Week 2 - Respiratory Sytem Flashcards
What is the function of the nose?
The nostrils provide entrance to the nasal cavity; internal hairs begin to filter incoming air
Location: Part of face centred above the mouth, in and below spaces between eyes
What is the function of the nasal cavity?
Conducts air to the pharynx: mucous lining filters warms and moistens incoming air.
Location: Hollow space behind nose
What is the function of the Paranasal Sinuses?
Reduce the weight of the skull; serve as resonant chambers
Location: Hollow spaces in certain skull bones
What is the function of the Pharynx?
The passageway for air moving from the nasal cavity to the Larynx and for food moving from oral cavity to esophagus.
Location: Space behind the oral cavity, the nasal cavity, and epiglottis.
What is the function of the Larynx?
The passageway for air; prevents foreign objects from entering the trachea; houses the vocal cords.
Location: Enlargement at top of Trachea
What is the function of the trachea?
The passageway for air; mucous lining, continues to filter particles from incoming air
Location: Flexible tube that connects the Larynx with bronchial tree
Description: Flexible cylindrical tube (windpipe)
What is the function of the Bronchial Tree?
Conducts air from Trachea to Alveoli; mucous lining continues to filter particles from incoming air.
Location: Branched tubes that lead from Trachea to Alveoli
What is the function of the Lungs?
Contain air passages, alveoli, blood vessels, connective tissues, lymphatic vessels, and nerves.
Location: Soft, cone-shaped organs that occupy a large portion of the thoracic cavity.
What does the upper respiratory tract contain?
Includes the nose, nasal cavity, paranasal sinuses, pharynx and larynx.
What does the lower respiratory tract contain?
Includes the trachea, bronchial tree, and lungs
What is the nasal septum?
The Midline wall of bone and cartilage that separates the nasal cavity into right and left parts.
What are the nasal conchae and its function?
Any of the shelf-like bones or bony processes extending medially from the wall of the nasal cavity; also called a turbinate bone.
Supports the mucous membrane that lines the nasal cavity.
Helps increase the mucous membrane’s surface area.
What does the mucous membrane in the nasal cavity contain?
pseudostratified ciliated epithelium that is rich in mucus-secreting goblet cells.
Also includes an extensive network of blood vessels.
What are the functions of the mucous membrane that lines the nasal cavity?
The mucous membrane is pseudostratified ciliated epithelium. There are many blood vessels in this area. The epithelial layer and blood warm, moisten, and filter incoming air. Mucus traps dust and pathogens, and cilia move the mucus to the Pharynx to be swallowed. Trapped microorganisms are destroyed in the stomach.
What is the Larynx composed of?
A framework of muscles and cartilages bound by elastic tissue. The largest cartilage is the Thyroid.
What is inside the Larynx?
Two pairs of horizontal vocal folds, composed of muscle tissue and connective tissue with a covering of mucous membranes.
Upper folds are called false vocal cords because they do not produce sound.
The muscle fibers within these folds help close the airway during swallowing.
What do the lower folds of the Larynx do?
They are the true vocal cords. They are made up of muscle fibers and strong, elastic connective tissue.
What lines the inner trachea walls?
A ciliated mucous membrane with many goblet cells
What is internal respiration?
Gas exchange between blood and tissue
What is ventilation?
Movement of air into and out of the lungs
What is cellular respiration?
The use of Oxygen for metabolic reactions within cells
What are the correct steps of inspiration, starting from the nose?
- Nasal Cavity
- Nasopharynx
- Oropharynx
- Laryngopharynx
- Larynx
What are the bony processes that curl out from the lateral walls of the nasal cavities, serving to stir up the air as it is inhaled?
Conchae
Describe what the Bronchial Tree consists of…
Consists of branched airways leading from the Trachea to the microscopic air sacs in the lungs.
1. Its branches begin with the right and left main (primary) bronchi.
2. Each bronchus enters its respective lung.
3. Each main bronchus divides into LOBAR (secondary) Bronchi and then into increasingly finer tubes.
4.
Describe what the Bronchial Tree consists of…
Consists of branched airways leading from the Trachea to the microscopic air sacs in the lungs.
- Its branches begin with the right and left main (primary) bronchi.
- Each bronchus enters its respective lung.
- Each main bronchus divides into LOBAR (secondary) Bronchi and then into increasingly finer tubes.
- Among these smaller tubes are bronchioles that continue to branch, giving rise to terminal bronchioles,, respiratory bronchioles and very thin tubes called Alveolar Ducts.
- The Alveolar Ducts lead to Alveolar sacs.
- Alveolar sacs are composed of microscopic air sacs called Alveoli, which lie within capillary networks.
- The Alveoli are sites of gas exchange between the inhaled air and bloodstream.
What do the mucous membranes of the Bronchial tree do?
They continue to filter incoming air, and the many branches of the tree distribute the air to alveoli throughout the lungs.
What does the Alveoli do?
Provide a large surface area of thin squamous epithelial cells through which gases are easily exchanged.
Oxygen diffuses from the alveoli into the blood in nearby capillaries, and co2 diffuses from the blood into the alveoli.
What is the function of the cartilaginous rings in the tracheal wall?
The rings of the Trachea prevent the collapse of the trachea and blockage of the airway leading to the lungs.
What is the difference between the right and left lung?
- The right lung is larger
- ## The right lung is divided into 3 lobes and the left is divided into 2 lobes
What is the Visceral Pleura?
Serous membrane that covers the surface of each lung.
What is the Parietal Pleura?
Serous membrane that covers the inner surface of the thoracic cavity wall.
It borders part of the mediastinum and lines the inner wall of the thoracic cavity and the superior surface of the diaphragm.
What is the Pleural cavity?
Potential space between the visceral and parietal pleural membranes.
What happens if there is a puncture in the thoracic wall of the lungs?
It will admit atmospheric air into the pleural cavity and creates a real space between the membranes.
This condition, called PNEUMOTHORAX, may collapse the lung on the affected side because of the lung’s elasticity.
What is a collapsed lung called?
Atelectasis
What is atmospheric pressure?
Pressure exerted by the weight of air surrounding the earth, equivalent at sea level to the weight of a column of Mercury 760 milliliters high.
Describe the events of Inspiration…
- Nerve impulses from the phrenic nerves stimulate the diaphragm to contract downward.
- This increases the volume inside the thoracic cavity and decreases the pressure of the gases inside the lung.
- When the pressure drops to a level slightly below atmospheric pressure, air rushes into the air passages and reaches the alveoli.
- Once in the Alveoli, oxygen diffuses into the alveolar capillaries.
How does the expansion of the chest wall expand the lungs during inspiration?
- The diaphragm contracts downwards, and the external intercostal muscles cause the wall of the thoracic cavity to move outward and upward.
- The parietal pleura moves along with the thoracic wall as it expands
- Since the parietal pleura is held against the visceral pleura by the serous fluid between them, the layers of the pleural membrane move together.
- The visceral pleura is attached to the outer surface of the lungs.
- Therefore, when the thoracic cavity expands, and both layers of the pleura expand with it, the lungs expand too.
What is surface tension?
Force due to the attraction of water molecules that makes it difficult to inflate the alveoli of the lungs.
What forces cause normal expiration?
- Forces involved in normal expiration are derived from elastic recoil of the tissues that stretched during inspiration and from surface tension in the alveoli.
- During expiration, when the diaphragm and external intercostal muscles are no longer being stimulated to contract, they snap back to their relaxed positions.
- The stretched elastic tissues of the lungs also return to their original positions.
- As elastic recoils, surface tension increases in the alveoli, decreasing their diameter.
- These events increase the pressure inside the alveoli to a level slightly higher than that of atmospheric pressure.
- Air now rushes passively out of the lungs and air passages.
What is Spirometry?
A procedure that measures air volumes.
What is tidal volume?
The volume of air entering and leaving the lungs in a respiratory cycle.
What is the normal amount of air that enters the lungs in a respiratory cycle?
500 mL.