Health, disease and the development of medicines study guide

Cardiovascular disease (CVD) treatments are grouped into lifestyle changes, lifelong medication, and surgical procedures. Each has its own strengths, risks, and long-term effects. Lifestyle changes focus on healthy diet, exercise, and quitting harmful habits, aiming to lower risk factors in a non-invasive way. Medications such as statins and antihypertensives can reduce risk or control symptoms, sometimes for life, but may produce side effects and require strict adherence. Surgical procedures, like angioplasty with stents and coronary artery bypass, are reserved for severe cases where other strategies are not enough. They have clear benefits for restoring blood flow but involve surgical risks and longer recovery. Effectiveness, patient suitability, and impact on quality of life must be considered when making treatment decisions.

When investigating how antiseptics, antibiotics, or plant extracts affect microbial cultures, use standard aseptic techniques (disinfecting work areas, wearing gloves and goggles, using sterilised tools) and only permitted, non-pathogenic bacterial species. The independent variable is the type or concentration of antimicrobial agent, and the dependent variable is the zone of inhibition (clear area around the disc) on an agar plate. Control all possible variables, such as the same bacterial strain, agar depth and composition, incubation time, and disc size and placement. Carefully inoculate plates, add antimicrobial discs and a control, seal plates with tape, and label clearly. Incubate plates upside down at or below 25°C for safety. After incubation, do not open the plate – measure the inhibition zone diameter through the closed lid using a ruler. For graphical presentation: display antimicrobial type or concentration on the x-axis and mean zone diameter on the y-axis as a bar graph or line graph. Evaluate the reliability by repeating the experiment, calculating averages, and comparing data; assess uncertainty by comparing the ruler precision (for example, ±1 mm) to the measured zone, then calculate percentage error as (uncertainty/mean) × 100%. Dispose of all cultures and materials by sterilisation (e.g., autoclave) under supervision. Never incubate plates above 25°C or open plates after incubation in schools.