Download presentation
Presentation is loading. Please wait.
Published byClyde Garrison Modified over 8 years ago
1
EDU2HBS Human Body Systems 1 Cardiovascular System
2
EDU2HBS Human Body Systems 2
3
3 The Cardiovascular System A closed system of the heart, blood and blood vessels The heart pumps blood Blood vessels allow blood to circulate to all parts of the body The function of the cardiovascular system is
4
EDU2HBS Human Body Systems 4 Color range pH must remain between 7.35–7.45 Blood temperature is slightly higher than body temperature The Blood ( Physical Characteristics)
5
EDU2HBS Human Body Systems 5 Blood Plasma Includes many dissolved substances Nutrients Salts (metal ions) Respiratory gases Hormones Proteins Waste products
6
EDU2HBS Human Body Systems 6 Erythrocytes (Red Blood Cells) Outnumber white blood cells 1000:1 Contain a protein chemical called hemoglobin Make blood bright red Contains the element iron which carries oxygen
7
EDU2HBS Human Body Systems 7 Leukocytes (White Blood Cells) Platelets occurs when blood vessels are ruptured.
8
EDU2HBS Human Body Systems 8 The Heart Location Thorax between the lungs Pointed apex directed toward left hip About the size of your fist
9
EDU2HBS Human Body Systems 9 The Heart: Coverings Pericardium – a double walled membrane Visceral pericardium Parietal pericardium Serous fluid fills the space between the layers of pericardium
10
EDU2HBS Human Body Systems 10 The Heart: Heart Wall Three layers Epicardium Outside layer This layer is the parietal pericardium Myocardium Middle layer Endocardium Inner layer
11
EDU2HBS Human Body Systems 11 External Heart Anatomy
12
EDU2HBS Human Body Systems 12 The Heart: Chambers Four chambers Atria Receiving chambers Right atrium Left atrium Ventricles Discharging chambers Right ventricle Left ventricle
13
EDU2HBS Human Body Systems 13 Blood Circulation
14
EDU2HBS Human Body Systems 14 The Heart: Valves Four valves Atrioventricular valves – between atria and ventricles Mitral valve (left) Tricuspid valve (right) Semilunar valves between ventricle and artery Pulmonary semilunar valve Aortic semilunar valve
15
EDU2HBS Human Body Systems 15 The Heart: Valves Valves open as blood is pumped through Close to prevent backflow
16
EDU2HBS Human Body Systems 16 Coronary Circulation The heart has its own nourishing circulatory system Coronary arteries Cardiac veins Blood empties into the right atrium via the coronary sinus
17
EDU2HBS Human Body Systems 17 The Heart: Conduction System Intrinsic conduction system (nodal system) Heart muscle cells contract, without nerve impulses, in a regular, continuous way
18
EDU2HBS Human Body Systems 18
19
EDU2HBS Human Body Systems 19 Heart Contractions Sequential stimulation occurs at other autorhythmic cells AV node AV bundle Bundle branches Purkinje fibres
20
EDU2HBS Human Body Systems 20 The Heart: Cardiac Output Cardiac output (CO) CO = (heart rate [HR]) x (stroke volume [SV]) Stroke volume
21
EDU2HBS Human Body Systems 21 The Heart: Regulation of Heart Rate Starling’s law of the heart – the more that the cardiac muscle is stretched, the stronger the contraction Changing heart rate is the most common way to change cardiac output
22
EDU2HBS Human Body Systems 22 The Heart: Regulation of Heart Rate Increased heart rate Sympathetic nervous system Crisis Low blood pressure Hormones Epinephrine Thyroxine Exercise Decreased blood volume
23
EDU2HBS Human Body Systems 23 The Heart: Regulation of Heart Rate Decreased heart rate Parasympathetic nervous system High blood pressure or blood volume Decreased venous return
24
EDU2HBS Human Body Systems 24 Blood Vessels: The Vascular System Taking blood to the tissues and back Arteries Arterioles Capillaries Venules Veins
25
EDU2HBS Human Body Systems 25 Differences Between Blood Vessel Types Walls of arteries are the thickest Lumens of veins are larger Walls of capillaries are only one cell layer thick to allow for exchanges between blood and tissue
26
EDU2HBS Human Body Systems 26 Movement of Blood Through Vessels Most arterial blood is pumped by the heart Veins use the milking action of muscles to help move blood Figure 11.9
27
EDU2HBS Human Body Systems 27 Capillary Beds Capillary beds consist of two types of vessels 1. Vascular shunt – directly connects an arteriole to a venule
28
EDU2HBS Human Body Systems 28 Capillary Beds 2. True capillaries – exchange vessels Oxygen and nutrients cross to cells Carbon dioxide and metabolic waste products cross into blood Figure 11.10
29
EDU2HBS Human Body Systems 29 Pulse Monitored at “pressure points” where pulse is easily palpated
30
EDU2HBS Human Body Systems 30 Blood Pressure Pressure in blood vessels decreases as the distance away from the heart increases
31
EDU2HBS Human Body Systems 31 Blood Pressure: Effects of Factors Neural factors Autonomic nervous system adjustments (sympathetic division) Renal factors Regulation by altering blood volume Renin – hormonal control
32
EDU2HBS Human Body Systems 32 Blood Pressure: Effects of Factors Temperature Heat has a vasodilation effect Cold has a vasoconstricting effect Chemicals Various substances can cause increases or decreases Diet
33
EDU2HBS Human Body Systems 33 Factors Determining Blood Pressure
34
EDU2HBS Human Body Systems 34 Variations in Blood Pressure Human normal range is variable Normal 140–110 mm Hg systolic 80–75 mm Hg diastolic Hypotension Low systolic (below 110 mm HG) Often associated with illness Hypertension High systolic (above 140 mm HG) Can be dangerous if it is chronic
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.