cardiovascular system

The Blood

Functions and Properties of Blood

 Blood is a liquid connective tissue consisting of cells surrounded by a liquid matrix (plasma).

-          Plasma 55%

-          Red blood cell 45%

-          Buffy coat, components of (white blood cells and plasma

-          The cellular components (formed elements) of blood include red blood cells, white blood cells and platelets.

-           The plasma portion of blood consists of water, proteins and other solutes.

-         The amount of blood is depends on the size of the person and then the amount of adipose tissue. Also its depends on concentration of ions.

-         Female has less blood compare than male

-         Blood transports oxygen, carbon dioxide, nutrients, hormones, heat and waste products.

-          Blood regulates homeostasis of all body fluids, pH, body temperature and water content of cells.

-         Blood protects against excessive loss by clotting and against infections through the use of white blood cells.

Formation of Blood Cells

-          Lymphocytes are able to live for years while most other blood cells live for hours, days, or weeks.

-          The number of red blood cells and platelets remains rather steady while that of white blood cells varies depending on invading pathogens and other foreign antigens.

-           red blood cell and platelets is constant, wbc nag babago bago depends on the  presence of pathogens or disease causing agent inside the body.

-        The process of producing blood cells is hemopoiesis (hematopoiesis). Pluripotent stem cells differentiate into each of the different types of blood cells.

-          Differentiation means from unspecialized cell to specialize cell

-        Pluripotent stem cell precourcer ng blood natin

-        It will develop into myeloid and lymphoid stem cell.

Red Blood Cells

·         Red blood cells (erythrocytes) contain the protein hemoglobin that is used to carry oxygen to all cells and to carry 23% of total carbon dioxide to the lungs.

·         Make up about 99% of the blood cellular component 

·         As RBC matures it will lose their nucleus

·         Anemia- low blood cell count

·         Hemoglobin is a protein that is responsible to carry oxygen. Responsible for red pigmentation of RBC

·         There different hemoglobin that is found in RBC

-          Oxyhemoglobin – carry oxygen and bright red

-          Deoxyhemoglobin- does not carry oxygen, darker red, it carry carbon dioxide

-          Also called carboxyhemoglobin

·         Each hemoglobin molecule contains an iron ion which allows each molecule to bind four oxygen molecules.

·         Red blood cells have no nucleus or other organelles and are biconcave discs. The lack of a nucleus and the shape allow the cells to efficiently carry oxygen.

·         The form or shape of each cell corresponds to each function\

·         Hemoglobin is also involved in regulating blood flow and blood pressure via the release of nitric oxide which causes vasodilation that improves blood flow and enhances oxygen delivery.

·        Red blood cells also contain carbonic anhydrase which catalyzes the conversion of carbon dioxide and water to carbonic acid. This compound transports about 70% oс carbon dioxide in the plasma. It is also a buffer.

·       Red blood cells live for only about 120 days. Dead cells are removed from the circulation by the spleen and liver.

·       Breakdown products from the cells are recycled and reused.

·       Erythropoiesis (production of red blood cells) begins in the red bone marrow. Reticulocytes (immature red blood cells) enter the circulation and mature in 1 to 2 days.

·       If it is still reticulocytes pa lang siya it still have nucleus but if it’s mature for 1 to 2 days it will lose nucleus

·        Erythropoietin, a hormone released by the kidneys in response to hypoxia (lowered oxygen concentration) stimulates differentiation of hematopoietic stem cells into erythrocytes.

Erythropoietin

-         Production of RBC

-         Hormones that produce by the kidney

Proerythroblasts 

-         It is found on Red bone marrow

-         Precoursercell para maka pag produce ng RBC

White blood cell

• White blood cells (leukocytes) contain a nucleus and organelles, but no hemoglobin.

·         Leukocytes are classified as either granular (containing vesicles that appear when the cells are stained) or agranular (containing no granules).

·         Granular leukocytes: neutrophils,

eosinophils, basophils

-          Granular – contain vesicles that appear when the cells are stained

·         Agranular leukocytes: lymphocytes, monocytes

-          Agranular- contain no granules

·         White blood cells may live for several months or years. Their main function is to combat invading microbes.

·        During an invasion, many white blood cells are able to leave the bloodstream and collect at sites of invasion. The process is called emigration (diapedesis)

·       In general, an elevation in the white blood count usually indicates an infection or inflammation.

·       A low white blood cell count may develop due to several causes.

·       A differential white blood cell count will help to determine if a problem exists..

Neutrophil-to destroy bacteria,virus into blood stream, main function is for phagocytosis 

Lymphocytes- to provide immunity for the body

Monocytes- is to destroy bacteria, virus in the blood

Eosinophils- to get rid of parasythetic? Infection like worm infection.

Basophil- to control inflammation and allergic reaction.

Platelets

·         Platelets are used to clot the blood.

·         Under the influence of the hormone thrombopoietin, hemopoietic stem cells differentiate into platelets.

·         Thrombopoietin- enzyme that will activate the platelets

·         hemopoietic stem cells- precoursorcell of our platelet, difeerentiate pag ng mature na

·         Megakaryocytes in red bone marrow splinter into 2000-3000 fragments to create the platelets that contain many vesicles but no nucleus.

·       Platelets survive for only 5 to 9 days.

Stem Cell Transplants from Bone Marrow and Cord Blood

·         Bone marrow transplants are performed to replace cancerous red bone marrow with normal red bone marrow. The donor's marrow is usually collected from the iliac crest of the hip bone.

·       Stem cells collected from an umbilical cord after birth are frozen and may also be used and have advantages over bone marrow transplants.

Hemostasis

Hemostasis means to stop bleeding.

The process involves:

·         Vascular spasm

·         Platelet plug formation

·       Blood clotting (coagulation)

-          Blood clotting involves several clotting (coagulation) factors identified by Roman numerals and divided into three stages.

-         The three stages are the extrinsic pathway, intrinsic pathway and common pathway.

-         Yung broken cells natin will release chemical that will stimulate the production of ? maactivate platelets para ma coagulate yung blood clot, then titigil na yung pag dugo,

-         Once the clot forms, it consolidates (tightens) to pull the edges of the damaged vessel together.

-         Vitamin K is needed for normal clot formation although it is not directly involved. It is used in the synthesis of 4 clotting factors.

-         Small, unwanted clots are usually dissolved by plasmin (fibrinolysin).

Components of plasma

Plasma is liquid portion of blood that compose of water, proteinS

Different protein that can be found in plasma

Albumin- smallest plasma protein, and to pull water in maintaining blood pressure

Globulin- to transfort lipids,  fats, soluble vatamins

Fibrinogen- is the protein that is needed for blood clotting

Blood Groups and Blood Types

-          Blood is characterized into different blood groups based on the presence or absence of glycoprotein and glycolipid antigens (agglutinogens) on the surface of red blood cells.

-          There are 24 blood groups and more than 100 antigens Because these antigens are genetically controlled, blood types vary among different populations.

-          Classification is based on antigens labeled A, B or AB with O being the absence of the antigens.

-          An additional antigen, Rh, is present in 85% of humans.

-          Antigen – produce by pathogens

-          Antibody- produce by body to combat antigens

-          Blood plasma usually contains antibodies (agglutinins) that react with A or B antigens. An individual will not have agglutinins against his or her own blood type.

-          In order to determine a person's blood type, typing and cross-matching are performed.

-          A drop of blood is mixed with an antiserum that will agglutinate blood cells that possess agglutinogens that react with it.

Hemolytic Disease of the Newborn

-          At birth, small amounts of fetal blood leak into the maternal circulation. If the baby is Rh+ and the mother is Rh-, she will develop antibodies to the Rh factor.

-          During her next pregnancy with an Rh+ baby, when she transfers antibodies to the fetus (a normal occurrence), transferred anti Rh antibodies will attack some of the fetus' red blood cells causing agglutination and hemolysis.

Disorders: Homeostatic Imbalances

-          Sickle cell disease is a genetic anemia (oxygen-carrying capacity of the blood is reduced).

-          The red blood cells of individuals with this disease contain hemoglobin-S (Hb-S) that causes red blood cells to bend into a sickle shape when it gives up oxygen to the interstitial fluid.

THE CARDIOVASCULAR SYSTEM

-          A closed system of the blood, heart and blood vessels The blood transports the materials

-          The heart pumps blood

-          Blood vessels allow blood to circulate to all parts of the body

-          The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

-          For the circulation of blood, the one that transport the materials

-          Function of CVS is to deliver nutrients and oxygen and to remove carbon dioxide and other waste products

-          Heart is the one that pumps the blood

The Heart

Location :

·         Thorax between the lungs

·         Pointed apex directed toward left hip

·         About the size of your fist Less than 1 lb.

The Heart: Coverings

·         Pericardium a double serous membrane

-          Visceral pericardium

-          Next to heart , before the muscle of heart

-          Parietal pericardium

-          Outside layer

·         Serous fluid fills the space between the layers of pericardium

The Heart: Heart Wall

·         Pericardium- membrane enclosing the heart

-consists of an outer fibrous layer

 -inner double layer of serous membrane.

·         Epicardium

 -Outside layer

-This layer is the parietal pericardium

- Connective tissue layer

·         Myocardium - Middle layer

-           Mostly cardiac muscle

-          Function involuntary

·         Endocardium - Inner layer

-           Endothelium

The Heart: Chambers

Right and left side act as separate pumps

 Four chambers

1. Atria

- Receiving chambers , receive blood

- Right atrium

- Left atrium

2. Ventricles

- Discharging chambers, discharge blood

- Right ventricle

-Leftventricle

The Heart: Valves

Allow blood to flow in only one direction

 Four valves

 1. Atrioventricular valves- between atria and ventricles

- Bicuspid valve (left)

- Tricuspid valve (right)

2. Semilunar valves - between ventricle and artery

- Pulmonary semilunar valve

- Aortic semilunar valve

The Heart: Associated Great Vessels

1. Aorta - Leaves left ventricle

2. Pulmonary arteries -  Leave right ventricle

3. Vena cava - Superior and inferior

- Enters right atrium

4. Pulmonary veins - Enter left atrium

Blood Vessels: The Vascular System

Taking blood to the tissues and back

·         Arteries- Carries oxygenated blood

-          Carries Blood away heart

·         Veins-  Carries deoxygenated blood

-          Carries  Blood to heart

·         Capillaries -Oxygen, nutrients, and wastes are exchanged between the blood and the tissues

·         Arterioles- small arteries

·         Venules – small veins

Blood Vessels: Anatomy

 Three layers (tunics)

·         Tunic intima/interna

-          Endothelium

·         Tunic media - Smooth muscle

-          Controlled by sympathetic nervous system

·         Tunic externa - Mostly fibrous connective tissue

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

Pulse

·         Pulse - pressure wave of blood

·         Monitored at "pressure points" where pulse is easily palpated

Blood Pressure

Force of the blood inserted at the walls of blood vessels

 1 Systolic-occurs when the heart contracts to pump blood out

2 Diastolic - occurs where the heart relaxes after contraction

·         Pressure in blood vessels decreases as the distance away from the heart increases

·         Normal: 120/80 - 140/90 mmHg

·         millimeter of mercury (m

Cardiovascular System Disease

·        Arteriosclerosis- buildup of fat deposit and other substances on the wall of the arteries

·         Heart Failure- inability to pump enough blood to meet the body’s energy demands

·         Aneurysm- bulge or bubble in the wall of artery

·         Stroke- damaged to blood vessels supplying the brain. Due to blockage or rupture.

·         Luekemia, cancer of the blood- cell divided into uncontrolled manner.

-          Due to virus or genetic mutation