Transcript Heart & Blood Vessels

Blood
Functions of Blood
Transports: oxygen from the lungs to parts
of the body, Carbon dioxide from body to
lungs
 Carries nutrients, ions and water from the
digestive tract to all cells of the body
 Regulates body temperature, pH
 Protection – clotting, immunity
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The Blood
Blood cell type
Blood cells make up
about 45% of blood
55% is plasma
8% of body weight is
blood
5-6 litters for humans
How blood cells are formedHematopoiesis
They’re produced in red bone marrow
 They develop from undifferentiated
mesenchyma cells, called stem cells or
hematocytoblasts.
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Components of blood
Erythrocytes – Red Blood Cells (RBC)
 Leukocytes – White Blood Cells (WBC)
 Thrombocytes – platelets – fragments with
clotting, Disk shaped, no nucleus, Lives 5
to 9 days
 Plasma – 55%, liquid, contains dissolved
substances
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Anatomy of Erythrocytes
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Erythrocytes-red blood cells that are biconcave. It
contains hemoglobin (280 million molecules) ( Hemetakes oxygen to the cell) ( Globin- takes carbon dioxide
from the cell)
Non iron – converted to bilirubin – yellow, jaundice
Red pigment lasts 120 days, Erythropoiesis
Leukocytes-white blood cells
Granular
Eosinophils- combat irritants such as:
pollen, or cat hair, antihistamine
 Basophils- involved in allergic reactions,
they release heparin, histamine, and
serotonin.
 Neutrophils-most common, move into
tissues where they phagocytize foreign
substances, and secrete the enzyme
lysozyme which destroys bacteria
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Leukocytes-white blood cells
Agranular
Lymphocytes – T and B (antibodies)
 Monocytes – Macrophage breakdown
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Plasma
Albumins – 58 %, proteins maintain water
balance between blood and tissue
 Globulins -38%, (antibodies)
 Fibrogen – 4% blood clotting
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Clotting Mechanism - Thrombosis
Damage to blood vessel contracts, vascular spasm
The roughened surface causes platelets to clump
together and stick to surface
Prothrombin, a plasma protein, is converted into
thrombin.
Soluble fibrinogen converts into insoluble fibrin.
Fibrin forms long threads that act like a fish
net. The fibrin tightens (syneresis)
Serum – clear yellowish liquid after clot forms
Blood Types
Allele from
Parent 1
Allele from
Parent 2
Genotype of
offspring
Blood types of
offspring
A
A
AA
A
A
B
AB*
AB
A
O
AO
A
B
A
AB*
AB
B
B
BB
B
B
O
BO
B
O
O
OO
O
The different Blood Groups
Type A
Only A
Antigen A
Antibody B
Type B
Only B
Antigen B
Antibody A
Type AB
Both A&B
Antigen
A&B
None
Type O
Neither A
or B
None
Both
Antibodies
Principles of the ABO Blood group
compatibility
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The ABO blood group consists of those
individuals who have the presence or absence of
two major antigens. The RBC membrane,
Antigen A and Antigen B.
Agglutination – reaction between antigen and
antibody, causing clumping of RBC’s
Type O blood – universal donor, no antigens
Type AB – universal recipient
RH – (+ or -), Protein identified in Rhesus
monkey, Erythroblastosis fetalis – hemolytic
disease
The HEART -thoracic Cavity
Between lungs,
obliquely with most to
the left side, cone
shaped, closed fist,
inside pericardial sac
 Cardiology – study of
the heart
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Layers of the Heart Wall
Heart Wall Layers
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Pericardium – parietal part
around heart
Epicardium-visceral part, thinserous tissue, on heart surface
Myocardium-cardiac muscle,
intercalated disc, gap junctions
Endocardium- endothelium,
inner most lining
The Chambers and valves
Atria - Upper chambers of the heart ,Divided
into left atrium & right atrium, Separated by
the interatrial septum, both have thin,
flexible walls
 Ventricles - Lower chambers of the heart,
Separated by the interventricular septum,
more muscle, greater pumping power
needed
 Valves – prevent back flow.
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Flow of blood through heart
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Vena cava
R. Atrium
Tricuspid valve
R. Ventricle
Pulmonary Semi
lunar valve
Pulmonary artery
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Septum
Lungs
Pulmonary Vein
L. Atrium
Bicuspid (Mitral) valve
L. Ventricle
Aortic semi lunar
Conduction System – stimulates
contraction
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Sinoatrial (SA) node – “pacemaker” starts
& sets heart rate (modified by autonomic
system) Impulse spreads over atria
causing contraction. Depolarize the
atrioventricular (AV) node. Bundle of His
runs in interventricular septum & around
ventricle (bundle branch) to Purkinje fibers
that contract ventricles.
Cardiac Cycle – 1 heart beat
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Systole-contract: top
number in B.P.
– 1 second
 Artia contract
 Ventricle relax
 “Lub” cuspid (AV)
valves
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Diastole-Relax:
bottom number in B.P.
– 4 seconds
 Heart relaxes
– 3 seconds
 Artia relax
 Ventricle contact
 “Dub” semiHeart
lunarrate
valve
average : 72 beats/minute
Average blood pressure 120 / 80 using Sphygmomanometer
Other terms
Electrocardiogram – electrical changes
that accompany the heart beat
 Fibrillation – disturb action potential on
heart, cessation of an effective heartbeat
 Stroke volume – amount of blood ejected
by the left ventricle
 Cardiac output – Stroke volume (70 ml
aver.) X Pulse (beats per minute)
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BLOOD VESSELS:
Vein, Artery, & Capillary
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Artery/Arterioles
– Thicker, stronger (more muscle), 3 coats around
hollow center (lumen), Elasticity, Contractility
Capillary
– 1 cell thick, microscopic, diffusion, pass single file
Vein/Venules
– Less tissue (tunica media), 3 coats, walls of smallest
do not contain smooth muscle, valves, blood to heart
Histology of vessels
Major Vessels
Superior (anterior) Vena Cava – blood into
R. atrium from head / arms
 Inferior (posterior) Vena Cava – blood into
R. atrium from body / legs
 Great saphenous vein – longest vein, legs
 Coronary sinus – blood from heart
 Coronary arteries – blood supply to heart
 Ascending aorta - to body
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Major Blood Circulatory Routes
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Systemic-L. Ventricle-Aorta-Arteries-ArteriolesCapillaries-Venules-Veins-Vena Cava
Coronary-myocardium of heart
Hepatic-liver intestines
Pulmonary-R. Ventricle-Pulmonary Artery (blue)Lungs-Pulmonary Vein (red) -L. Atrium
Cerebral-brain
Fetal- temporary route between fetus & mother
Other vessels terms
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Vasoconstriction – muscle constriction, decrease
lumen size
Vasodilatation – increase lumen size
Normal blood volume – 5 Liters
Pulse – expansion and recoil of an artery with
each contraction
Venous return – pumping action of heart /
velocity of blood flow (peripheral resistance),
skeletal muscle contractions, valves, breathing
Conditions / disorders of blood
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Hemophilia – inherited expression on X chromosome,
lack clotting factors
Leukemia – cancer of white blood cells
Hemolytic anemia – RBC rupture faster than normal rate
Iron defiency anemia – excessive iron loss; lower RBC
production
Septicemia – blood poisoning
Embolism – clot lodge in a vessel, obstructing blood flow
Mononucleosis – Epstein – Barr virus; sore throat, lymph
nodes swollen
Conditions / disorders of heart and
vessels
Pericarditis – inflammation of pericardium
 Congenital heart – heart not developed
properly at birth
 Rheumatic heart – untreated strep
infection
 Heart failure – weakening of myocardium,
failure to pump blood
 Coronary artery – reduced blood flow in
arteries to myocardium
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Conditions / disorders of heart and
vessels con’t
Angina pectoris – pain in chest, left arm
and shoulder (reduced blood flow)
 Infarction – death due to interrupted
blood flow (myocardium – heart attack)
 Atherosclerosis – plaque (cholesterol)
masses inside of arterial wall
 Hypertension – high blood pressure
 Varicose vein / hemorrhoids – leaky valves
over stretched vein walls.
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