Physiology Unit 3 Lecture 12: The Cardiovascular System - Blood

what are the functions of blood

transport gases, nutrients, waste products, processed molecules, regulators molecules, regulate pH, maintain body temperature, protect against foreign substances, and clot formation

what are the 3 substances in the composition of blood

blood, plasma, formed elements

blood

connective tissue with liquid matrix containing cells and cell fragments

plasma

the liquid matrix

What percent of blood volume does plasma consume?

55% of blood volume

formed elements

are the cells and cell fragments

What percent of blood volume does the formed elements consume?

45% of blood volume

what is the average total of blood volume in females

4 to 5 L

what is the average total of blood volume in males

5 to 6 L

___ is the liquid matrix of blood

plasma

what is a colloid?

plasma

define colloid

liquid containing suspended substances that don't settle out of solution (mostly plasma proteins)

what makes up plasma? and their percentages

91% water, remainder proteins, ions, nutrients, waste products, gases, regulatory substances

the composition of plasma remains relatively _____ through ____________ even though materials are constantly moving into and out of the blood.

constant
homeostasis mechanisms

list the plasma proteins

albumins, globulins, fibrinogen

albumins

viscosity, osmotic pressure, buffer, transports fatty acids, bilirubin, thyroid hormones

globulins

transports many substances in immunity. alpha, beta, and gamma subtypes

alpha globulin

protects tissue from inflammation damage and transports thyroid hormones and lipids

beta globulin

transports iron, lipids, helps with complement immunity

gamma globulin

involved in immunity with circulating antibodies

fribogen

blood clotting, serum is plasma without clotting factors

ions

involved in osmosis, membrane potentials, and acid base balance

nutrients

glucose, amino acids, triacylglycerol, cholesterol, vitamins

waste products

urea, uric acid, billirubin, lactic acid, creatine, ammonia salts

urea and uric acid is the breakdown product of what

protein metabolism

billirubin is the breakdown product of what

red blood cells

lactic acid is the end product of what

anaerobic respiration

gases

oxygen, carbon dioxide and inert nitrogen

regulatory substances

hormones, enzymes

What are the formed elements with in the blood

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

define hemotopoiesis or hemopoiesis

process of blood cell production

in an infant where does hemopoiesis occur

in yolk sac of embryo, liver, thymus, spleen, lymph nodes, red bone marrow

after birth where does hemopoiesis occur

red bone marrow and lymphatic tissue

stem cells

all formed elements derived from single population of hemocytoblasts

when a hemocytoblast divides, one daughter cell remains a ______ while the other differentiates into either a _________ or a ___________

hemocytoblast
myeloid stem cell
lymphoid stem cell

chemical signals such as __________ help regulate development

colony-stimulating factors (CSF)

erythropoietin (EPO)

a hormone produced by the kidneys that stimulates red blood cell development

myeloid stem cells break down into

proerythroblasts
myeloblasts
monoblasts
megakaryotes

proerythroblasts form

red blood cells

myeloblasts form

basophils
neutrophils
eosinophils

monoblasts form

monocytes

megakaryoblasts form

platelets

lymphoid stem cells become

lymphoblasts

lymphoblasts develop into

lymphocytes (WBCs)

shape of red blood cells

biconcave disc shape

red blood cells diameter

7.5 um

since RBCs have no nucleus they are a

carrying vesicle

describe structure of RBCs

flexible and capable of bending to allow them to pass through small vessels so they can move with the blood flow

what do RBCs contain

hemoglobin, lipids, ATP, carbonic anhydrase

Function of RBC

transport oxygen from lungs to tissue

when oxygen is transported through RBCs ____ percent of oxygen is attached to hemoglobin and ___ percent is dissolved in plasma

98.5% & 1.5%

When CO is transported from tissues to lungs in the RBS _____ percent is dissolved in plasma, _____ percent is in contamination with hemoglobin and _____ percent is transported as bicarbonate ions.

7%
23%
70%

erythropoiesis

formation of red blood cells

How long does erythropoiesis take?

about 4 days

how long does a red blood cell last in circulation? and what happens to it?

110-120 days. then ruptures (hemolysis)

what is the first step of red blood cell production?

hypoxia is detected by the kidneys

in the red blood cell production process, after hypoxia is detected by the kidneys. what happens?

the kidneys increase secretion of erythropoietin (EPO)

in the red blood cell production process, after the kidneys increase secretion of erythropoietin (EPO). what happens

EPO stimulates RBC production in the red bone marrow

in the red blood cell production process, after EPO stimulates RBC production in the red bone marrow. what happens?

as RBCs increase in the blood, the ability to transport O2 increases

If O2 levels rise, less EPO is released and RBC production _________

decreases

Understand the breakdown of hemoglobin

draw out

how many subunits are in hemoglobin

4

globin

a single polypeptide subunit of hemoglobin

list the 3 types of hemoglobin

embryonic, fetal, and adult

describe oxyhemoglobin

iron of hemoglobin bound to oxygen. 4 per molecule of hemoglobin, and have a bright red color

describe deoxyhemoglobin

hemoglobin not bound to oxygen, dark red color, and in the veins

describe carbaminohemoglobin

globin of hemoglobin bound to carbon dioxide

how many hemes are are one globin group

1

list the clinical implications of hemoglobin

poisons, sickle cell disease, cyanotic heart or lung disease

what cell has a nucleus and attract stain in slide preparations

white blood cells

describe granulocytes

have large granules and loved nuclei

Granulocytes include _____________________, _______________________, and ________________________.

neutrophils
eosinophils
basophils

describe agranulocytes

have granules not easily seen under scope

agranulocytes include ________ and _________.

lymphocytes monocytes

WBC function

protect the body from incading microorganisms and remove dead cells and debris from the body

what are the 3 main characteristics that help WBC perform their functions

ameboid movement
diapedesis
chemotaxis

define ameboid movement

directed movement similar to amoeba

define diapedesis

cells leave blood stream by becoming thin, elongating and moving either between or through endothelial cells of capillaries

define chemotaxis

attraction to and movement toward foreign materials or damaged cells. accumulation of dead white cells and bacteria is pus

what surfaces glycoproteins and proteins allow adhesion to other molecules such as collagen

platelets

what contains circumferential band of microtubules that help support shape

platelets

what has contractile proteins attached to the cytoskeleton that allows for the ability to swell, change shape, or contract

platelets

what is important in preventing blood loss

platelets

hemostasis

arrest or stoppage of bleeding

what is hemostatic balance

the dynamic balance between blood clot formation (coagulation) and blood clot dissolution (fibrinolysis)

a thrombus leads to what

a decrease or complete. arrest of blood flow

what events prevent excessive blood loss

vascular spasm, platelet plug formation, coagulation

define vascular spasm

(first step) vasoconstriction of damaged blood vesels. can occlude small vessels. caused by thromboxanes from platelets and endothelin from damaged endothelial cells

platelet plug compares what?

primary hemostasis vs secondary hemostasis

primary hemostasis is achieved when

the platelet plug completely occludes the vessel and stops blood flow

secondary hemostasis is achieved when

the activated platelet expresses chemical factors on its surface that help initiate coagulation cascade

what are the steps of the plate let plug

platelet adhesion, platelet activation, platelet aggregation

describe the first step of the platelet plug: platelet adhesion

platelets circulate in the blood but are prevented from binding to wall by anti platelet factors. when damage occurs collagen is exposed and von Willebrand factor is released as a glue that promotes platelet adhesion to the area of injury

describe the first step of the platelet plug: platelet activation

platelets adhere to the damaged vascular wall. activation causes platelets to change shape

describe the first step of the platelet plug: platelet aggregation

final step. activated platelets have a high concentration of receptors that bind with great affinity to fibrogen allowing for the rapid formation of an occlusive platelet thrombus. whole process occurs within 10 minutes

define coagulation

a highly regulated series of steps resulting in the formation of fibrin that provides the framework for the loose platelet plug.

coagulatory proteins are activated through ________.

extrinsic and intrinsic pathways

the common pathway results in the creation of

thrombin

what is thrombin responsible for?

the conversion of fibrogen to fibrin

fibrin forms what

the meshwork holding the new clot together