Effects of lifestyle choices Multicellular organisms – section 7

Learning outcomes Explain how poor diet and lack of exercise can affect transport and exchange systems, and cause diseases Explain how smoking tobacco and drinking alcohol can affect transport systems and cause diseases

Diet A balanced diet is very important FAT: Excess fat in the diet can lead to obesity and increased cholesterol in the blood - cholesterol can be deposited in arteries, forming plaques - this can lead to atherosclerosis - arteries narrow and can become blocked SALT: High salt intake increases blood pressure - this strains the heart and arteries - increased risk of heart attack & stroke

exercise Regular exercise helps blood circulation - reduced risk of DVT (deep vein thrombosis) Also helps reduce the chance of obesity Reduces risk of: - type 2 diabetes - heart disease - certain cancers

smoking Cigarette smoke contains 1000’s of harmful chemicals, which include: Carbon Monoxide: - reduces ability of cells to carry oxygen Tar: - builds up in the lungs, and can cause cancer - also damages cilia (normally sweep away mucus) Nicotine: - very addictive Also many other poisonous/toxic chemicals – e.g. heavy metals, arsenic

alcohol Excess alcohol consumption has many health risks: Increased risk of stroke - “binge” drinking increases blood pressure Increases risk of type 2 diabetes Increased risk of atherosclerosis & heart attack Increased risk of cirrhosis – irreversible liver damage Can affect mental health – e.g. cause depression Increased risk of certain cancers Short term effects: - blurred vision, impaired judgement, poor balance & co-ordination