WEEK 9: Thoracic cavity Flashcards
What is the thoracic region?
This is a cone shaped region that houses internal organs collectively called visceral organs. It is surrounded by the ribs and muscles of the chest.
what are the subdivisions of the thoracic cavity
Mediastinum cavity which contains the pericardial cavity (encloses heart and surrounds esophagus and trachea)
lateral pleural cavities
(contains each lung)
What are the membranes in the Pericardium cavity?
Serous membrane: name for thin double layered membrane
surrounding the walls of the ventral body cavity and the outer surfaces of organs
Parietal pericardium: layer of the serous membrane lining the cavity walls
Visceral pericardium: layer of the serous membrane clinging to an organs external surface within the ventral body cavity
Serous fluid: lubricating fluid that is secreted by both the parietal and visceral membranes. Its function is to allow the organs to slide without friction. This is particularly important for mobile organs such as the pumping of the heart and the churning of the stomach
what is a good annotation for the membranes associated with the pericardium cavity?
similar to putting your fist into a blown up balloon with your fist being the heart. The outer balloon wall is comparable to parietal pericardium while inner wall is similar to visceral pericardium.
What are the serosa membranes associated with the pleural cavity
Parietal pleurae
Visceral pleurae
What is the advantages of having body cavities?
- Body cavities confine organs with related functions to one area and support them
- Body cavities also reduce the spread of infection
what is the the mediastinum and what does it contain?
This is the area between the pleural sacs which extends from both medial surfaces of the lungs. This area mainly contains the heart.
label the heart and label these features:
Aorta, Brachiocephalic trunk, Left common carotid artery, superior vena cava, pulmonary vein.
….
Apart from from all the blood vessels in the heart, what are some other important features of the Mediastinum?
- Phrenic nerve: controls the diaphragm and keeps us breathing
- Vagus nerve: provides motor and sensory innervation to various organs in the body
- Trachea: passageway for air into the right and left bronchus which then travels into
the lungs - Oesophagus: carries food from the mouth to the stomach
Describe the structure of the pericardium and its function
The pericardium is a double-walled sac surrounding the heart which is split into superficial and deep parts.
Superficial fibrous pericardium
- loose fitting tough dense connective tissue
- protects, anchors and prevents overfilling of the heat
Deep serous pericardium
- contains visceral and parietal layers
what do cardiac veins form into to drain all the deoxygenated blood from the heart?
Coronary sinus
How do the parasympathetic and sympathetic NS get innervated by the heart?
The heart has both sympathetic and parasympathetic nerve supply (innervation)
Parasympathetic innervation of the heart- vagus nerve supplies most viscera in the thoracic & abdominal cavities
Sympathetic innervation of the heart – fibres from cervical trunk ganglia and merge to form a cardiac plexus for the heart
where is cardiac referred pain felt?
Cardiac referred pain is felt in the chest, arms, neck and especially the upper arm
