaling

The diaphragm

Before we inhale, it is found in a domedome shape.

As we inhale, it contracts and flattensflattens.

The result of this change in shape is a change in the volume of the thorax.



Cartilage and the trachea

Basics of breathing

Inside an alveolus

Breathtaking features

Bronchi and the lungs

Contents

Summary


Multiple choice section


Breathing in or out?


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breathing system exposition

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