* It can take many forms * Occurs when there is damage to the heart or arteries * Usually caused by plaque buildup * Atherosclerosis is a form of cardiovascular disease. It is when plaque builds up on the inside walls of the arteries. Atherosclerosis

* High fat diet * High salt diet * Low amount of exercise * Smoking * Family history * Stress * Being overweight

* What can happen to our cells if there is too much plaque build up?

* We can prevent this by…

The Respiratory System

-Respiratory System Note -Activity: How do you breathe? -(Model lungs and diaphragm)

* The respiratory system is an ­organ system that allows humans to breathe * The purpose of the respiratory system is to provide oxygen for the cells and remove carbon dioxide * The respiratory system is made up of the lungs, trachea, bronchi, and other structures that help the body intake oxygen and release carbon dioxide

Mouth or Nasal Cavity  Pharynx  Trachea  Bronchi  Bronchioles  Alveoli

* Cilia and mucus line the walls of the trachea and bronchi and trap bacteria and dirt that are in the air. They sweep them upwards into the throat where the mucus is either swallowed or coughed up

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* Breathing involves inhaling (breathing in) and exhaling (breathing out) * When you breathe in, muscles attached to your ribcage and a large muscle called the diaphragm contract which makes the chest larger

* When the chest is larger, air filled with oxygen is pulled into the lungs * When the ribcage muscles and diaphragm relax, the chest becomes smaller and the air and carbon dioxide are pushed out (exhaled)

* The oxygen in the air we breathe needs to get to our cells. It does this through gas exchange. * When the air enters your lungs, it travels to very small air sacs called alveoli which are surrounded by tiny blood vessels called capillaries

* When we breathe in, the amount of oxygen in the alveoli is greater than the amount of oxygen in the capillaries. The oxygen moves by diffusion into the blood. * At the same time, the blood has more carbon dioxide than the alveoli so the carbon dioxide moves into the alveoli * The oxygen that entered the blood moves around the body to the cells that need it. The carbon dioxide that entered the alveoli is released when we exhale.

THE EXCHANGE OF CARBON DIOXIDE FOR OXYGEN IN THE BLOOD IS THE REASON WHY WE BREATHE! * Video:

* Breathing happens naturally but you can also control it * Many people can hold their breath, but once there’s too much carbon dioxide in the blood, you HAVE to breathe!

* When carbon dioxide builds up in the blood, it sends a message to the brain. The brain then sends a message to the ribcage muscles and diaphragm to contract. This causes the chest to get bigger and allow oxygen filled air into the lungs!

* Asthma is a ­­­­­­­­­­­­­respiratory condition which makes the airways extra sensitive. * Certain particles in the air can cause the airway to become red and swollen. When this happens, a lot of ­­mucus­ is produced which makes the airways narrower. This makes breathing difficult! * The muscles around your airway tighten and make it even more difficult to breathe. * Medication can help to reduce the swelling which makes breathing easier. Normal airways Airways of a person without asthma Airways of a person with asthma - redness and swelling (inflammation) Airways of a person with asthma - tightened muscles (bronchospasm)

* Bronchitis occurs when the bronchi become swollen. * This means that the walls of your bronchi are swollen and filled with extra sticky mucus. * Airflow into and out of your lungs is partly blocked because of the swelling and extra mucus in your bronchi. * Bronchitis can go away on its own or can be treated with medication.

* Smoking destroys the tiny hairs (cilia), which line the upper airways and protect against infection. * When your lungs' natural cleaning and repair system is damaged, germs, dirt and chemicals from cigarette smoke stay inside your lungs. This puts you at risk for chronic cough, chest infections, and lung cancer.

* The alveoli are like stretchy balloons. As you breathe in, your alveoli help you absorb oxygen into your body, and as you breathe out, alveoli help get rid of the waste gas carbon dioxide. * Smoke damages your lungs so much that your alveoli become less stretchy. This means it's harder for your lungs to take in the oxygen you need and harder to get rid of carbon dioxide.