14Blood The human body has 4-6 liters of blood Blood: 45% of blood is Cells55% of blood is plasma
15Blood Cells: 3 kindsRed Blood Cells: transports oxygen, contain hemoglobin (gives them color)White Blood Cells (leukocytes): attack foreign substances or organisms.Platelets: stick to broken blood vessels to stop bleeding when you are cut
19The Heart The human heart has four chambers Left and right ventricle Left and right atriumThe left side of the heart pumps oxygenated blood to the bodyThe right side of the heart pumps deoxygenated blood to the lungs
30Blood PressureBlood pressure is a measure of the force exerted by the blood on the wall of the arteries.An example is 120/80 (systolic pressure/diastolic pressure.Systolic pressure is the result of the contraction of the ventricles (normal )Diastolic pressure is during the ventricle relaxation (normal 70-90)
31Disorders of the Circulatory System: Coronary artery disease – Atherosclerosis Plaque buildup blocks arteries, reducing, or even stopping blood flowPlaques can break off, causing heart attack or stroke
32Cause: Damaged arteries are ‘invaded’ by bad LDL cholesterol Cause: Damaged arteries are ‘invaded’ by bad LDL cholesterol. White blood cells try to digest the LDL. Ultimately, a jumble of cholesterol and cells is accumulated.Risk Factors: Smoking, high blood pressure, high LDL cholesterol, diabetes
33Disorders of the Circulatory System Heart Attack– Myocardial Infarction (MI)= Death of cardiac muscle cellsCause: Plaque dislodges, blocking an artery to the heart muscle. Cardiac muscle cells are starved for oxygen and die. After, scar tissue forms where cells died, therefore reduces the functionality of heart.Severity of a heart attack depends on size and area supplied by the artery.Risk Factors: Smoking, high blood pressure, high LDL cholesterol, diabetes
34Disorders of the Circulatory System Stroke=Death of cells in the brain.Cause: A blood vessel in the brain is blocked (by dislodged plaque, or bursts, starving the cells of oxygenA stroke can have many different symptoms, including: numbness, vision changes, speech changes, or confusion.Risk Factors: Smoking, high blood pressure, high LDL cholesterol, diabetes
35Disorders of the Circulatory System Arrhythmia= Irregular / skipped heart beatCause: The heart uses electrical signals created in the SA node in the right atria, to begin a heartbeat. The conduction of these signals, or irregular firing of the SA node, can cause arrhythmias. Atrial arrhythmias are less dangerous than ventricular arrhythmias.Risk Factors: Generally random, but factors are stimulants (such as caffeine), fevers, stress, or genetic disorders.
37Disorders of the Circulatory System High blood pressure - HypertensionDiastolic pressure over 90Why it is dangerous: Excessive pressure can cause the arteries to thicken, and blood vessels to weaken and rupture. This can lead to heart failure, stroke, kidney failure, loss of sight when vessels in eyes burst.Risk Factors: Genetics, overweight, limited physical activity, smoking, alcohol consumption, certain medicationsVirtual Cardiology Lab
38Respiratory System Function: Bringing Oxygen into the body, and removing carbon dioxide and water vapor.
39Respiratory System What gases are in our atmosphere? 78% Nitrogen 21% Oxygen1% Argon
40Respiratory System Structures: Nose Pharynx larynx trachea bronchi bronchioleslungs