B5H common assessment
Organ replacement
Y11 Biology
Organ replacement
This is a revision guide of B5H and includes everything you need to know about organ replacement . Organ replacement is important because if one organ stops working the body can stop functioning , so if the organ can be replaced the person can carry on living an active life for many more years .
Mechanical replacements
Mechanical replacement is when plastic / metal is used to replace joints .
People with cataracts can be given plastic eye lenses . You can get a plastic and metal heart to pump blood around the body when the heart has failed . This is done until a heart transplant can be found . The original heart may be left and an artificial pump is attached to remove some of the workload . This can sometimes allow a heart to repair itself
Other examples are:
* Knee and hip joints can be replaced with plastic/metal joints
* Pancreas
* Ovaries
* Ear – cochlear implant
Mechanical joints are made from bio-inert materials . Bio-inert materials are not easily damaged by body fluids and won’t be attacked by the immune system . Many plastics are bio-inert and so are metals such as gold and titanium.
Outside the body mechanical replacements
During heart surgery the heart needs to be stopped as it is difficult to perform surgery on the heart if it is moving . The blood still needs to be pushed around the body so a heart-lung machine is used . A iron lung is another machine used for people who cannot breathe for themselves . A pump increases and decreases the pressure . When the pressure is raised , the air is pushed out the lungs . When the pressure is lowered , the air flows into the lungs. A artificial kidney has not be designed that works outside the body , so a dialysis machine is used for people who kidneys have stopped working. A dialysis machine has to be done regularly and this is to keep the concentrations of dissolved substances in the blood at normal levels and remove waste substances .
