Human body

HUMAN BODY

Breathing system

-Breathing is the process of taking air in and out of the body.

-The process of breathing in and out is called respiration.

-The two repiratory gases are

i Oxygen

ii Carbon dioxde

-Oxygen is breathed into the body and is generate energy Breathing in is called inhalation.

Carbon dioxide is breathed out of the

Carbon dioxde body as a waste gas Breathing out is called exhalation

Main parts of the breathing system

Nose

brachea

Branchi

lungs

Diaphram

Functions of the main parts of breathing system

Nose

-It is an exteranal organ of the body with two openings called nostrils

-In the nostrills, there are small hairs that trap dust and other particles

-It has mucus that helps to moisturen the air

-It has small blood vessel, that help warming the

air

Therefore air is cleaned, warmed and moistened in the nose. Trachea

It is also known as windpipe

It connects the nose and the bronchi

It has C-shaped rings called cartilage which help to keep it open atall times This allows our air to pass through easily

The trachea mucus that trap and kill germs in the inhaled air entering the trachea by speacial flap called epiglottis

Bronchi

They are two in number and they are branch from the trachea

The branch supply air into finner bubes called bronchioles found in the lungs

The bronchioles are connected to the air sacs alveoli

The air sacs in the gaseours exchange lungs

These are spongy organs situated in the chest. There are two lungs one on the left and the other on the right.

Lungs have millons of air sacs allow exchange of respiratory gases.

Oxygen gets in the blood while carboo axide gets out of the body blood

Diaphragm

This is a sheet of muscles that separates the lungs and the abodmen

The diaphragm allows Lungs to expand and contract

==stages of breathing in==

The ribs move upwards and outwards.

The diaphragm moves downwards and flattens

The volume of the carity increases causing the Lungs to expand and the pressure to decrease

Air enters the lung though the nose

==Stages of breathing out,==

The ribs move down wards and inwards

The diaphragm moves upwards and becomes dorm shape.

volume of the chest cavity ddecreases forcing the lungs to contract and ppressure to ncrease

Air is pushed out of the lungs and Latery breathed out though the nose

==Parts of model== ==Part of the breathing== straw trachea

Plastic bottle rib cage

Balloons lungs

Rubber sheet diaphragm

When the rubber sheet is pulled down wards by the string the balloons are filled with air.

When the string is pulled upwards the ballows get deflated