MYP Biology Factors Affecting Human Health Notes

What Factors Affect Human Health?

1. Human health is not defined only by the absence of disease.
   1. Health includes physical, mental, and social well-being.
   2. All body systems must function effectively to maintain homeostasis.
   3. Mental and emotional stability affects how the body responds to stress and illness.

How Do Genetic Factors Affect Human Health?

1. Some diseases are inherited:
   1. Caused by mutations in genes.
   2. Passed from parents to offspring.
   3. Cannot be transmitted between individuals.
2. Genetic conditions affect cell function:
   1. Faulty proteins are produced.
   2. Normal physiological processes are disrupted.

How Do Lifestyle Choices Affect Human Health?

1. Diet influences long-term health
   1. Balanced diets support growth, repair, and immune function.
   2. Excess salt increases blood pressure.
   3. Excess sugar increases risk of obesity and type 2 diabetes.
   4. High saturated fat intake increases cardiovascular disease risk.
2. Physical activity affects body systems
   1. Regular exercise strengthens the heart and lungs.
   2. Sedentary lifestyles increase obesity risk.
   3. Muscle and bone strength decline without activity.
3. Smoking and alcohol impact multiple organs
   1. Smoking damages lung tissue and increases cancer risk.
   2. Alcohol damages liver cells and impairs nervous system function.

How Does Mental Health Influence Physical Health?

1. Mental health affects physiological processes
   1. Chronic stress weakens immune responses.
   2. Hormonal imbalance affects sleep and digestion.
2. Emotional resilience supports overall health
   1. Strong social support reduces stress effects.
   2. Isolation increases risk of mental and physical illness.

How Does The Environment Affect Human Health?

1. Air quality influences respiratory and cardiovascular health
   1. Pollution damages lung tissue.
   2. Long-term exposure increases heart disease risk.
2. Water quality and sanitation affect disease risk
   1. Clean water prevents waterborne illness.
   2. Poor sanitation increases exposure to harmful microorganisms.
3. Climate affects health patterns
   1. Higher temperatures expand habitats of disease vectors.
   2. Heatwaves increase dehydration and cardiovascular strain.

How Do Socio-Economic Factors Affect Health?

1. Income influences access to resources
   1. Healthcare availability.
   2. Nutritious food.
   3. Safe housing.
2. Education affects health decisions
   1. Understanding of nutrition and disease prevention.
   2. Likelihood of seeking medical care early.
3. Healthcare access shapes outcomes
   1. Preventative care reduces severe illness.
   2. Vaccination coverage improves population health.

Why Does Health Vary Between Populations?

1. Geographic location affects health risks
   1. Rural areas may lack healthcare infrastructure.
   2. Urban areas may experience higher pollution levels.
2. Cultural practices influence health behaviours
   1. Traditional diets affect nutrient intake.
   2. Beliefs influence use of medical services.

How Do Lifestyle And Environment Interact?

1. Food availability shapes diet
   1. Food deserts limit access to fresh produce.
   2. Processed foods become default options.
2. Urban design influences physical activity
   1. Walkable cities encourage movement.
   2. Unsafe environments discourage exercise.
3. Housing conditions affect respiratory health
   1. Poor ventilation increases respiratory stress.
   2. Damp environments worsen asthma symptoms.