cardiac output and blood

phys lecture 4

functions of the cardiovascular system

• delivery of O2, glucose and other nutrients to active tissues

• removal of CO2, lactate and other waste products from active tissues 

• transport of metabolites and other substances to and from storage sites 

• transport of hormones, antibodies and other substances to site of action 

• moves blood to transport stuff in the blood 

total body water (tbw) of males and females

• 60% in males

• ~50% in females

distribution of body water between inside and outside of cells

• two thirds found in the ICF

• one third found in the ECF

extracellular fluid found in solid organs/ tissue is known as

interstitial fluid

plasma, lymph, and interstitial fluid are all components of:

the extracellular fluid

a person weighing 70kg holds about how many liters of blood?

5L

blood makes up what percentage of our body mass?

6-8%

percentage composition of plasma and cells in the blood:

• 55% plasma

• 45% cells

cells in the blood:

• erythrocytes (rbc)

• leukocytes (wbc)

• platelets

role of erythrocytes

• deliver oxygen and nutrients to the cells

• remove carbon dioxide and waste from the cells

role of leukocytes

immune response

role of platelets

blood clotting

arterioles

small arteries

venules

small veins

which blood vessels accept blood from the ventricles of the heart?

arteries

which blood vessels deliver blood to the atria of the heart?

ventricles

blood capillaries

where exchange of materials occur between the blood and body cells

systemic arteries have:

oxygenated blood

pulmonary veins have:

oxygenated blood

blood flow through the vascular system is produced by the (?) blood pressure

arterial to venous

high blood pressure in (1) vs low blood pressure in (2)

1. arteries

2. veins

diastole

• relaxation of the heart

• heart fills with blood

systole

• contraction of the heart

• heart empties out blood

diastolic pressure

lowest systemic arterial pressure during diastole (80mmHg avg)

systolic pressure

highest systemic arterial pressure during systole (120mmHg avg)

how to write blood pressure

systemic arterial pressure as systolic/ diastolic e.g. 120/80mmHg

pulse pressure

the difference between systolic and diastolic pressure (40mmHg)

mean arterial pressure

the arterial pressure averaged over the cardiac cycle (90-95 mmHg)

cardiac output

• the amount of blood pumped by the heart each minute

• flow rate out of one side of the heart by volume pumped per unit time

• cardiac output = stroke volume x heart rate

• 5-5.5L/min

stroke volume

• volume of blood pumped by a ventricle in one contraction

• 70-80ml avg

heart rate

• number of contractions per unit time

• generally beats per minute

• 70 beats/min avg

venous return

• flow rate into the heart

• 5-5.5L/min

end diastolic volume

• volume of blood present in the heart before it contracts

• the end volume of diastole

• ~130 ml

end systolic volume

• volume of blood present in the heart before it relaxes

• the end volume of systole

• ~50 ml

ejection fraction

~0.65 or 65%