Blood and Blood Pressure

Components of Blood Plasma – Liquid portion of blood – Contains ions, proteins, hormones Cells – ___________________________________ Contain hemoglobin to carry oxygen – ____________________________________ Important for fighting infection and your immune system – _______________________________________ Important in blood clotting

Pathway of Blood through the heart

Cardiac Cycle Is a series of events that occurs through one heart beat. ___________~ phase of relaxation – ventricles relax - heart is filling with blood ___________~ phase of contraction – ventricles contract - the heart ejects the blood

Blood Pressure changes in pressure within the heart – ____________________________________________ _____________ force blood against artery walls Systolic BP (__________________) over Diastolic BP (______________) normal BP ~ ________________________ (millimetres of mercury )millimetres of mercury increases during exercise consistently high BP = HYPERTENSION – 140/90mmHg – major risk of cardiovascular disease

Taking Blood Pressure

Cardiac Output (Q) volume of blood pumped out of the _____________________________________ measured: L/min at rest ~ ____________________ Two factors that contribute to cardiac output: 1.Stroke Volume (SV) 2.Heart Rate (HR)

Stroke Volume amount of blood that is ejected from the left ventricle in a single beat measured in ______________ Heart Rate The ___________________the heart contracts in a minute (beats/min)

Calculating Cardiac Output Cardiac output is the product of stroke volume and heart rate: Q (L/min) = __________________________ Example: HR at rest ~72 beats/min, SV at rest ~71 mL

Cardiac Output and Exercise Q increases to ______________(depending on intensity of exercise) Q increases then becomes constant SV increase occurs early in exercise and plateaus HR increases early (same as above) Prolonged exercise SV might decline late in exercise (due to excessive fluid loss form body – sweating) – Q is maintained because HR increases