BODY SYSTEMS
RESPIRATORY
,Medic_Summaries (Body Systems)
Respiratory Strand
Respiratory system utilised for:
- Gas exchange
- Speech
- Smell
Functional divisions of the respiratory system:
- Conducting portion:
- From the nasal cavity to the terminal bronchi
- Transports air
- Conditions air (warm, moisten, filter)
- Has four paranasal sinuses (warm, moisten, filter)
- Sinus: space within skull
- Paranasal: next to the nasal cavity
- Respiratory portion:
- Thin, moist, delicate membrane (alveoli)
- Site of gaseous exchange
Conchae:
- Air passes into the nasal cavity over ridges called conchae
- These create turbulence and condition the air (warm, moisten, filter)
Problems:
- Pathogens thrive in this environment (pass in through sinuses and fester in mucus)
- Sinuses fill up from the bottom and therefore only empty when full
Frontal sinus: found in the frontal lobe
Ethmoidal cells: found in the bridge of the nose
Sphenoid sinus: found above the torus tubarius
Maxillary sinus: found above the maxilla (largest sinus)
Basic anatomy:
- Uvula hangs from roof of mouth (closes nasopharynx to stop food entering nasal cavity)
- Air passes down the pharynx to the oesophagus/trachea, passing the larynx (voice box)
- The trachea splits into two primary bronchi (left/right) before entering the lungs
- Mediastinum encloses the heart, major vessels, nerves, the trachea and the oesophagus
Lungs:
- Right lung:
- Trilobal (superior, middle and inferior lobes)
- Shorter, broader and larger
- An oblique fissure divides superior/inferior and middle/inferior lobes
- A horizontal fissure divides superior/middle lobes
- Left lung:
- Bilobal (superior and inferior lobes)
- Taller, narrower and smaller
- An oblique fissure divides superior/inferior lobes
2 Adapted from Lectures at the University of Leeds Medical School
, Medic_Summaries (Body Systems)
Medial view:
- Lung roots connect lungs to mediastinal structures
- Medial surface contains series of holes
- Most posterior is cartilaginous bronchi
Pulmonary arteries: take deoxygenated blood to the lungs
Pulmonary veins: take oxygenated blood away from the lungs
Conducting portion:
- Consists trachea and primary, secondary (lobar), tertiary (segmental) and terminal bronchi
- Where the trachea bifurcates is called the CARINA
- Within each lobe of a lung are a series of segments (each with separate arterial/air supply)
- If part of a lung gets damaged, the lung can still function (segmental damage)
Respiratory portion:
- Consists branches of terminal bronchioles to respiratory bronchiole/alveolar sacs
- Emphysema is an enlargement of the alveolar sacs, causing damage to the alveolar walls
- The hilum of the lung is the region through which structures comprising the lung root pass
Functional vs. anatomical:
- Functional:
- Conducting portion
- Respiratory portion
- Anatomical:
- Upper respiratory tract (URT) - nasal cavity to larynx/sinuses (common cold)
- Lower respiratory tract (LRT) - trachea to bronchi in lungs (pneumonia)
The thoratic cage:
- Functions:
- Protection:
- Forms a cage around vital organs (including upper abdominal organs)
- Respiration:
- Changes in thoracic volume manipulate the intrathoracic pressure
- Changes in pressure induce movement of air into/out of the lungs
- Anatomy:
- Twelve pairs of ribs (T1-12)
- All ribs attach posteriorly to the vertebral column
- True ribs (T1-7):
- Directly connect to the sternum
- Have their own cartilage
- False ribs (T8-10):
- Indirectly connect to the sternum
- Connect using the cartilage of superior ribs
- Floating ribs (T11/12):
- Do not connect to the sternum at all
- Sternal angle:
- Groove between the manubrium and the sternal body
- Manubrium ridges inferiorly and the sternum dips (can feel on patient’s chest)
- This is where T2 (second thoracic rib) joins the sternum
Breathing (external respiration):
- Alternating increase/decrease in thoracic volume, via movements of the thoracic wall
- Three planes of movement:
- Vertical (sagittal)
- Anteroposterior (coronal)
- Transverse (horizontal)
- Inspiration: diaphragm contracts, thorax volume increases, pressure drops, air enters
- Expiration: diaphragm relaxes, thorax volume decreases, pressure rises, air leaves
- NB. When atmospheric pressure is greater than lung pressure, air passively enters lung
3 Adapted from Lectures at the University of Leeds Medical School
RESPIRATORY
,Medic_Summaries (Body Systems)
Respiratory Strand
Respiratory system utilised for:
- Gas exchange
- Speech
- Smell
Functional divisions of the respiratory system:
- Conducting portion:
- From the nasal cavity to the terminal bronchi
- Transports air
- Conditions air (warm, moisten, filter)
- Has four paranasal sinuses (warm, moisten, filter)
- Sinus: space within skull
- Paranasal: next to the nasal cavity
- Respiratory portion:
- Thin, moist, delicate membrane (alveoli)
- Site of gaseous exchange
Conchae:
- Air passes into the nasal cavity over ridges called conchae
- These create turbulence and condition the air (warm, moisten, filter)
Problems:
- Pathogens thrive in this environment (pass in through sinuses and fester in mucus)
- Sinuses fill up from the bottom and therefore only empty when full
Frontal sinus: found in the frontal lobe
Ethmoidal cells: found in the bridge of the nose
Sphenoid sinus: found above the torus tubarius
Maxillary sinus: found above the maxilla (largest sinus)
Basic anatomy:
- Uvula hangs from roof of mouth (closes nasopharynx to stop food entering nasal cavity)
- Air passes down the pharynx to the oesophagus/trachea, passing the larynx (voice box)
- The trachea splits into two primary bronchi (left/right) before entering the lungs
- Mediastinum encloses the heart, major vessels, nerves, the trachea and the oesophagus
Lungs:
- Right lung:
- Trilobal (superior, middle and inferior lobes)
- Shorter, broader and larger
- An oblique fissure divides superior/inferior and middle/inferior lobes
- A horizontal fissure divides superior/middle lobes
- Left lung:
- Bilobal (superior and inferior lobes)
- Taller, narrower and smaller
- An oblique fissure divides superior/inferior lobes
2 Adapted from Lectures at the University of Leeds Medical School
, Medic_Summaries (Body Systems)
Medial view:
- Lung roots connect lungs to mediastinal structures
- Medial surface contains series of holes
- Most posterior is cartilaginous bronchi
Pulmonary arteries: take deoxygenated blood to the lungs
Pulmonary veins: take oxygenated blood away from the lungs
Conducting portion:
- Consists trachea and primary, secondary (lobar), tertiary (segmental) and terminal bronchi
- Where the trachea bifurcates is called the CARINA
- Within each lobe of a lung are a series of segments (each with separate arterial/air supply)
- If part of a lung gets damaged, the lung can still function (segmental damage)
Respiratory portion:
- Consists branches of terminal bronchioles to respiratory bronchiole/alveolar sacs
- Emphysema is an enlargement of the alveolar sacs, causing damage to the alveolar walls
- The hilum of the lung is the region through which structures comprising the lung root pass
Functional vs. anatomical:
- Functional:
- Conducting portion
- Respiratory portion
- Anatomical:
- Upper respiratory tract (URT) - nasal cavity to larynx/sinuses (common cold)
- Lower respiratory tract (LRT) - trachea to bronchi in lungs (pneumonia)
The thoratic cage:
- Functions:
- Protection:
- Forms a cage around vital organs (including upper abdominal organs)
- Respiration:
- Changes in thoracic volume manipulate the intrathoracic pressure
- Changes in pressure induce movement of air into/out of the lungs
- Anatomy:
- Twelve pairs of ribs (T1-12)
- All ribs attach posteriorly to the vertebral column
- True ribs (T1-7):
- Directly connect to the sternum
- Have their own cartilage
- False ribs (T8-10):
- Indirectly connect to the sternum
- Connect using the cartilage of superior ribs
- Floating ribs (T11/12):
- Do not connect to the sternum at all
- Sternal angle:
- Groove between the manubrium and the sternal body
- Manubrium ridges inferiorly and the sternum dips (can feel on patient’s chest)
- This is where T2 (second thoracic rib) joins the sternum
Breathing (external respiration):
- Alternating increase/decrease in thoracic volume, via movements of the thoracic wall
- Three planes of movement:
- Vertical (sagittal)
- Anteroposterior (coronal)
- Transverse (horizontal)
- Inspiration: diaphragm contracts, thorax volume increases, pressure drops, air enters
- Expiration: diaphragm relaxes, thorax volume decreases, pressure rises, air leaves
- NB. When atmospheric pressure is greater than lung pressure, air passively enters lung
3 Adapted from Lectures at the University of Leeds Medical School
