Blood

cardiovascular system consists of

heart, blood vessels, blood

pump

heart

conducting hoses

blood vessels

fluid connective tissue

blood

blood

a specialized connective tissue that contains cells suspended in a fluid matrix

characteristics of blood

38* C (100.4 F) is normal, High viscosity (5x thicker than water), Slightly alkaline - pH 7.4

Blood volume (liters)

7% of body weight (kilograms)

75kg person would have

5.25 liters of blood

functions of blood

transportation, regulation, restriction, defense, stabilization

blood transports

dissolved gases, nutrients, hormones, and metabolic wastes

blood regulates

pH and ion composition of interstitial fluids

blood restricts

fluid loss at injury sites

blood defends against

toxins and pathogens

blood stabilizes

body temperature

2 components of whole blood

plasma and formed elements

plasma

Fluid portion of blood

formed elements

cells and cell fragments

fractionation

process of separating whole blood for clinical analysis into plasma and formed elements

plasma makes up

55% of blood

more than 90% of plasma

water

plasma contains

dissolved proteins

water, ions, and small solutes

what materials in plasma and interstitial fluid exchange across capillary walls?

plasma proteins

fibrinogen, albumin, globulin

Fibrinogen

4% of plasma proteins; produced by liver; forms fibrin threads of blood clot

Fibrinogen is converted into \_____

fibrin (insoluble form)

Conversion of fibrinogen to fibrin

is the final step of a clotting process that involves multiple clotting factors

serum

plasma without clotting factors

other plasma proteins (1 percent)

varying concentrations of enzymes and hormones

Origins of Plasma Proteins

90% made in the liver, antibodies made by plasma cells, peptide hormones made by endocrine organs

albumins, globulins, fibrinogen

plasma proteins

formed elements of blood

red blood cells (erythrocytes), white blood cells (leukocytes), platelets

hemopoiesis

process of producing formed elements

what are platelets?

small, membrane-bound cell fragments that contain enzymes and other substances important to clotting

what are white blood cells?

White blood cells are involved in protecting the body against both infectious disease and foreign invaders

five types of leukocytes

neutrophils, eosinophils, basophils, lymphocytes, monocytes

red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

most blood cells are

red blood cells

red blood cells make up

99.9% of blood's formed elements

red blood cells contain

hemoglobin

hemoglobin

red pigment of red blood cells

function of hemoglobin

In red blood cells, carries oxygen from the lungs to body's tissues and returns carbon dioxide from tissues back to lungs. It also maintains the shape of red blood cells.

red blood cell count

the number of RBCs in 1 microliter of whole blood

red blood cell count in adult male

4.5-6.3 million

red blood cell count in adult female

4.2-5.5 million

hematocrit

packed cell volume

Hematocrit percentage in females

42%

hematocrit percentage in males

46%

what does not lead to a decrease of hematocrit?

dehydration

structure of red blood cells

Small and highly specialized discs, Biconcave discs, Thin in middle and thicker at edge

Important effects of RBC structure on function

Large surface area to volume ratio, Quickly absorb and release oxygen, Form stacks called rouleaux, Smooth blood flow through narrow blood vessels, Bend and flex when entering small capillaries

mature red blood cells

Anucleate (lack nuclei), Lack mitochondria and ribosomes, Unable to divide, synthesize proteins, or repair damage, Live about 120 days

RBC formation and turnover

1% of circulating RBCs wear out per day, About 3 million RBCs per second

hemoglobin

protein in RBC, carries oxygen

hemoglobin in adult male

13-18 g/dL

hemoglobin in adult female

12-16 g/dL

fetal hemoglobin

Form of hemoglobin in embryo or fetus, Binds oxygen more readily than does adult hemoglobin, Takes up oxygen from maternal blood at placenta

hemoglobin structure

4 subunits, quarternary structure

four globular protein subunits

Each with one molecule of heme, Each heme contains one iron ion

Each heme contains

one iron ion

iron interacts with oxygen to form

oxyhemoglobin (HbO2)

each rbc contains about

280 million hemoglobin molecules

Each RBC can carry

over a billion O2 molecules

Peripheral capillaries

oxygen leaves the blood in exchange for CO2

oxygen in peripheral tissues

low

hemoglobin in lungs

binds to oxygen, becoming oxyhemoglobin and then oxygenated RBCs transported to the body's tissues, where oxyhemoglobin releases oxygen and picks up carbon dioxide, becoming carbhemoglobin

Anemia

A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume.

what does not lead to a decrease in hematocrit?

dehydration

Erythropoiesis

red blood cell formation

embryonic blood cells move from bloodstream

to liver, spleen, thymus, bone marrow

stem cells

unspecialized cells that are able to renew themselves for long periods of time by cell division

stem cells produce

red blood cells, white blood cells, platelets

Erythropoiesis in adults

occurs only in myeloid tissue (red bone marrow)

Hemocytoblast

stem cells that give rise to all the formed elements of the blood

myeloid stem cells

become RBCs, some WBCs

lymphoid stem cells

become lymphocytes

hematologists

blood specialists

Stages of red blood cell formation

hemocytoblast, rubriblasts, reticulocyte,erythrocyte

Erythropoietin

hormone that stimulates the production of RBCs

Erythropoietin secretion

The kidney is responsible for stimulating red blood cell production through: A. erythropoietin secretion., B. gluconeogenesis., C. renin secretion., D. vitamin D activation.

blood doping

A dangerous practice used by some athletes, Re-infuse packed RBCs to elevate hematocrit

Hemoglobin Recycling

Macrophages of spleen, liver, and red bone marrow, Engulf aged RBCs, Remove Hb molecules from hemolyzed (ruptured) RBCs, Break Hb into components, Only the iron of each heme unit is recycled

hemoglobinuria

red or brown urine, due to abnormally high hemolysis in bloodstream

hematuria

whole RBCs in urine due to kidney or tissue damage

iron is removed from each heme unit forming

green biliverdin, converted to orange-yellow bilirubin, bilirubin is excreted by liver in bile

Jaundice is caused by

buildup of bilirubin in the blood

urobilins and stercobilins

produced from bilirubin by bacteria and oxygenation

iron recycling

Iron removed from heme leaving biliverdin, To transport proteins (transferrin) , To storage proteins (ferritin and hemosiderin)

surface antigens

Substances on plasma membranes that identify cells to immune system. Normal cells are ignored and foreign cells are attacked.

blood type

Determined by presence or absence of surface antigens on RBCs: A, B, and Rh (or D)

four blood types

Type A (surface antigen A), Type B (surface antigen B), Type AB (antigens A and B), Type O (neither A nor B)

Rh blood group

based on presence or absence of Rh antigen

Rh positive (Rh+)

presence of Rh antigens on the RBC membranes

Rh negative

Rh antigen is absent

Agglutinogens

surface antigens on RBCs, screened by immune system

agglutinins

Antibodies in plasma, Attack antigens on foreign RBCs (Causing agglutination (clumping) of foreign cells)

type a blood

anti-B antibodies

type b blood

anti-A antibodies

type o blood

both anti-A and anti-B antibodies

Type AB blood

A and B antigens, no antibodies

cross reaction

May occur in a transfusion of blood or plasma from one person to another. Occurs if donor and recipient blood types are not compatible. Plasma antibody meets its specific surface antigen (RBCs agglutinate and may hemolyze)