Lab 7: Respiratory Air Flow and Volume

4 Steps of Respiration

1. Pulmonary Ventilation

2. External Respiration

3. Transport of respiratory gases

4. Internal Expiration

Spirometry is what?

A technique for recording respiratory variables.

Pulmonary Ventilation

is the movement of air into (inspiration) and out of (expiration) lungs.

What is the purpose of ventilation?

Works to ensure gases in the lung are constantly refreshed with infusions of new air and effusions of old air.

Explain gas exchange during external respiration

CO2 diffuses to the lungs from the blood and oxygen diffuses to the blood from the lungs

Transport of gases is accomplished using what?

Blood of the cardiovascular system.

Explain gas exchange during transport of respiratory gases

CO2 is transported from the cells of body tissues to the lungs & O2 is transported from the lungs to the cells of body tissues.

Hypoxia

inadequate oxygen delivery to the body tissues & is classified based on the cause.

Anemic hypoxia

poor oxygen delivery due to the erythrocytes that contain too little or abnormal Hb or from too few erythrocytes.

Ischemic hypoxia

results from blocked or impaired blood circulation.

Histotoxic hypoxia

results when adequate oxygen is delivered but the body cells are unable to use it (such as the case of metabolic poisonings - cyanide)

Hypoxemic hypoxia

when the partial pressure of dissolved oxygen in the arteriole blood is low.

What are the causes of hypoxemic hypoxia

Commonly caused by disordered ventilation-perfusion coupling, pathological pulmonary ventilation impairment, and breathing air deficient in O2

Give an example of hypoxemic hypoxia

Carbon monoxide poisoning (caused by breathing smoke from air or inhaling fumes of combustion).

Explain the relationship between CO, O2, and Hb.

CO has an higher affinity for Hb than O2 does and thus outcompetes oxygen for hemoglobin binding sites.

Does carbon monoxide cause cyanosis? What kind of therapy is recommended?

No; it causes confusion & throbbing headaches.

Hyperbaric therapy is indicated if available.

What controls respiration?

The reticular formation of the pons and medulla oblongata.

Who sets the rhythm?

The Medullary respiratory centers of the medulla oblongata.

1. Ventral respiratory group

2. Dorsal respiratory group

The ventral respiratory group is said to be what?

A rhythm generating and integration center for breathing.

Talk about inspiration in relation to the ventral respiratory group.

To initiate inspiration, it sends APs down to the phrenic nerve (to the diaphragm) and intercostal nerves (to external intercostal muscles)

Talk about expiration in relation to the ventral respiratory group.

The expiratory neurons of this group fire which stops the output from the inspiratory neurons of this group to allow for passive expiration.

It is hypothesized that neurons in medulla oblongata, acting within and with the centers cycle through what?

-

T/F The trachea is an elastic structure.

True

What is the functions of the cartilage rings (according to the lab manual)?

1. Allow the esophagus behind to expand during swallowing

2. Hold it open so that air can continuously move

Name the type of epithelia found in the mucosa

Pseudostratified ciliated columnar epithelia