Ventilation Ventilation?can be defined as The replacement of older air in the lungs with fresh air from the body's external environment Ventilation is essential for the effective?exchange of gases?...
Antibiotic Resistance Within a bacterial population, there is?variation?caused by?mutations?(as occurs in populations of all species) A chance mutation might cause some bacteria to become?resistant...
Antibiotics Antibiotics?are?drugs?that?inhibit the growth?of microorganisms Most antibiotics?kill or stop the growth of bacteria?(prokaryotes) but do not harm the cells of the infected organism Thi...
White Blood Cells Phagocytes?are white blood cells that are produced continuously in the?bone marrow They are responsible for?removing dead cells and invasive microorganisms;?a?non-specific immune ...
Platelets When the skin is cut, microorganisms have an entry point to get into the body The first line of defence is compromised In order to minimise the risk of substantial?blood loss?and entry of...
Skin The?skin and mucous?membranes form a?primary defence?against pathogens that cause infectious disease Skin?is the largest organ of the body and is covered in?microorganisms?that usually cause n...
The Structure of the Heart Heart structure The heart has?two sides: The?left?side pumps?oxygenated?blood around the body in the?systemic circulation The?right?side pumps?deoxygenated?blood to the l...
Heart Rate: Alteration by Nervous System Although the heart muscle maintains a base heart rate via?myogenic?stimulation, there are several circumstances that can cause an individual's heart rate to...
Introduction to the Heart Mammalian heart structure The heart is a hollow,?muscular organ?located in the chest cavity The heart is divided into?four chambers The two top chambers are?atria The bott...
