Respiratory System Flashcards
What are the 3 functions of the respiratory system?
1) Provides the body with O2.
2) Excretory organ - CO2, heat, water, alcohol and ketones
3) Maintains the pH of body fluids.
Describe the gross anatomy of the right lung
It is wider and shorter than the left lung (because it sits on top of the liver)
Describe the gross anatomy of the left lung
It is taller and narrower than the right lung (because more of the heart sits behind the left lung)
What are the 3 different lobes of the right lung?
1) Superior
2) Middle
3) Inferior
What are the different fissures that separate the lobes of the right lung?
Horizontal - separates the superior and the middle
Oblique - separates the inferior from the other 2 lobes
What is the fissure called that separates the lobes of the left lung?
Oblique
How to describe the membranes surrounding the lungs?
Double plural membrane
What are the names of the plural membranes surrounding the lungs and what is contained between them?
Visceral pleura (surrounding lungs) and parietal pleura. In-between the 2 layers = plural fluid
3 important roles of the double plural membranes surrounding the lungs?
1) Resist friction between the lungs and the surrounding structures when breathing in and out
2) Creates a pressure gradient which assists ventilation.
3) Isolates the 2 lungs - so infection in one doesn’t cause infection in the other
What are the 3 components of the upper respiratory tract?
1) Nasal cavity
2) Pharynx
3) Larynx
What are the 3 components of the lower respiratory tract?
1) Trachea
2) Bronchus
3) Right and Left Lung
What is meant by the conducting zone of the respiratory tract and what are its components?
The parts of the LOWER respiratory tract that are responsible for getting air to the respiratory zones
1) Trachea
2) Left and right primary bronchus, secondary bronchus, tertiary bronchus, bronchioles, terminal bronchioles
What is meant by the respiratory zone of the respiratory tract and what are its components?
The parts of the LOWER respiratory tract that are responsible for gas exchange.
1) Respiratory bronchioles
2) Alveolar sacs
What are the 3 functions of the nasal cavity?
1) Warm and cleanse the air (nose hairs will filter and add moisture to the air)
2) To detect odours
3) Modifies the sound of our voice.
What are the names of the 2 mucus membranes in the nasal cavity?
1) Olfactory mucosa
2) Respiratory mucosa
What 3 things are beneath the respiratory mucosa?
1) Goblet cells
2) Mucus glands
3) Cirus glands (secrete a water fluid that contains lysosomes)
What are conchae and what is the importance of them?
(superior, middle and inferior conchae)
Conchae are folds of tissue in the nasal cavity.
1) Allow for the turbulent flow of air
2) The blood flowing through the conchae allow for the air to warm up
3) The mucus membranes surrounding the conchae allow for the air to be humidified.
What are meati?
(superior, middle and inferior meati)
The channels inbetween the conchae.
What are the air sinuses and what is their function?
Air sinuses are holes in the skill and they secrete mucus.
Where is the pharynx located?
Continuous with the nasal cavity and extends down to the larynx
What is the role of the pharynx?
1) Passageway for air and food
2) Mucus that moves down the pharynx warms and humidifies the air
3) Modifies the sound of your voice.
What are the 3 sections of the pharynx and what does it convey?
1) Nasopharynx (air)
2) Oropharynx (food and air)
3) Laryngopharynx (food and air)
What does the larynx connect?
The larynx connects the laryngopharynx to the trachea.
What is the larynx made of and their importance?
Rings of cartilage, in order to maintain an open airway
What are the 3 components of the larynx?
1) Epiglottis
2) Thyroid cartlidage
3) Trachea
How does the larynx help us swallow and what is the importance of this?
1) The larynx pushes up
2) The epiglottis moves down to cover the larynx
This is so food enters the oesophagus and not the trachea
How does the larynx help the cough reflex?
1) The larynx pushes down and builds up pressure behind it.
2) Air moves into the pharynx
What is the larynx also described as and why?
‘Voice box’ - because different tensions the larynx creates modifies they way we speak
What is the trachea made of and their importance?
‘C- shaped cartilage’ - with smooth muscle in-front of the oesophagus, in order to expand to allow food to get through
How to describe the epithelial cells lining the trachea?
Pseudo-stratified columner epithelium
Where does the cilia transport the mucus in the upper respiratory tract and lower respiratory tract (and what is the importance of this)?
Upper respiratory tract - Down towards the pharynx
Lower respiratory tract - Up towards the pharynx
This is so the mucus can be swallowed and enter the oesophagus
What are the components of the bronchial tree?
1) Trachea
2) Left and Right Primary bronchus
3) Left (2) and Right (3) Secondary bronchus
4) Tertiary bronchus
5) Bronchioles
6) Terminal Bronchioles
7) Respiratory Bronchioles
How does the cartilage change as you go down the bronchial tree?
Rings of cartlidage, starts to become platelets at the secondary bronchus and at the bronchioles and further there is no cartlidge
What is the most sensitive part of the respiratory tract?
Carina (the end of the trachea, just before it splits into the right and left primary bronchus
How do the epithelial cells change as you move down the bronchial tree?
1) Trachea - pseudostratified columner cells
2) Primary Bronchus - pseudostratified columner cells
3) Secondary Bronchus - non- pseudostratified and pseudostratified columner cells
4) Tertiary Bronchus - simple columner cells
5) Bronchioles - simple columner
6) Terminal bronchiole - simple columner
7) Respiratory bronchiole - cuboidal
8) Alveoli - squamous
Where does gas exchange take place?
The capillary network surrounding the alveoli
Describe the blood flow to and from the capillary network surrounding the alveoli?
Pulmonary arteriole - brings deoxygenated blood from the heart to the lungs
Pulmonary venule - takes oxygenated blood from the lungs to the heart
What are the 2 types of alveolar cells and their function?
Type 1 - squamous epithelial cells (O2 diffuses through, basement membrane, capillary endothelium, erythrocytes)
Type 2 - septal cells (secretes serfactant which coats the inside of the alveoli and is important for the lungs to inflate)
Def. of pulmonary ventilation:
The exchange of air between the atmosphere and the alveoli in the lungs.
What is the difference between quiet ventilation and forced ventliation?
Quiet - at rest
Forced - when exercising
What are the 2 muscles that are involved in quiet ventilation?
1) External inter-coastal muscles
2) Diaphragm
What happens during quiet inspiration?
(active process)
1) External inter-coastal muscles contract and expand outwards - pushing the ribcage up and outwards
2) Diaphragm contacts and flattens out
3) The volume in the thoracic cavity increases and intra pulmonary pressure decreases lower than atmospheric pressure
4) Air is forced into the lungs (down the pressure gradient)
What happens during quiet expiration?
(passive process)
1) External inter-coastal muscles relax and pull inwards - pulling the ribcage in and downwards
2) Diaphragm relaxes and becomes domed shaped
3) The volume in the thoracic cavity decreases and the intrapulmonary pressure increases higher than atmospheric pressure.
4) Air is forced out of the lungs (down the pressure gradient) UNTIL INTRAPULMONARY PRESSURE = 0.
What muscles assist in forced ventilation?
Accessory muscles which assist the external intercoastal muscles
Which 4 muscles assist the external inter-coastal muscles in in forced inspiration?
(active process)
1) Scalenes (3 pairs of muscles in the neck, attached to the 1st and 2nd ribs)
2) Sternocleidomastoid (attaches to the sternum and the mastoid muscle in the neck)
3) Pectoralis minor
4) Pectoralis major - fan shaped muscles
What 4 muscles assist the external inter-costal muscles in forced expiration?
(active process)
1) Internal intercostal muscles (form a cross behind the external intercostal muscles)
2) Oblique muscles (attach the 8 lower ribs to the pelvic gurdle)
3) Rectus abdominis muscles (attach the xiphisternum to the pelvic gurdle)
4) Quadratus Luborum (connects the pelvic gurdle to the spine)
Atmospheric pressure
The pressure created by the air and gases surrounding the body