Respiratory System; Breathing and Respiraion

Edited by Jamie (ScienceAid Editor), Taylor (ScienceAid Editor)

Breathing

a cross section of the pleural cavity

This area is covered in a pleural membrane, forming the airtight pleural cavity, which allows breathing to take place. Air is drawn in and out of the lungs by changes in pressure and volume.

  1. 1
    Inhale'.
    Intercostal muscles contract, moving chest up and out; the diaphragm contracts and flattens. These increase the volume, so decrease the pressure, thus drawing air into the lungs.
    Was this step helpful? Yes | No | I need help

  2. 2
    Exhale.
    Intercostal muscles relax, chest moves down and in. The diaphragm relaxes, and domes upwards. Volume decreases, pressure increases and air is forced out of the lungs.
    Was this step helpful? Yes | No | I need help

Here is the structure of the lungs and an alveolus:

cross section of lung and diagram of an alveolus

Air goes into the lungs via the trachea, through the bronchi, bronchioles and then into the alveoli, where CO2 diffuses out of the blood, into the alveoli and is exhaled. And O2 diffuses into the blood stream and is transported around the body see circulation

Was this helpful? Yes | No | I need help

Respiration

Please see the main page respiration in Biochemistry.

Controlling Breathing

It is vital that we can control the rate of breathing to maintain a constant carbon dioxide and oxygen level in the body. This is done by three different processes which are coordinated by the medulla in the brain.

Was this helpful? Yes | No | I need help

  1. 1
    Stretch Receptors.
    In the lungs are stretch receptors that recognize how inflated the lungs are. When they reach a certain point, they are sent a message to deflate.
    Was this step helpful? Yes | No | I need help

  2. 2
    Chemoreceptors.
    In the aorta, are chemoreceptor cells. These can detect the concentration of carbon dioxide in the blood. If it gets too high, they will send a message to increase the rate of breathing.
    Was this step helpful? Yes | No | I need help

  3. 3
    Medulla And finally there is the medulla itself, which also responds to the levels of carbon dioxide in the blood.
    Was this step helpful? Yes | No | I need help

Comments

ScienceAid welcomes all comments. If you do not want to be anonymous, register or log in. It is free.




Jamie
Featured Author
166 Articles Started
1,271 Article Edits
43,065 Points
Jamie is a featured author with ScienceAid. Jamie has achieved the level of "Captain" with 43,065 points. Jamie has started 166 articles (including this one) and has also made 1,271 article edits. 43,400 people have read Jamie's article contributions.
Jamie's Message Board
Jamie: Hi, my name is Jamie.
Jamie: Can I help you with your problem about "Respiratory System; Breathing and Respiraion"?
 

Article Info

Categories : Humans

Recent edits by: Jamie (ScienceAid Editor)

Share this Article:

Thanks to all authors for creating a page that has been read 5 times.

Do you have a question not answered in this article?
Click here to ask one of the writers of this article
x

Thank Our Volunteer Authors.

Would you like to give back to the community by fixing a spelling mistake? Yes | No