Category: GCE A-level Biology

Allergy means ‗altered reaction‘ – it is the inappropriate and harmful response of the body‘s defence mechanisms to

the term antibiotic strictly refers to substances that are of biological origin whereas the term chemotherapeutic agent refers

ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS) caused by HIV; the virus infects and destroys cells of the body‘s immune system

Causes of TB TB is caused by two bacteria; Mycobacteria tuberculosis and Mycobacteria bovis. Tuberculosis is ultimately caused

malaria is caused by a single celled organism called the organism is transmitted from one person to another

Why infectious diseases are the leading causes of death in developing countries infectious disease are communicable/transmittable; pathogens spread

Cholera is a water-borne disease caused by a bacterium. It often appears in a population following a natural

Drugs   any man-made chemical taken into the body, (broadly) any chemical substance taken into the body; but

Effects of tar in tobacco smoke on the gaseous exchange system stimulates extra cell division +thickening of the