the cardiovascular system blood the heart blood vessels
TRANSCRIPT
The Cardiovascular System
Blood
The Heart
Blood Vessels
Cardiovascular system
Functions:
Transports:
oxygen
carbon dioxide
nutrients
wastes
chemical messengers
Homeostasis of
pH
temperature
clotting
Disease Defense
Systemic Vessels
Blood = Plasma + Formed (Cellular) Elements
Plasma• ~ 55% blood volume• ~ 92% of plasma is water
• High dissolved oxygen content• Dissolved proteins
• Albumins• Globulins• Fibrinogen
Cells• ~ 45% blood volume• RBCs ~ 99% of cells• WBCs ~1% of cells
• Albumins– 60% of plasma proteins– viscosity
The Proteins in Plasma
• Globulins– 35% of plasma proteins
• Immunoglobulins attack foreign invaders
• Fibrinogen– React in clotting reaction– Form fibrin (serum = plasma - fibrinogen)
Cellular Components• RBCs (erythrocytes)~ 99% of all cells.
• ~ 1/2 blood volume.
Lacks mitochondria,
ribosomes, nuclei
Life span = ~120 days
Hematocrit = % of blood occupied by cellular components (~ RBC volume)
Scanning Electron Micrograph (SEM)
of Erythrocytes or Red Blood Cells (RBCs)
on the tip of a hypodermic needle.
Hemoglobin
Erythropoietin
Life and death of an RBC
Anemia• Pernicious anemia
– Low Fe absorption – Vitamin B12 and instrinsic factor
• Hemorrhagic anemia
• Sickle cell anemia
• Hypochromic anemia
• Hemolytic anemia
• polycythemia
Pernicious anemia
Blood Types - ABO
What type?
What type?
Erythroblastosis fetalis
• Neutrophils– 70% circulating leukocytes– Highly active aggressive phagocytes
• Eosinophils (acidophils)– Much less common– Attracted to foreign compounds reacted with
antibodies– Parasitic infections
• Basophils– Relatively rare– allergeries– Release histamines.
Granular Leukocytes (WBCs)
• Monocytes– Migrate into peripheral tissues
and differential into Macrophages
– Highly mobile phagocytic cells– diapedesis
• Lymphocytes – Primary cell of the lymphatic system
• T-cells attack foreign cells directly• B-cells produce antibodies
Agranular Leukocytes
NeverLet Monkeys Eat Bananas
• Platelet cells (Thrombocytes)– Fragments of Megakaryocytes – enclosed packets of cytoplasm for blood
clotting
Pulmonary circuit - from heart
to lungs
back to heart
Systemic circuit- from heart
to body
back to heart
Arteries = vessels that carry blood away from the heart.
Veins = vessels that return blood to the heart.
Capillaries = smallest vessels, found between smallest arteries
and veins. These are the exchange vessels.
• Myocardium
• Chambers
• Valves(one-way-flow)
• Pericardial Sac
The Heart
Location of the Heart in the Thoracic Cavity
Epicardium– Visceral pericardium
Myocardium– Muscular wall of the heart
Endocardium– Epithelium of inner surface
• Most of the heart is Myocardium
- Contractile Myocardiocytes
* Interconnected by intercalated discs
The Heart is Dual Pump
Position and Orientation of the Heart
Sectional Anatomy of the Heart
RA -> ______ valve -> RV -> _____ valve -> pulmonary trunk -> pulmonary ______s -> lungs -> pulmonary _____s -> LA -> ____ valve -> LV -> ___ valve -> ascending aorta -> aortic arch
Receives blood from systemic circuitSuperior vena cavaInferior vena cava
Coronary veinsReturn blood to coronary sinus then on to right ventricle
Foramen ovale open during embryonic developmentFossa ovalis after birth
Blood Flow through Heart
Right Ventricle
Blood comes from right atrium to right ventricle through the atroventricular (AV) valve
- Pulmonary semilunar valve
Blood leaves Rt Ventricle via pulmonary Semilunar valve to pulmonary trunk.
Branches to left and right pulmonary arteries
- Chordae tendineae- Papillary muscles
Right AV valve / Tricuspid valveThree cusps of fibrous tissue
Valves of the Heart
How do papillary muscles work?
Heart Valves and Heart Sounds
• Placement of a stethoscope varies depending on which heart sounds and valves are of interest.
• Closure of the AV valves create the 1st heart sound (‘lub’).
• Closure of the semilunar valves create the 2nd heart sound (‘dupp’).
Coronary Circulation
Normal Functional Heart Anatomy
Congenital Heart Defects
Congenital Heart Defects
Congenital Heart Defects
The Cardiac Cycle
Recording of the electrical activities in the heart
The Electrocardiogram
P wave = Atrial Depolarization
QRS complex
= Ventricular Depolarization
T wave
= Ventricular Repolarization
ECG
The Conducting System of the Heart
Heart cycle