Lifestyle, disease, diet and health Flashcards
How is BMI measured?
BMI = body mass/kg / height2/m2
What is BMI not accurate for?
Athletes, children, people over 60 or people with long term heart conditions.
How are lipoproteins formed (soluble cholesterol)?
Cholesterol (insoluble) + Hydrophilic globular protein (soluble) = Lipoprotein (soluble)
How does obesity increase blood pressure?
Blood vessels are longer, so the heart must pump harder to counteract peripheral resistance.
What are unstable radicals?
Atoms with unpaired electrons, which result from reactions in the body.
- Highly reactive, can damage cell components like enzymes.
- This damage has been linked to dev. of cancer, CHD.
How can free radicals be counteracted?
Vitamins like Vit C, beta-carotene which provide hydrogen atoms that stabilise the radical theough bonding.
Why is a high salt diet a risk factor for CVD?
High salt diet causes kidneys to retain water, higher fluid levels in the blood cause hypertension.
Why is stress a risk factor for CHD?
Release of adrenaline causes arteries and arterioles to constrict, raising BP. Stress can also lead to more alcohol consumption or overeating.
Why is alcohol a risk factor for CVD?
- Direct tissue damage
- Hypertension
- Contributes to obesity
- Irregular heartbeat
What effect do the genes APOA, APOB, APO E have when inherited?
Apoa-Produces protein component of HDL, less HDL production so less LDL removed.
Apob-Produces protein component of LDL, LDLs are the wrong shape to bind to receptors so they circulate in blood.
Apoe-Produces protein component of LDL & HDL, allele 4 slows LDL removal.
Outline a drug that controls blood pressure
ACE inhibitors
Effect - Lowers bp.
How - Reduces production of angiotensin 2, which causes vasoconstriction.
SE - Reduction in kidney function, dizziness, dry cough.
Outline a diuretic drug
Diuretics
Effect - Decrease in blood plasma volume and cardiac output, lowers BP.
How - Increases urine volume, rids body of excess salt and fluids.
SE - Dizziness, cramp, nausea.
Outline a drug that reduces BC
Statins
Effect - Lowers BC.
How - Inhibit enzymes involved in LDL production in the liver.
SE - Vomiting, diarrhoea, headache.
Very briefly outline atherosclerosis
- Irritants, high LDL, cig smoke or high BP.
- Endothelium damaged.
- Inflammatory resp. - WBCs enter artery wall.
- Cholosterol accum. due to WBCs, causing atheroma to form.
- Ca2+ and fibrous tissue accum. causing hard plaque - limits artery elasticity, higher BP.
- Plaques narrow lumen, rise in BP, more stress on other lumens - more plaques.
What is the function of blood clotting?
Seals breaks in blood vessels and prevents pathogen entry.
Describe the clotting cascade.
- Platelets and damaged tissue release thromboplastin protein.
- Thromboplas. activates enzyme that catalyses conversion of prothrombin –> thrombin (VIT K AND CA2+ IONS MUST B PRESENT).
- Thromb. catalyses conversion of soluble plasma protein fibrinogen into insoluble protein fibrin.
- Mesh of fibrin forms –> traps platelets and RBCs to form a clot.
How does smoking increase risk?
CO combines with haemoglobin and reduces the amount of oxygen available to tissues. Nicotine makes platelets more sticky –> blood clots more likely
How is the waist to hip ratio measured?
Waist circumference divided by hip circumference
Describe the two different types of cholesterol
HDL: decreases chol. levels when they’re too high and transports chol. to the liver where it’s excreted or recycled. Composed mainly of protein.
LDL: increases chol. levels when they’re too low and transports chol. from the liver into the bloodstream. Composed mainly of lipid.
