All the cells of your body need oxygen to stay alive. So you have to breathe air into your body. Air goes in your lungs.

It is talking about breathing in(inhaling) and out (exhaling), so oxygen can pumped through your body and carbon dioxide can be removed from the blood stream.

Breathing is divided into two parts:-  Ventilation:-Getting the air into and out of the lungs.  Gas exchange:- getting the gases to move into or out of the blood

Gas exchange is a two way process:-  Waste gases are removed  Oxygen is absorbed

How many lungs do your have?  Our lungs consist of two. The left lung and the right lung In what part of the body are they?  chest

 These bronchi tube split up like tree branches, and gets smaller and smaller inside your lungs. The air will flow to your bronchi tubes into the bronchiole. These tubes are getting smaller and smaller until they finally end with tiny small sacs called the alveoli.

 Your alveoli are tiny air sacs that fills up air/oxygen when you breathe in. Your alveoli is surrounded by many tiny blood vessels capillaries. The walls of the capillaries need to be thin so that oxygen or carbon dioxide can pass through them.

Nasal Passage Bronchi Tubes Alveoli (air-sacs) Thin-walled blood vessels called capillaries Very thin cells line the alveoli so that O 2 and CO 2 can pass in and out of the blood. Bronchioles pass air to and from your alveoli. The Trachea is held open by partial rings of cartilage. Tongue Pharynx

What is the job of the diaphragm?  It takes an important part in breathing.

When you breathe in:-  Diaphragm contracts  Muscles between your ribs move your ribcage up and out.  Your diaphragm moves down and becomes flatter  The extra space in you lungs fill with air.

When you breathe out:  Your ribs move down  Your diaphragm curves up again  There is less space inside your chest so air is pushed out

The space inside your lungs when you are breathing in:  Shallow breath 2000 cm3  Deep breath 4500 cm3 The space inside your lungs when you are breathing out:-  1500 cm3  This means that there is 1500cm3 of air that you can’t breathe out.

 Gas exchange takes place in the alveoli  Carbon dioxide is more in the capillaries so they move out.  While oxygen is more in the outside in the alveoli than in the red blood cells.  The gases always move where there is higher concentration to lower concentration (difffusion).  The difference in the concentration means that oxygen diffuses into the blood and carbon dioxide diffuses from the blood into the alveoli. This movement of gas is called gas exchange

oxgenated blood is bright red in color and travels towards the heart from the lungs where as deoxygenated blood is darker in color and travels back to the lungs from the blood capillaries to be resupplied with oxygen.

ASTHMA:- Asthma is the inflammation of the small airways of the lungs that causes less air to pass through. The bronchioles becomes narrower because the lining swells. Also, muscles in the bronchiole walls contract or shorten

Difficulty in breathing or shortness of breath. Patient gets wheezy (producing a sound when you are breathing) often especially on a cold day). Patient also coughs or only symtom in some children.

3-5% of adults 7-10% of children Most of them have wheezing attacks Some have chronic short of breath. It can give a sudden attack and can become dangerous if the air flows cant pass through properly.

When Brandon feels his chest go tight, he uses an inhaler. He breaths in a drug from the inhaler. The drug relaxes the muscles in the walls of his bronchioles. So, the tubes widen and he can breathe more easily.

It is important that she stays calm and uses his inhaler straight away. Sometimes his breathing gets very difficult and he has an asthma attack.

Plants also need to exchange gases. They need respiration in the same way as animals / human but they also need carbon dioxide for photosynthesis.

The air outside the leaf is free to move into the air spaces inside the leaf, through stomata. When the plant is photosynthesising, the carbon dioxide diffuses into the mesophyll leaf cells and oxygen diffuses out.

In respiration (during the night) the oxygen diffuses into the cells and carbon dioxide diffuses out. When the plant is not photosnthesising i.e. when it is dark.

The leaf has the same adaptations as humans/animal’s lungs. There is large surface area for diffusion inside the leaf and a short distance for the gases to move.