Chapter 17: Blood
How does the dying red blood cell become split?
Heme is split from globin: -Globin broken down to amino acids (building blocks of protein) -the iron from the heme is salvaged -remaining heme is broken down to bilirubin, which is secreted in bile to the intestine for removal from body
What is the name of the protein found in erythrocytes that transports respiratory gases and provides the red color?
Hemoglobin Other than water, hemoglobin 97% of an erythrocyte. It can bind both oxygen and carbon dioxide.
Vasodilation
Increase in diameter of the blood vessels, especially dilation of arterioles leading to increased blood flow to a part of the body. Helps with cooling the body
Thalassemia
Inherited defect in the ability to produce hemoglobin, usually seen in persons of Mediterranean background.
Of the formed elements what is the only complete cell?
Leucocytes
What is hematocrit (Hct)?
is the % of erythrocytes in whole blood.
Erythropoietin is produced by
kidneys when kidney cells become hypoxic
Renal anemia
lack of EPO kidneys don't produce enough EPO relates to renal disease treatment synthetic EPO
Pernicous anemia
lack of vitamin B12 without b12 RBC only enlarge but do not redivide resulting in large macrocytes
What is the buffy coat composed of?
leukocytes and platelets 1%
Leukocyte Disorders
leukopenia and leukemia
What leukocytes are granulocytes?
neutrophils, eosinophils, basophils
Never Let Monkeys Eat Bananas
neutrophils, lymphocytes, monocytes, eosinophils, basophils
Circulating platelets are kept inactive and mobile by
nitric oxide (NO) and prostacyclin
What is a leucocyte?
white blood cell
Procoagulants (clotting factors)
usually produced by the liver; are present in plasma (mostly plasma protein) Activate one factor and it will activate the next to form a reaction cascade
Thromboembolic disorders
Results from conditions that cause undesirable clot formation, such as roughing of vessel endothelium, slow-flowing blood or blood stasis
How do platelets enter the blood?
When a megakaryocytic sends cytoplasmic extensions through a sinusoid wall, rupture an release the platelets
Which part of the hemoglobin molecule binds carbon dioxide for transport?
amino acids of the globin The heme groups and iron ions are binding points for oxygen, while carbon dioxide binds to and is carried by the globin polypeptides. The combined form is called carbaminohemoglobin. Heme bears an atom of iron that can combine reversibly with one molecule of oxygen.
infectious mononucleosis (kissing disease) (mono)
an infection caused by the Epstein-Barr virus (EBV), characterized by excessive numbers go agranulocytes (no granules) -involove lymphocytes that become enlarged -highly Contagious -usually seen in young adults symptoms: sore throat, redding or swollen tonsils and swelling of lymph nodes
Blood doping (Polycythemia)
athletes remove, store, and reinfuse RBCs before an event to increase O2 levels for stamina
respiratory burst
bacterial killing by generating hydrogen peroxide and hypochlorous acid (bleach)
Hematopoiesis
blood cell formation that occurs in red bone marrow
Coagulation
blood clotting- multistep process where blood is transformed from liquid to a gel. - reinforces platelet plug with fibrin thread. - blood clots are effective for sealing larger vessel breaks -blood is transferred from liquid to gel
B lymphocytes
give rise to to plasma cells, which produce antibodies
Leukemia
-cancerous conditions in which clones of a single WBC remain unspecialized and divide out of control, very fast -without treatment all leukemias can be fatal -death is usually from internal hemorrhage or infections WBC can't do their job) Treatment: irradiation, antileukemic drugs; stem cell transplants -begins in stem cells in bone marrow
phase one of coagulation
-cascade of event Contact activation pathway Intrinsic pathway (things inside blood; our focus) or extrinsic pathway
Platelet plug formation
-chemical released from collagen fibers, changes platelets shape become sticky and spiky, THEY BECOME ACTIVATE, adhering to each other and damaged vessel wall. -once platelets adhere to the site of injury, ADP is released by granules and it creates a positive feedback loop for clot formation *This is the end for small vessel tears
3 phases of clotting
-formation of prothrombin activator -conversion of prothrombin to thrombin -formation of fibrin mesh from fibrinogen in the plasma
What are some dietary requirements for erythrocyte formation?
-iron -B12 -Folic acid -protein, lipids and carbs
Protection functions of the blood include
-preventing blood loss platelets -preventing infection
chronic leukemia
-proliferation of later cell stages. Predominant cell is mature but does not function normally most common in older people
acute leukemia
-quickly advancing because it derives from stem cells appears suddenly, progresses rapidly -primarily affects children, but can be teens
What are the three steps in hemostasis
1. vascular spasm 2. platelet plug formation 3. coagulation (blood clotting)
Blood cells life span
100- 120 days due to lack or nuclei and organelles
What is the normal range of Hemoglobin in the blood?
13-18g/100ml in males 12-16g/100ml in females
How long does the hematopoietic process take?
15 days. This is when the Reticulocytes enters the blood stream
What is the normal blood volume in females?
4-5 liters
What is hematocrit in females?
42% +/- 5%
What is hematocrit in males?
47% +/- 5%
What is the normal blood volume in males
5-6 liters
Plasma makes up ___% of blood
55
What is the pH of blood?
7.35-7.45 (slightly basic)
What is the size of erythrocytes?
7.5 micrometers
Blood makes up ___% of body weight
8
______% of plasma solutes are proteins
8
What is the normal number of WBC in a persons body?
<11,000 WBC per uL, if there is an infection this number will be higher
Anemia
A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume.
What erythrocyte production disorder results from an autoimmune disease associated with insufficient vitamin B12 absorption (step 6)?
A glycoprotein called intrinsic factor, produced by the stomach, is required to absorb adequate vitamin B12. Pernicious anemia results when the stomach does not produce adequate intrinsic factor, often because the cells that produce it are attacked by the body's immune system.
Granulocytes
A group of leukocytes containing granules in their cytoplasm; neutrophils, eosinophils, basophils.
Agranulocytes
A group of leukocytes without visibly staining granules in their nuclei; lymphocytes, monocytes.
Lymphocytes
A type of white blood cell that make antibodies to fight off infections. These can b efound throughout the body, few in blood. 2 different types. -25% of all WBC -circle Nucleus -NO Granules
What is the living component in blood?
Formed elements -erythrocytes, leucocytes and platelets
How does blood prevent the body from blood loss?
-by clotting -platelets and plasma proteins initiate clot formation which aid in halting blood loss
Basophils
-0.5-1% -least abundant -release histamine to promote inflammation that acts like a vasodilator -contains heparin bilobed necleus very hard to see -large purple Granules -Larger than RBC
Eosinophils
-2-4% - attacks parasitic worms, in loose connective tissue, by releasing enzymes that digest their surfaces -have a role in asthma and allergy -Bilobed nucleus -RED Granules -larger than RBC
Monocyte
-3-8% -actively phagocytotic macrophages as they enter tissues, activate lymphocytes -U shaped neucli -Largest cell
Neutrophils
-50%-70% -Most abundant -"Bacteria slayers" -Phagocytic and tend to self-destruct as they destroy foreign invaders, limiting their life span to a few days. -chemically attracted to inflammation -Multi-lobed nuclei -granules -twice as big as RBC
What are the main causes of anemias?
-Blood loss: hemorrhagic anemia -Not enough RBC produced -Too many RBC destroyed
What are some symptoms of hypoxia?
-Blue finger tips - hard time breathing -unconscious
Transport functions of the blood include
-Delivering O2 (oxygen)from the lungs and nutrients from the digestive tract to all body cells -Transporting metabolic wastes from cells to the elimination sites lungs (carbon dioxide) and kidneys (nitrogenous wastes) -Transporting hormones from endocrine organs to target organs
What gives blood the red color?
-Hemoglobin heme pigment bonded to each protein globin chain
What are 3 structural features of an Erythrocyte that make for efficient gas transport?
-Hemoglobin (used to transport O2) makes up 97% of cell volume not counting water -RBCs have no mitochondria (they produce ATP which uses O2) -RBC are dedicated to respiratory gas transport -Hemoglobin binds reversible with oxygen. (Hb carries then releases oxygen)
anemia (not enough RBCs being produced)
-Iron-deficiency -Pernicious anemia (lack of B12) -renal anemia (low EPO) Aplastic anemia (destruction of red bone marrow)
Leukopenia
Abnormally low white blood cell count -possibly due to drugs like glucocorticoids or anticancer drugs
Sickle cell anemia is prevalent in
African-Americans of the Malarial belt and their descendants
What is hemoglobin?
An iron-containing protein on the erythrocyte that carries oxygen and carbon dioxide
What are Erythrocyte disorders classified as?
Anemia or polycythemia
What enzyme removes unneeded clots after healing has occurred?
As healing progresses, the clot retraction process reduces the size of the clot, while plasminogen is activated into plasmin that digests the fibrin in the clot.
Reticulocyte count
Assessment of bone marrow function
How is (dark red) deoxyhemoglobin formed?
At body tissues, oxygen detaches from iron.
How many oxygen molecules can be transported by one hemoglobin molecule?
Four Each iron atom on a heme group can bind reversibly with one oxygen molecule
Instead of dividing, ________ _______ are continuously replaced by _____ _____ located in the red bone marrow.
Blood cells; stem cells
How do blood vessels help control human body temperatures?
Blood vessels have the ability to dilate and constrict to control body temperatre. When body temperature is too low, the tiny blood vessels near the surface of the skin (capillaries) constrict (vasoconscriction). This decreases the blood flow near the surface of the skin so less heat is lost through radiation.
Fibrinolysis
Breakdown and removal of a clot begins within 2 days and continues for several more -plasminogen that trapped the clot is converted in to an enzyme called plasmin which digest the fibrin
How does the body prevent infections?
By the antibodies in the blood
Secondary polycythemia
Cause by: low O2 level or increased EPO, dehydration, emphysema, high altitude, or physical conditioning
Once a hematopoietic stem cell turns into a proerythroblast, it is _______________, it now can only be a RBC.
Committed
Why does blood have a higher density and viscosity than water?
Due to the presence of formed elements.
During which phase in erythrocyte development does the color of hemoglobin overcome the color of the stained ribosomes?
During phase 2, the cell's buildup of reddish hemoglobin overwhelms the blue color of the ribosomes.
Erythrocyte production controlled by?
EPO- Erythropoietin.
How can hemoglobin transport 4 molecules of oxygen?
Each Iron atom can combine reversibly with one molecule of Oxygen
What are the major contributors to blood viscosity?
Erythrocytes
What is the most dense component of blood?
Erythrocytes (RBCs) 45% Most dense component
Why aren't erythrocytes and platelets complete cells?
Erythrocytes lack a nucleus and organelles, which creates a biconcave shape. Platelets are cell fragments
Diapedesis (emigration)
Leukocytes move out of blood, squeeze through gaps (amoeboid motion) in the endothelial tissue and enter tissue fluid. Leukocytes seek out invaders and chase their scent (positive chemotaxis)
Imparied liver function
Liver disease can prevent liver from producing bile which is needed to absorb fat and vit-K This causes inability to synthesize procoagulants (clotting factors) Causes: vit k deficincy, hep, or cirrhosis
Which is the type of leukocyte responsible for targeting pathogens and antibody production?
Lymphocyte
Destruction of dead or dying blood cells is accomplished by
Macrophages in the spleen
What type of connective tissue cells are similar to Basophils in that they contain granules that release histamine to mediate the inflammatory response?
Mast Cells
Which of the following best explains how platelets enter the blood?
Megakaryocytes place platelets in the blood by passing them through the wall of sinusoidal capillaries (with large openings in their walls) in the bone marrow.
Production of RBC is an example of what type of feedback?
Negative feedback. Opposite effect of the original stimulus
How is bright red oxyhemoglobin formed?
Oxygen diffuses into the blood in the lungs and binds to hemoglobin
Why is oxygen related cell respiration?
Oxygen is needed for mitocondrias to produce ATP, without ATP cells will dye
Possible benefit of Sickle cell Anemia
People with SCA do not contract malaria, which kills 1 million each year.
Blood that has been centrifuged separates into 3 layers. What are they?
Plasma - 55% of whole blood Buffy coat (leukocytes and platelets)- <1% of whole blood Erythrocytes (RBC) - 45% of Whole blood HEMOCRIT
What makes up the greatest portion of whole blood by VOLMUE? And what percent?
Plasma -55%. It is least dense component
How does blood regulate body temperature?
Plasma absorbs and distributes heat. Blood vessels in dermis dilate (vasodilation) to cool body and to conserve heat.
What develops from lymphoid stem cells?
Plasma cells and effector t cells
Which formed element can be described as cytoplasmic fragments?
Platelets can be referred to as cytoplasmic fragments because they form as packets of cytoplasm are pinched off the megakaryocyte. Megakaryocytes are complete cells in the developmental pathway of thrombopoiesis.
Hematopoietic stem cells (hemocytoblast)
Precursor to blood cell formation. Adult blood forming cells begin maturation in red bone marrow from nucleated cells.
Blood plasma
The Straw colored (pale yellow) fluid portion of whole blood that consists of water (90%), nutrients, hormones, wastes, gases, proteins and inorganic ions (electrolytes)
Gelling of blood
The gelling of blood due to formation of insoluble fibrin occurs during the coagulation stage.
What part of the pathway to produce platelets is shared with other formed elements?
The hematopoietic stem cell (hemocytoblast) is the stem cell for all blood-formed elements.
What part of the hemoglobin molecule is eventually metabolized to stercobilin in the feces?
The heme group has its iron removed and recycled, while the remainder is converted to bilirubin and makes its way to the liver, where it is passed to the intestine in bile. Bacteria metabolize the bilirubin into stercobilin.
Why are leukocytes important?
They are our bodies defense against disease
How is it possible that erythrocytes do not consume any oxygen they carry?
They lack organelles and anaerobic ATP
Disorders of Hemostasis
Thromboembolytic disorders and bleeding disorders
True or false: Erythrocytes can bend and twist to fit through vessels
True
True or false: Most blood cells originate in the bone marrow and do not divide
True
What is blood?
a connective tissue that is the river of life consist of living cells called formed elements suspended in a nonliving fluid matrix called blood plasma - sustaining transport vehicle of the cardiovascular system.
Sickle Cell Anemia (SCA)
a genetic disorder that causes abnormal hemoglobin, resulting in some red blood cells assuming an abnormal sickle shape 1 amino acid is wrong in globin chain of 146 amino acids, usually #6 -misshaped RBC can rupture easily and block small vessels -Results in poor O2 delivery and pain -CAN CAUSE STROKES Treatment:acute crisis treated with transfusions
Bleeding disorders
abnormalities that prevent normal clot formation
phase two of coagulation
activated prothrombin produces thrombin
Hemocytoblasts give rise to:
all formed elements
What will happen if there isn't enough fluid around your heart?
blood pressure will drop
Too many RBCs increases
blood viscosity which creates clots
What color is blood in the arteries?
bright red
Platelets are
cell fragments, from Megakarocytes, -that help stop bleeding -granules contain serotonin life span: about 10 days
phagocytic cells
cells that engulf, ingest, and destroy foreign bodies or toxins
thrombus
clot that develop and persists in unbroken blood vessel -if large enough can block blood flow and circulation leading to tissue death
Thrombocytopenia
deficiency of circulating platelets and may result from an condition that suppress or destroys red bone marrow
T lymphocytes (T cells)
directly attack virus-infected cell or tumor cell -attach our own mutated or infected cells
Embolism
embolus obstructing a vessel ex: pulmonary(lung) or cerebral (brain) emboli Risk factors: atherosclerosis, inflammation, slowly flowing blood or blood stasis from immobility
Testosterone _________ EPO production and results in high RBC counts
enhances
Granules contain
enzymes or antimicrobial proteins that digest and destroy the invading organisms
What are the formed elements of blood?
erythrocytes(RBC) , leukocytes(WBC), platelets -Erythrocytes and Buffy Coat
Polycythemia
excess of red blood cells due to oxygen deficiency or disease. ex: bones marrow cancer May Increase blood viscosity, which causes poor blood flow and oxygen delivery. May form clots Treatment: Therapeutic phlebotomy remove RBC and treat cancer
Hemorrhagic anemia
excessive blood loss or slight but persistent ex: car accidents, cut artery or even ulcer in stomach
Aplastic anemia
failure of blood cell production in the bone marrow can be cause from drugs, virus, chemicals, radiation, Treatment: short term- transfusions Longterm: transplanted stem cells
Hemostasis
fast series of reactions for stoppage of bleeding; -requires clotting factors and substances released by platelets and injured tissues
When Iron is stored in cells it is called
ferritin and hemosiderin
Platelets are critical to the clotting process by
forming a temporary seal when a blood vessel breaks
Hemophilia
genetic condition that results in deficiency of factors *VIII (anti hemophilic factor), IX or XI *most common 77% of all Factor VII needed for phase 2 and 3
hematopietic stem cells are also known as
hemocytoblast
Balance between RBC production and destruction depends on
hormonal controls and dietary requirements
Thrombopoietin
hormone from liver stimulates platelet formation. takes place by repeated mitoses of megakaryocytic without cytokines
Erythropoietin (EPO)
hormone secreted by the kidney (small amount of liver) to stimulate the production of red blood cells by bone marrow
Vascular spasm
immediate vasoconstriction in response to blood vessel injury when tissue is damaged collagen fibers are exposed this releases chemicals -becomes more effective with increased tissue damage *reduce size of blood cells; less blood comes out
Too many erythrocytes or high oxygen levels in blood can _______ EPO production
inhibit
lymphocytic leukemia
involves lymphocytes
myeloid leukemia
involves myeloblast descendants (granulocytes and monocytes) 4 out of the 5 WBC (not lymphocytes)
positive chemotaxis
movement of a cell in the direction of a favorable chemical stimulus
From which cell do the granulocytes descend?
myeloblast -All three types of granular leukocytes descend from myelocytes.
All granulocytes are
phagocytic
What is the nonliving fluid matrix of blood?
plasma
What are the major components of whole blood?
plasma and formed elements (Erythrocytes and Buffy Coat-leukocytes and platelets)
What is the most abundant solutes by weight?
plasma proteins. Counts for 8% of plasma weight
Blood is composed of
plasma, red blood cells, white blood cells, platelets
Free iron is toxic so iron is bound with _________.
protein
Where is red bone marrow located?
proximal epiphyses(closest to the body) of humerous and femur
anticoagulant
slows coagulation and prevents new clots from forming -asprin, -heparin-used for pre and post op, -warfarin/coumadin used tor people prone to atrial fib. (interferes with action of vit K)
Microcytes
small pale iron deficient rbcs (plural)
What are the physical characteristics of blood?
sticky, opaque, heavier than water, alkaline, color depends on O2 content. Metallic taste
Vitamin K is needed for
synthesizing four of the clotting factors
phase three of coagulation
the formation of fibrin mesh from fibrinogen in the plasma
blood clotting process
the healing of cuts; this process keeps your blood from draining out and helps prevent the invasion of harmful bacteria
Which cells of the myeloid stem cell pathway have accumulated granules?
three of the fours pathways leading from myeloid stem cells are myelocytes and accumulate granules: eosinophilic, basophilic, and neutrophilic.
Emboli
thrombus freely floating in bloodstream that can be lodged in a small vessel and restrict blood flow
Symptoms of anemia include:
tiredness, headache, lightheadedness, pale, cold
What can too few RBCs lead to?
tissue hypoxia
Why is there always a small amount of EPO in blood
to maintain basal rate
Hemolytic anemia
too many RBC being destroyed Cause by: incompatible transfusions mismatched (wrong blood type) -bacterial or parasitic infections -Hemoglobin abnormalities (thalassemia and sickle cell)
When Iron is transported in blood bound to protein it is called?
transferrin
What is the major function of erythrocytes?
transport oxygen and carbon dioxide (gas transportation)
What is the function of erythrocytes?
transport respiratory gases in the blood on hemoglobin
What are the functions of blood?
transport, regulation, protection
What type of tissue is blood?
fluid connective tissue
One molecule of Hemoglobin protein consists of
globin proteins 4- polypeptide chains(2 alpha and 2 beta) , each with binding with red ring-like heme group Each Heme group has an Iron ion at the center.
Plasma proteins are
most abundant by weight dissolved solutes in plasma. Remain in blood; not taken up by cells for energy sources. they functions as a carrier, pH buffer most are created in the liver
How long do formed elements survive in the bloodstream?
only a few days
What determines if blood is dark or light?
oxygen
If Blood is dark red what does that mean?
oxygen poor
Hemoglobin is made up of
red heme pigment bound to the protein globin
Regulation functions of the blood include
-Maintaining body temperature by absorbing and distributing heat throughout the body and skin surface to encourage heat loss -Maintaining normal pH using buffers; Blood act as the "alkaline reserve" of bicarbonate ions -Maintaining adequate fluid volume in circulatory system
The drop in normal blood oxygen levels the trigger EPO formation can result from:
-Reduced numbers of red blood cells due to hemorrhages (bleeding) or excessive RBC destruction -Insufficient hemoglobin per RBC (as iron deficiency) -Reduced availability to oxygen, as might occur at his altitudes or pneumonia
Albumin
-accounts for 60% of plasma proteins -functions as a carrier, pH buffer -major blood protein that contributes to the plasma osmotic pressure (the pressure that helps keep water in the blood stream)
What triggers erythropoietin (EPO) production to make new red blood cells?
-excessive loss of RBCs -insufficient hemoglobin -reduced availability of oxygen -can be enhanced by testosterone
leukocytes and platelets make up ___% of blood
1
A single red blood cell can contain about 250 million hemoglobin molecules. How many molecules of oxygen can it carry?
1 billion molecules of oxygen. 250 million hemoglobin molecules x 4 iron binding sites for oxygen= 1 billion molecules of oxygen
When the reticulocyte enter the blood stream, how long does it take for it to be fully mature?
2 days
What is the complete hemoglobin molecule composed of?
2- alpha and 2- beta polypeptide chains (globins), heme groups, and iron ions
What is the % of carbon dioxide that forms carbminohemoglobin?
20%
Give an example of complementarity of structure and function
A red blood cells anatomy allows the function to happen. The aneucleated nucleus and lack of mitochondria allows for more Hb(hemoglobin). More volume and surface which allows for more space for oxygen to transport.
What part of the body does erythropoietin (EPO) target to increase erythropoiesis?
Red marrow, is the site of blood cell production and is stimulated by erythropoietin. The kidneys are not the target organ for erythropoietin (EPO). The kidneys do not make red blood cells.
Vasoconstriction
Reduces blood flow and heat transfer by decreasing the diameter of superficial blood vessels. The blood will flow to the more vital organs.
What is a young, anucleate erythrocyte called?
Reticulocyte Reticulocytes are a stage in erythrocyte development when the nucleus has just been lost. These are found in circulating blood, but they are typically only a small percent 1%-2% of total red cells
How does a centrifuge separate blood?
by weight
carbaminohemoglobin
carbon dioxide bound to amino acids of globin of Hb
What color is blood in the veins
dark red
Hypoxic
deficient in oxygen
What is the most abundant solutes in blood plasma?
electrolytes