Learn RESPIRATION IN HUMAN With Me

HUMAN RESPIRATORY SYSTEM

Refer (i) http://www.tutorvista.com/content/science/science-ii/respiration/gaseous-exchange.php and (ii) http://www.cartage.org.lb/en/themes/Sciences/LifeScience/GeneralBiology/Physiology/RespiratorySystem/HumanRespiratory/HumanRespiratory.htmww.cartage.org.lb/.../HumanRespiratory.htm

BREATHING AND RESPIRATION IN HUMAN

Breathing occurs to provide oxygen to the alveoli and remove carbon dioxide and water from the body. Don't get confused with the term 'external respiration'.. refer gaseous exchange below.

The purpose of respiration is to provide oxygen to cells for the process of cellular respiration. Cellular respiration occurs in the mitochondria of cells and produces ATP energy for cellular processes. During cellular respiration, glucose and oxygen (nutrients) are converted to carbon dioxide and water (wastes). Respiration also removes these waste products with the help of the circulatory system. As before, don't get confused with the term 'internal respiration'.. just refer gaseous exchange below.

BREATHING MECHANISM

• Inhalation = Breathing in air
• Exhalation = Breathing out air

Refer images of 'breathing in and breathing out' at www.singintune.org/voice-production.html.

Refer explanations on breathing mechanism at http://www.geocities.com/hkbiology/gaseousexchange.htm.

The diaphragm looks like an overturned bowl, whose lip is at the base of the rib cage. Air flows into the lungs when the diaphragm contracts downward, giving the lungs room to expand downwards. The intercostal muscles of the ribs expand the rib cage outward, creating a partial vacuum. The external intercostal muscles contract and the internal intercostal muscles relax. This causes air to flow into the lungs where the air pressure is low, allowing equilibrium to be achieved. Breathing is not a matter of "sucking" in air. The rib cage expands first, causing the air to flow into the lungs.

Try this task..

INHALATION:

External intercostal muscles ............... >>Internal intercostal muscles .............. >>Rib cage moves upwards and ............. >>Diaphragm ............. and flattens. >>Volume of thoracic cavity .............. >>Air pressure in lungs ............. >>........... from outside enters the lungs

EXHALATION...?

Just like the 'inhalation'.. but the opposite.

GASEOUS EXCHANGE

• External respiration = The gas exchange between the alveoli and blood capillaries of the lungs
• Internal respiration = The gas exchange between the blood capillaries of the body and the body tissues. (If you learn more, this transport in not directly from the blood capillaries to the body tissues.. but via the interstitial fluid.. the fluid that bathes the body tissues)

Refer image at designanduniverse.com/articles/blood.php.

Refer (i) http://www.tutorvista.com/content/science/science-ii/respiration/gaseous-exchange.php and (ii) http://www.personal.psu.edu/dum153/blogs/writing/assignment-4/assignment-4.html for information on gaseous exchange in the lungs and in the body tissues.

Tips..

(i) The partial pressure of gas is equivalent to the concentration of the gas. (The higher the gas concentration, the higher the gas partial pressure).

(ii) Gas diffuses from a region of higher partial pressure (higher concentration) to a region of lower partial pressure (lower concentration).. by simple diffusion.

Describe these..

THE GASEOUS EXCHANGE IN THE LUNGS:

(i) The diffusion of oxygen from the air in an alveolus into the blood capillary. .....?
(ii) The diffusion of carbon dioxide from the blood capillary into an alveolus. .....?

THE GASEOUS EXCHANGE IN THE BODY TISSUES:

(i) The diffusion of oxygen from the blood capillary into a body cell. .....?
(ii) The diffusion of carbon dioxide from a body cell into the blood capillary. .....?

THE TRANSPORT OF RESPIRATORY GASES

Blood transports oxygen, carbon dioxide, and water between the lungs and body cells.

Refer www.coolschool.ca/lor/BI12/unit11/U11L05.htm.

Fill in the blank spaces..

THE TRANSPORT OF OXYGEN IN THE BLOOD:

1. Oxygen is carried by ................. molecules inside the ...............
Reaction in the red blood cell (Lungs): Hb (............) + O2 (...........) ->> HbO2 (............)

2. Upon reaching the body cells, .............. dissociates to form ............. and ...........
Reaction in the red blood cell (Body cells): HbO2 (..............) ->> Hb (...........) + O2 (........)

3. Blood high in oxygen gas releases oxygen gas into the body cells by ...................

THE TRANSPORT OF CARBON DIOXIDE IN THE BLOOD:

1. Carbon dioxide is transported mainly in blood plasma in the form of bicarbonate ion (70%).

Reaction in the blood (Body cells): CO2 (.............) + H2O (.........) ->> H2CO3 (..............) ->> H+ (..............) + HCO3- (.............) (Enzyme used .....................).

Water and carbon dioxide diffuse into the blood where they form carbonic acid. In the blood, carbonic acid is converted into bicarbonate ions and hydrogen ions by the enzyme carbonic anhydrase.

Reaction in the blood (Lungs): H+ (.............) + HCO3- (..............) ->> H2CO3 (..............) ->> CO2 (.............) + H2O (...........)

2. A small amount (23%) of the carbon dioxide combines with hemoglobin to form ............. in the red blood cells and is returned to the lungs in this form.

3. About 7% of the carbon dioxide is transported as dissolved carbon dioxide in the ............

4. Blood high in carbon dioxide gas releases carbon dioxide gas into the lungs by ...............

THE REGULATORY MECHANISM OF OXYGEN AND CARBON DIOXIDE CONTENT IN THE BODY

Search information at (i) www.emptynosesyndrome.org/respir8.html, and (ii) www.anmolarora.com/?p=216.

.....oooOOOooo.....