Gas Exchange and Transport

These flashcards cover key concepts regarding gas exchange, transport, and the respiratory system to aid in exam preparation.

What drives the diffusion of gases in the respiratory system?

Gases diffuse down their concentration gradients.

What is the typical atmospheric pressure of dry air in mm Hg?

760 mm Hg.

What is the PO2 in the alveoli?

100 mm Hg.

What is the primary factor affecting gas exchange in the lungs?

Concentration gradient.

What condition causes inspired air to have abnormally low oxygen content?

Altitude.

What is hypoxic hypoxia?

Low arterial PO2.

What does the term 'anemic hypoxia' refer to?

Decreased total amount of O2 bound to hemoglobin.

What causes ischemic hypoxia?

Reduced blood flow.

How does emphysema affect respiration?

Destroys alveoli, reducing surface area for gas exchange.

What affects the diffusion distance in gas exchange?

Pathological changes like pulmonary edema increase diffusion distance.

What percentage of carbon dioxide is converted to bicarbonate ions in the blood?

70%.

What is the primary function of hemoglobin in gas transport?

To bind oxygen and transport it in the blood.

What happens to carbon dioxide during gas exchange in alveoli?

It diffuses out of the blood into the alveoli.

What do central chemoreceptors respond to?

Changes in CO2 levels in the cerebrospinal fluid.

What is the role of glomus cells in the carotid body?

They release neurotransmitters when PO2 decreases.

What happens during bronchoconstriction?

Irritant receptors send signals causing airway constriction.