Gas+Exchange

Respiratory System:

Functions:

- Moves oxygen from the external (outside) environment into the body. - Removes CO2 and H2O from the body (waste).

- Oxygen is needed for the energy-releasing chemical reactions that happen inside our cells (cell respiration). Without oxgen, your cells cannot "burn" enough fuel to keep you alive.
 * Taking In Oxygen:**

RESPIRATION is the process where energy is released from glucose inside the cell with the use of oxygen.
 * RESPIRATION x BREATHING:**

BREATHING is the movement of the air going inside our body and going out again.

Reviewing: you need to breathe to get oxygen in your blood, so it can transport the oxygen to your cells where it will help break the sugars and release ENERGY!

Respiration produces H20 and CO2. The lungs take the CO2 from the blood, through the aveoli, and is exhaled from the body. Water, on the other hand, can be used to control temperature (homeostasis) and sometimes, it simply leaves the lungs (as vapor).
 * Removing CO2 and H20:**

1. Nasal/Mouth Cavity //>> hair filter the air/nasal chamber makes the air moist and warm to prevent irritation in your respiratory tract. <> where voice box is along with vocal cords <> Mucus, a sticky substance traps most polluted materials from the external environment and the cilia, hair-like projections each cell has, sweep them back to the larynx where it goes down to the stomach and is destroyed by the hydrochloric acid. < Aveoli //>>sacs covered with capillaries where gas exchange occurs<<//
 * The Path of Air:**

after air enters an alveolus, oxygen passes trough the wall of the alveous and then through the capillary wall into the blood. Carbon Dioxide and water pass from the blood into the alveoli and get released when you exhale.
 * Gas Exchange**

What are alveoli? -They are tiny sacs surrounded by capillaries in which gas exchange occurs -They are moist to facilitate gas exchange (molecules move easily in fluid) -They have a single celled wall to facilitate gas exchange (thin wall = molecules move faster/easily) -We have about 300 million of them -They are able to expand to allow more air in

inhaling: diaphragm contracts--->rib cage expands--->air comes in exhale: diaphragm relaxes--->rib cage goes back to normal size/contracts--->air goes out
 * How do we breathe?**

When you breathe, the actions of your rib muscles and diahragm expand or contract your chest. As a result, air flows in or out.

The diaphragm is a muscle connected to the ribs vocal cords can be found in the larynx, they are flaps of tissue that vibrate and create sound.
 * Vocal cords**


 * Smoking and Your Health** - Rich Choi

More than 4,000 different chemicals are in tobacco. Tar, carbon monoxide, and nicotine would be the three main bad substances of tobacco. __Tar__ - Tar is the dark, sticky substance that forms when tobaco burns. Tar makes cilia clump together so they can't function to prevent harmful materials from getting into the lungs. __Carbon Monoxide__ - When substances are burned, a coloress, odorless gas called carbon monoxide is produced. When carbon monoxide binds to hemoglobin, it takes the place of some oxygen that the red blood cells normally carry. __Nicotine__ - Nicotine is a stimulant drug that increases the activities of nervous system and heart beat and blood pressure. Over time, nicotine produces an addiction. Over time, smokers can develop chronic bronchitis, emphysema, lung cancer, and atherosclerosis. __Chronic Bronchitis__ - Bronchitis is an irritation of the breathing passages become narrower than normal and may be clogged with mucus. If it continues over time, it become chronic bronchitis, which cause permanent damage to the breathing passages. __Emphysema__ - Emphysema is a serious disease that destroy lung tissue and causes breathing difficulty. People with emphysema do not receive enough oxygen and hardly eliminate carbon dioxide. __Lung cancer__ - Lung cancer takes away spae in the lungs that are used for gas exchange. __Atherosclerosis__ - Some of chemicals get into the blood and are absorbed by the blood vessels. This irritation build up of fatty material on the blood vessel walls that causes atherosclerosis. It can lead to heart attacks. In passive smoking, people involuntarily inhale the smoke from other people's cigarettes, cigars, or pipes. This smoke contains same chemicals as smokers inhale. About 300,000 kids in United States have problem of bronchitis or other parts of the respiratory system.