Enlaces intercambio de gases

http://www.youtube.com/watch?v=AyUtdqiOgCA

http://www.youtube.com/watch?v=AJpur6XUiq4

All cells need oxygen. It is the essential fuel which is necessary to our neighbor cells to stay alive and to carry out their various activities.

Bringing oxygen to the cells requires: the uptake of oxygen from the air in the lungs, its transportation in the blood, and its delivery to cells all over the body.

The first step is the taking up of oxygen by blood flowing through fine capillaries in the walls of the lungs’ air sacs or alveoli.

The oxygen molecules change from their state as a gas freely circulating in the air dissolving into a solution in the plasma within the capillaries of the alveoli. Once in the solution in the blood, 90% of this dissolved oxygen is taken up by passing red cells leaving just 2% remaining in the physical solution unattached.

Red cells are particularly well suited to transporting oxygen because they contain a special oxygen binding protein known as hemoglobin.

Each molecule of hemoglobin itself contains four molecules of heme, an iron containing pigment which binds oxygen loosely and reversibly.

Hemoglobin that is fully saturated with oxygen is bright red and is called oxyhemoglobin.

On the other hand, hemoglobin that is not saturated with oxygen is purplish bluey color and is called deoxyhemoglobin.

It is heme which makes it possible for the red cells to pick up oxygen dissolved in the blood, transport it combined with hemoglobin and release it back into the blood as oxygen in solution ready for delivery to the various cells in the body.

Hemoglobin gives up its oxygen as red cells travel through capillaries in tissues where there is a low content or partial pressure of oxygen. The partial pressure of oxygen represents the level of dissolved oxygen in plasma.

As oxygen is released and it then is carried in solution, the partial pressure in capillaries becomes greater than the partial pressure of oxygen in the surrounding tissues. This causes oxygen to move out of the capillaries into the tissues and to finally reach the cells.

Windpipe = trachea

voice box = larynx

rib cage = thoracic cavity

air sacs = alveoli

main branches of trachea = bronchi

secondary branches = bronchioles

throat = pharynx

network of capillaries

inspiration = inhalation

expiration = exhalation

Gaseous Exchange

All cells need oxygen. It is the essential fuel which is necessary to our neighbor cells to stay alive and to ______their various activities.

Bringing oxygen to the cells requires: the ______of oxygen from the air in the ______, its transportation in the blood, and its ______to cells all over the body.

The first step is the taking up of oxygen by blood ______through fine ______in the walls of the lungs’ air sacs or alveoli.

The oxygen molecules change from their ______as a gas freely ______in the air ______into a solution in the ______within the capillaries of the ______. Once in the solution in the blood, ______of this dissolved oxygen is taken up by passing ______leaving just 2% remaining in the physical solution unattached.

Red cells are particularly well suited to ______oxygen because they contain a special oxygen ______protein known as ______.

Each molecule of hemoglobin itself contains four molecules of heme, an iron containing ______which binds oxygen loosely and ______.

Hemoglobin that is ______saturated with oxygen is bright red and is called ______.

On the other hand, hemoglobin that is not ______with oxygen is purplish bluey color and is called deoxyhemoglobin.

It is heme which makes it possible for the red cells to ______oxygen ______in the blood, transport it ______with hemoglobin and ______it back into the blood as oxygen in solution ready for delivery to the various cells in the body.

Hemoglobin gives up its oxygen as red cells travel ______capillaries in ______where there is a low content or partial ______of oxygen. The partial ______of oxygen represents the level of dissolved oxygen in ______.

As oxygen is released and it then is carried in solution, the partial pressure in capillaries becomes greater than the partial pressure of oxygen in the ______tissues. This causes oxygen to ______of the capillaries into the tissues and to finally ______the cells.

Alveoli / binding / capillaries / carry out / circulating / combined / delivery / dissolved / dissolving / flowing / fully / hemoglobin / lungs / move out / oxyhemoglobin / pick up / pigment / plasma (2) / pressure (2) / reach / red cells / release / reversibly / saturated / state / surrounding / tissues / through / transporting / uptake / 90%