RESPIRATORY SYSTEM

Your respiratory system brings O2 into your body and removes CO2 and H2O. This is very important, because a person could live for days without food and water but only a matter of minutes without breathing.

BREATH IN, BREATH OUT

The purpose of breathing is to bring O2 to the cells of the body and remove CO2.

INHALING & EXHALING

Air can enter the body through the mouth and/or the nose. Although the nose is much healthier to breath through. Your nose warms, mucous moistens the air and cleans the air as it passes. (cilia & mucous) Thus, the nose acts like an air filter. Your lungs are not muscles (they are tissues), thus your respiratory system needs help from the skeletal and muscular systems. Your muscle called the diaphragm enables you to breath. When you inhale, your diaphragm contracts and your lungs expand as air enters your body. (ribs move outward) When you exhale, your diaphragm relaxes and your lungs contract as air leaves your body.

TAKING A BREATH

When you inhale air enters through your nose or mouth. The place where your nasal passages and mouth meet is called the pharynx. Then the air enters your windpipe or trachea which leads to two tubes (the bronchi) which carry the air to each lung. Rings of cartilage are responsible for holding your trachea open. The epiglottis is the structure that prevents food and liquid from entering your lungs.

IN THE LUNGS

As air enters the lungs, through the bronchi, passageways become smaller and smaller branching into bronchioles. At the ends of these branches form small grape-like air sacs called alveoli. It is here were gas exchange takes place.

GAS EXCHANGE

Gas exchange takes place through capillary walls surrounding the air sacs of the alveoli. Here oxygen enters the bloodstream while carbon dioxide leaves. The air you breathe in is really a mixture of gases. Oxygen accounts for 19-21%, while carbon dioxide is only .04%. Your blood can only carry oxygen and carbon dioxide in large quantities.

SPEECH

The larynx is your voice box which houses your vocal cords. You produce sounds by passing air through the larynx that causes the vocal cords to vibrate.

CELLULAR RESPIRATION

Cellular respiration is the process by which a cell releases energy from food. This occurs in the mitochondria. The two types of cellular respiration are aerobic and anaerobic respiration.

Aerobic respiration is with oxygen. It is respiration requiring the help of oxygen to foods such as sugar (glucose) and changing it into energy and carbon dioxide and water (CO2 and H2O).

The overall reaction for aerobic respiration is:

C6H12O6 + 6O2 à 6CO2 + 6H2O + ATP

(glucose + oxygen à carbon dioxide + water + energy)

**the energy released is stored as ATP, this can be used by the cell to do work when it is needed.

Anaerobic respiration is without oxygen. It is when the breakdown occurs without oxygen (O2) to produce energy but it releases either lactic acid or alcohol.

The overall reaction for anaerobic respiration is:

C6H12O6 à CO2 + alcohol + ATP

(glucose à carbon dioxide + alcohol + ATP)

or

C6H12O6 à CO2 + lactic acid + ATP

(glucose à carbon dioxide + lactic acid + ATP)

SUMMARY

Ø  Mechanical respiration is the process in which the body obtains oxygen and gets rid of carbon dioxide.

Ø  Cellular respiration is the process by which cells release energy from food.

Ø  In aerobic respiration, glucose is broken down with the help of carbon dioxide (O2).

Ø  In anaerobic respiration, glucose is broken down without the help of oxygen.

Ø  The energy that is produced, stored, and used is ATP.

RESPIRATORY SYSTEM

RELATIONSHIPS between…

SKELETAL
SYSTEM / MUSCULAR SYSTEM / CIRCULATORY SYSTEM
Ø  The ribs protect
the lungs. / Ø  The diaphragm is
an involuntary and voluntary muscle which helps you breathe. / Ø  The blood carries
oxygen and carbon dioxide to the lungs. The lungs filter the blood and this oxygenated blood returns to the heart.
Ø  Protects the lungs
& other parts from damage. / Ø  Protects / Ø  Transports gases
between the cells of the body & lungs.
Ø  Ribs expand
when you breathe in. / Ø  Brings O2 to all
the cells of the body.
Ø  Removes CO2 &
water from the cells.
Ø  Transports gases
Between the cells of body & lungs.
Ø  Brings O2 to all
the cells of the body.
Ø  Removes CO2
& H2O from the cells.

The path of oxygen through the respiratory system is:

In through the nose (nasal cavity)/mouth → pharynx → epiglottis → larynx → trachea → bronchi → bronchioles → alveoli → blood → alveoli → bronchioles → bronchi → trachea → larynx → epiglottis → pharynx → nose (nasal cavity)/mouth