Higher Human Biology Subtopic 15 Cardiovascular Disease Physiology and Health Higher Human Biology Subtopic 15 Cardiovascular Disease

PPQ’s

vena cava prevents backflow of blood into the left ventricle /from the aorta ventricular systole

Learning Intentions To explain the process of atherosclerosis and its effect on arteries and blood pressure To explain what thrombosis is and the effect that it has on the arteries

Coronary Heart Disease Heart disease is a major problem in Scotland, especially in more deprived areas. Page 177

Atherosclerosis hardening of the arteries build up of fatty material (mainly cholesterol), fibrous material and calcium. forms an atheroma (or plaque) under the epithelium lining the artery.

Large atheromas…… Lead to : Narrowing of the lumen Restriction of blood flow increase in blood pressure

Large plaques can harden Arteries lose elasticity Symptoms may go unnoticed!

Contributing factors to the development of atherosclerosis High blood pressure Carbon monoxide in cigarettes Diabetes High blood cholesterol levels

Consequences Atherosclerosis can lead to the development of various cardiovascular diseases like: Coronary heart disease (including angina) Strokes Heart attacks (myocardial infarction) Peripheral vascular disease

Blood Clotting Protective mechanism to prevent blood loss The enzyme, prothrombin, is inactive in the blood. To clot blood… Prothrombin (inactive enzyme) Clotting factors Thrombin (active enzyme) Fibrinogen (soluble protein) Fibrin (insoluble protein) Sticky web forms a clot

Thrombosis Atheroma's make inside the arteries uneven and disrupt blood flow It can burst through the endothelium and damage it. Thrombosis (the formation of a blood clot in a vessel) may occur

Thrombosis

Embolus When a thrombus breaks loose It travels through the blood and can block arteries

Coronary thrombosis The coronary artery supplies oxygenated blood to the heart. If the embolus blocks a coronary artery it may lead to a heart attack.

Connects the aorta to the coronary artery using a vein from the leg

Stroke If a blood clot blocks an artery supplying the brain, this can lead to a stroke. In both heart attack and stroke, tissue death can occur due to a lack of oxygen.

Peripheral Vascular Disease Narrowing of the other arteries (not those to the heart and brain) Mostly affects the legs Pain starts due to restricted oxygen supply to the cells (e.g. in exercise)

Deep Vein Thrombosis A blood clot that forms in a deep vein most commonly in the leg. The leg can become swollen with blood and if the clot breaks off this can result in a pulmonary embolism.

This can be treated using anticoagulant drugs Pulmonary Embolism This can be treated using anticoagulant drugs

Learning Intentions To explain the process of atherosclerosis and its effect on arteries and blood pressure To explain what thrombosis is and the effect that it has on the arteries

The Heart….Bingo !! Thrombus Stroke Thromboplastin Sympathetic Parasympathetic Vasoconstriction Vasodilation Atherosclerosis Systolic Stroke volume Cardiac output Artery Vein Capillary Hepatic portal vein Sinoatrial node Atrioventricular node Noradrenaline Acetylcholine CAC CIC Hypertension Pulmonary artery Pulmonary vein