2. What Does C-V System do?
• Circulate blood throughout entire body
for
– Transport of oxygen to cells
– Transport of CO2 away from cells
– Transport of nutrients (glucose) to cells
– Movement of immune system components
(cells, antibodies)
– Transport of endocrine gland secretions
3. How does it do it?
• Heart is pump
• Arteries and veins are main tubes (plumbing)
– Arteries Away from Heart
– Veins to Heart
• Diffusion happens in capillaries (oxygen,
CO2, glucose diffuse in or out of blood)
4. Overall Organization of System
• Heart/Great Vessels--
1 Route
• Smaller aa. vv.--many
routes (collateral
circulation)
• Capillaries—network
where diffusion
occurs
7. Artery/Vein differences
Arteries (aa.) Veins (vv.)
Direction Blood Away from Blood to Heart
of flow Heart
Pressure Higher Lower
Walls THICKER: Tunica THINNER: Tunica
media thicker than externa thicker
tunica externa than tunica media
Lumen Smaller Larger
Valves No valves Valves (see next)
8.
9. Capillaries
• Microscopic--one
cell layer thick
• Network
• Bathed in
extracellular matrix
of areolar tissue
• Entire goal of C-V
system is to get
blood into
capillaries where
diffusion takes
place
13. Right Heart Chambers: Pulmonary Circuit
• Right Atrium (forms most of posterior of heart)
– Receives O2-poor blood from body via IVC, SVC, Coronary sinus
– Ventral wall = rough Pectinate muscle
– Fossa Ovalis- on interatrial septum, remnant of Foramen Ovale
• Right Ventricle
– Receives O2-poor blood from right atrium through tricuspid valve
– Pumps blood to lungs via Pulmonary Semilunar Valve in
pulmonary trunk
– Trabeculae Carnae along ventral surface
– Papillary Muscle-cone-shaped muscle to which chordae tendinae
are anchored
– Moderator Band-muscular band connecting anterior papillary
muscle to interventricular septum
14. Left Heart Chambers: Systemic Circuit
• Left Atrium
– Receives O2-rich blood from 4 Pulmonary Veins
– Pectinate Muscles line only auricle
• Left Ventricle (forms apex of heart)
– Receives blood from Left Atrium via bicuspid valve
– Pumps blood into aorta via Aortic Semilunar Valve to body
– Same structures as Rt Ventricle: Trabeculae carnae,
Papillary muscles, Chordae tendinae
– No Moderator Band
15. Heart Valves: Lub*-Dub**
• *Tricuspid Valve: Right AV valve
– 3 Cusps (flaps) made of endocardium and CT
– Cusps anchored in Rt. Ventricle by Chordae Tendinae
– Chordae Tendinae prevent inversion of cusps into atrium
– Flow of blood pushes cusps open
– When ventricle in diastole (relaxed), cusps hang limp in ventricle
– Ventricular contraction increases pressure and forces cusps closed
• *Bicuspid (Mitral) Valve: Left AV valve
– 2 cusps anchored in Lft. Ventricle by chordae tendinae
– Functions same as Rt. AV valve
• **Semilunar valves: prevents backflow in large arteries
– Pulmonary Semilunar Valve: Rt Ventricle and Pulmonary Trunk
– Aortic Semilunar Valve: Left Ventricle and Aorta
– 3 cusps: blood rushes past they’re flattened, as it settles they’re pushed
down (valve closed)
18. Location of Heart in Chest
• Oblique Position
• Apex = Left of Midline (5th ICS), Anterior to rest of heart
• Base (posterior surface) sits on vertebral column
• Superior Right = 3rd Costal Cartilage, 1” right midsternum
• Superior Left = 2nd Costal Cartilage, 1” left midsternum
• Inferior Right = 6th Costal Cartilage, 1” right midsternum
• Inferior Left = 5th Intercostal Space at Midclavicular line
19. • Epicardium (most
superficial)
– Visceral pleura Heart Wall
• Myocardium (middle layer)
– Cardiac muscle
– Contracts How does heart
• Endocardium (inner) muscle get blood
– Endothelium on CT supply?
– Lines the heart
– Creates the valves
pg 524
20. Blood supply to heart wall
• Rt and Lft Coronary Arteries
– Branch from Ascending Aorta
– Have multiple branches along heart
– Sit in Coronary Sulcus
– Coronary Heart Disease
• Cardiac Veins
– Coronary Sinus (largest)
– Many branches feed into sinus
– Sit in Coronary Sulcus
21. Heart Innervation
• Heart receives visceral
motor innervation
– Sympathetic (speeds up)
– Parasympathetic (slows
down) p. 534
25. Lymphatic System…The Players:
• Lymph- clear fluid from loose areolar CT around
capillaries
• Lymphatic capillaries (near blood capillaries)
• Lymph collecting vessels (small, 3 tunicas, valves)
• Lymph nodes (sit along collecting vessels)-clean
lymph of pathogens, they are NOT glands
• Lymphatic trunks (convergence large collecting
vessels)
– Lumbar, intestinal, bronchomediastinal, subclavian, jugular
• Lymphatic ducts empty into veins of neck
26. Lymphatic System--Function
• Function: to collect excess tissue fluid collecting at
arteriole end and return leaked blood proteins to
blood (maintain osmotic pressure needed to take
up water into bloodstream)
• Lymph moved through vessels
– Pulse of nearby arteries
– Contraction of surrounding skeletal muscle
– Regular movement of body (wiggling legs)
– Muscle in Tunica Media
• Lacteals-lymphatic capillaries w/unique function
– In mucosa of small intestine, receive digested fat from
intestine
– Fatty lymph becomes milky = Chyle
– Chyle goes to bloodstream
