Where does gas exchange occur in the lungs? What role do the diaphragm and rib muscle play in inhalation and exhalation?

8. Where does gas exchange occur in the lungs?

9. What role do the diaphragm and rib muscle play in inhalation and exhalation?

Expert Solution

8) Alveoli are the primary sites of exchange of gases in the lungs. Exchange of gases mainly occur in between the alveolar cavity of lungs and blood capillaries.

The diffusion membrane is made up of three layers namely, the thin squamous epithelium of the alveolar wall, the endothelium of the alveolar capillaries and basement material in between them. As it is very thin border, it is favourable for diffusion of gases.

9) Expansion of chest during inspiration occurs as a results of muscular activity, partly voluntary and partly involuntary.

The main muscles used in normal breathing are the intercostal muscles of ribs and the diaphragm.

The external intercostal muscles.

These extend downward and forwards from lower border of the rib above to the upper border of the ribs below. They are involved in inspiration.

The internal intercostal muscles :

These extend downwards and backwards from lower border of the rib above to the upper border of the ribs below, crossing the external intercostal muscle fibers at right angles. The internal intercostals are used when exhalation becomes active as in exercise.

The first rib is fixed. Therefore when the external intercostal muscles contract they pull all other ribs towards the first rib. Because of shape and sizes of the ribs they move outwards when pulled upwards enlarging the thoracic cavity.

Diaphragm :

The diaphragm is a come shaped muscular structure separating the thoracic and abdominal cavities. It forms the floor of the thoracic cavity and roof of the abdominal cavity and consists of a central tendon from which muscle fibers radiate to be attached to lower ribs and sternam and to vertibral column by two crura.

When the muscle of the diaphragm is relaxed the central tendon at the level of eight th (8 th) thoracic vertebra. When it contacts it's muscle fibers shorten and central tendon is pulled downwards to th level of 9 th thoracic vertebra lengthening the thoracic cavity. This decrease pressure in thoracic cavity and increase it in abdominal pelvic cavities.

gladiator answered 2 years ago

the effects of the inhalation of smoke and E-cigarette vapor on gas exchange in the lungs;...

the effects of the inhalation of smoke and E-cigarette vapor on gas exchange in the lungs; specific diseases associated with smoking, both pulmonary and cardiovascular; and lastly, based on what you know about E-cigarettes from the reading and your own research, defend or oppose the regulation of vaping products as traditional cigarettes.

What role does calcium play in this regulation, and where is it stored in a muscle fiber?

What role does the motor neuron play in stimulation of muscle contraction? What role does the...

What role does the motor neuron play in stimulation of muscle contraction? What role does the sarcoplasmic reticulum play in muscle contraction? What is the difference between aerobic and anerobic muscle contraction? What happens in a reflex response?

What role does the destruction of neurotransmitters play in the functioning of neurons and muscle cells?

What does the prostate do and where is it located? What role does FSH and LH play in the male productive system?

1. What role does a play in the actual contraction of a muscle ber (skeletal and cardiac)?

1. What role does a play in the actual contraction of a muscle ber (skeletal and cardiac)? 2. How do cardiac muscle and skeletal muscle differ in the role of Cain stimulation of muscle fibers? How does this difference affect the changes in membrane potential in cardiac muscle? 3. Based on the information in questions 1 and 2 explain why cardiac muscle does not demonstrate tetanic muscle contractions

what role does a CEO play in an organization's cultures? what role do other leaders/managers play?

What role does water vapor pressure play in molar gas experiements?

What role do social capital and influence play in online communities? 2. Where does social media...

What role do social capital and influence play in online communities? 2. Where does social media marketing planning fit into an organization’s overall planning framework? 3. What are the phases of social media marketing maturity? How does social media marketing change for companies as they shift from the trial phase to the transition phase and eventually move into the strategic phase? 4. What are the steps in social media marketing strategic planning? 5. What forms of paid media can be...

Does the nervous system play a role in muscle force production? If yes, Explain

Question