RGI 1 Notes

This set of flashcards covers key concepts, functions, and regulations of the respiratory system as discussed in the lecture.

What is the primary function of the respiratory system?

To supply oxygen to the body and to remove carbon dioxide from the body.

What are the three distinct stages of gas exchange?

1. External respiration, 2. Gas transport, 3. Internal respiration.

Define aerobic respiration.

Aerobic respiration is a highly effective process for producing ATP from glucose but requires a steady supply of O2.

What is the role of surfactant in the alveoli?

Surfactant reduces surface tension and prevents alveoli from collapsing.

What happens to premature babies with insufficient surfactant?

They may experience respiratory distress syndrome, making lung expansion difficult.

What does the thoracic cavity contain?

The thoracic cavity contains the lungs, heart, and major blood vessels.

How does air flow during inhalation?

Air flows in when the intrapulmonary pressure falls below atmospheric pressure.

What is the role of the diaphragm in inhalation?

The diaphragm contracts, flattening and increasing the volume of the thoracic cavity.

What is the difference between intrapulmonary and intrapleural pressure?

Intrapulmonary pressure equals atmospheric pressure; intrapleural pressure is always negative.

What is the purpose of the Hering-Breuer reflex?

To prevent over-inflation of the lungs.

What is the structure that closes off the larynx during swallowing?

The epiglottis.

What type of infections are the most common respiratory tract infections?

Common colds, usually viral.

What is the conducting passage system of the respiratory tract?

Includes nostrils, nasal cavities, pharynx, larynx, trachea, bronchi, and bronchioles.

What separates the alveolar air from the blood stream?

Two thin cell layers: the epithelium of the alveolar wall and the endothelium of the capillary wall.

What occurs during exhalation?

The diaphragm and intercostal muscles relax, reducing lung volume and forcing air out.

What muscles are involved in forced exhalation?

Abdominal wall muscles and internal intercostal muscles.

What indicates the metabolic activity levels of an organism?

Oxygen requirement levels correspond to metabolic activity.

What is the clinical significance of a pneumothorax?

It results from loss of negative intrapleural pressure, causing lung collapse.

How are the respiratory center neurons organized?

Grouped in three areas: the dorsal respiratory group, ventral respiratory group, and pontine respiratory group.

What role do chemoreceptors play in respiration?

They sense the concentrations of CO2, H+, and O2, regulating respiratory rate and depth.

What happens during gas transport in the blood?

Oxygen and carbon dioxide are transported through the bloodstream.

What anatomical feature allows for gas exchange in the alveoli?

The extremely thin epithelial layer lining each alveolus.

How many breaths per minute characterize quiet breathing?

Approximately 12 breaths per minute.

What is the primary difference between active and passive exhalation?

Active exhalation requires muscle contraction, while passive exhalation is largely due to elastic recoil.

Which type of cell produces surfactant in the alveoli?

Type II pneumocyte.

What abnormalities can arise from pressure changes in the thoracic cavity?

Changes in pressure can lead to respiratory complications such as pneumothorax.

What is the significance of the pleural cavity?

The pleural cavity provides lubrication and a negative pressure environment for lung inflation.

What conditions must be met for effective gas exchange in the alveoli?

A large surface area, thin membranes, and adequate surfactant levels.

What factors can increase respiratory rate according to the chemical regulation of respiration?

Increased levels of CO2 and H+ in the blood.

How do intercostal muscles assist with inhalation?

They contract to raise the rib cage, aiding in the expansion of the thoracic cavity.

What does the term 'homeotherm' refer to?

Warm-blooded animals that have high oxygen requirements.

What is the function of cilia in the respiratory tract?

To push mucus upwards and protect the airways.

How does the body respond to low oxygen levels?

Peripheral chemoreceptors trigger an increase in respiratory rate.

What defines internal respiration?

The process of oxygen uptake and carbon dioxide production within cells.

What is the primary function of the vocal cords located in the larynx?

To facilitate sound production when air passes through.

What is the importance of alveolar surface area?

A greater surface area allows for more effective gas exchange.

How does the thoracic cage assist respiration?

It provides structure and support to the lungs and aids in changes of pressure.

What is the physiological consequence of a collapsed lung?

A pneumothorax can lead to difficulties in breathing and reduced oxygenation.

What happens to the lungs during an active breathing process?

The volume of the thoracic cavity increases, leading to a decrease in lung pressure.

How many lobes does the right lung have compared to the left lung?

The right lung has 3 lobes, while the left lung has 2 lobes.

Why is intrapleural pressure important for lung function?

It prevents lung collapse by creating a negative pressure environment.

What is the main cause of respiratory distress syndrome in neonates?

Insufficient surfactant production due to immature lung development.

What are the effects of the pontine respiratory group?

It controls the length of each breath by sending inhibitory signals to the inspiratory center.

What is the main focus of Hering-Breuer reflex?

It helps regulate the depth of breathing by preventing over-inflation.