Future Performance Training
The body has many cavities but the most important two (2) are the dorsal and ventral cavities:
- Dorsal Cavities: This cavity is situated posteriorly and is divided into two smaller cavities.
o Cranial cavity ‑ Houses the brain and specialised membranes - Dura Mater, Pia Mater and Arachnoid.
o Spinal cavity ‑ Running through the centre of the back bone; protecting the spinal cord and its specialised membranes.
- Ventral Cavities: This cavity is situated anteriorly and is also divided into two smaller cavities.
o Thoracic cavity ‑ This cavity is subdivided again into smaller cavities which contain the heart (pericardial cavity), lungs (2 pleural cavities), major blood vessels, part of the trachea and oesophagus (mediastinum).
o Abdominopelvic cavity ‑ This cavity consists of two parts and is not physically separated. The abdominal cavity contains the liver, stomach, gall bladder, pancreas, spleen, small intestine and most of the large intestine. The pelvic cavity contains the bladder, large intestine and female reproductive organs. The kidneys are not found in the abdominal cavity but lie behind the peritoneal membrane (posteriorly).
The Abdominopelvic Quadrants
The abdominopelvic region is divided into four quadrants and is named after their position, i.e. right and left upper quadrants and right and left lower quadrants.
The skeleton consists of 206 bones.
Functions of the Skeleton
- Protect the delicate organs
- Framework and support ‑ gives shape and rigidity to the body.
The Skeleton
Functions of the Skeleton
- Protect the delicate organs.
- Framework and support ‑ gives shape and rigidity to the body.
- Aids in movement ‑ muscles attach to bones.
- Marrow of certain bones produce red blood cells and some white blood cells.
- Storage place for minerals, esp. calcium and phosphorus.
The Cranium (Skull)
THE CRANUIM
The Spinal Column.
The spinal column consists of 33 vertebrae which are divided into:
- Functions of the Spinal Column:
o Separate vertebrae form a column to protect the nerves.
o Allows movement in all directions.
o Forms a framework where other bones are attached and the cranium is carried by the spine.
The spinal discs act as shock absorbers (e.g. during the carrying of heavy objects).
The Pelvic Girdle
Functions of the Cardiovascular System
- Transport of body substances
- Regulation of body temperature.
The Cardiovascular System consists of
- The Heart
o Approximately the size of a man's fist.
o The contraction action pumps blood through the body.
o Comprises of four (4) chambers:
o 2 Atria (upper half of the heart)
o 2 Ventricles (lower half of the heart)
o Atria receive incoming blood.
o Ventricles pump blood out (stronger heart muscles).
o Right hand side receives de‑oxygenated blood, from the body and pumps to the lungs.
o Left hand side receives oxygenated blood, from the lungs and pumps it to the body.
- The Blood Vessels
o Arteries.
o Capillaries.
o Veins.
The average adult has 71 ml / kg of blood in his / her circulatory system.
The ideal pulse for an adult is 60 – 100 beats per minute. It is usually felt for at one of the following places: the neck (carotid pulse) for unresponsive patients or wrist (radial pulse) for responsive patients.
Functions of the Respiratory System
- To supply the body's tissue with vital oxygen
- To remove waste gases from the body
- Responsible for the ability to communicate.
Breathing
When one breathes in, air is passed through the nose and mouth and passes into the pharynx. The pharynx separates into two passageways, one being the oesophagus and the other the trachea. The trachea lies in front of the oesophagus.
From the trachea, the air enters the lungs through the left and right main bronchi. The bronchi tubes divide to smaller tubes called the bronchiole. At the end of these bronchiole are tiny sacs, called alveoli. The gas exchange takes place here with oxygen and carbon dioxide moving through the walls of the alveoli and capillaries. The oxygen enters the blood stream and circulates throughout the entire body feeding all the body’s vital organs and tissue. Once the oxygen in the blood has been used, a by-product carbon dioxide is deposited in the blood for the return trip to the lungs. When the person exhales the unused portion of oxygen and carbon dioxide leave the body through the airway.
FIGURE 9: THE RESPIRATORY SYSTEM
Typically, adults breath approximately between 12 - 20 breaths per minute (1 breath every 5 seconds) and children and infants 20 - 30 breaths per minute (1 breath every 3 seconds), under normal circumstances and is largely an automatic process.