Anatomy & Physiology Part 2 Exam 1

pluripotent stem cells

About 0.05-0.1% of red bone marrow cells are derived from mesenchyme (tissue from which almost all connective tissues develop) and are called _________________. These cells have the capacity to develop into many different types of cells.

lysozyme, strong oxidants

After engulfing a pathogen during phagocytosis, a neutrophil unleashes several chemicals to destroy the pathogen. These chemicals include the enzyme ___________ ,which destroys certain bacteria, and _____________,such as the superoxide anion (O2-), hydrogen peroxide (H2O2), and the hypochlorite anion (OCl-), which is similar to household bleach.

leukopenia

An abnormally low level of white blood cells (below 5000/muL) is termed _____________. It is never beneficial and may be caused by radiation, shock, and certain chemotherapeutic agents.

aspirin

At low doses, ____________ inhibits vasoconstriction and platelet aggregation by blocking synthesis of thromboxane A2. It also reduces the chance of thrombus formation. Due to these effects, this prior pain relief drug reduces the risk of transient ischemic attacks (TIA), strokes, myocardial infarction, and blockage of peripheral arteries.

thrombosis, thrombus

Clotting in an unbroken blood vessel (usually a vein) is called _____________. The clot itself, called a ____________, may dissolve spontaneously. If it remains intact, however, it may become dislodged and be swept away in the blood.

clotting factors

Clotting involves several substances known as _______________. These factors include calcium ions (Ca2+), several inactive enzymes that are synthesized by hepatocytes (liver cells) and released into the bloodstream, and various molecules associated with platelets or released by damaged tissues. Most clotting factors are identified by Roman numerals that indicate the order of their discovery (not necessarily the order of their participation in the clotting process).

platelets, platelet derived growth factor

Considering their small size, _________ store an impressive array of chemicals. Within many vesicles are clotting factors, ADP, ATP, Ca2+, and serotonin. Also present are enzymes that produce thromboxane A2, a prostaglandin; fibrin-stabilizing factor, which helps to strengthen a blood clot; lysosomes; some mitochondria; membrane systems that take up and store calcium and provide channels for release of the contents of granules; and glycogen. Also within platelets is ___________________, a hormone that can cause proliferation of vascular endothelial cells, vascular smooth muscle fibers, and fibroblasts to help repair damaged blood vessel walls.

progenitor cells

During hemopoiesis, some of the myeloid stem cells differentiate into ____________

basophils

High count of ___________ may indicate allergic reactions, leukemias, cancers, or hypothyroidism. A low count may indicate pregnancy, ovulation, stress, or hyperthyroidism.

eosinophils

High count of ___________ may indicate allergic reactions, parasitic infections, or autoimmune diseases. A low count may indicate drug toxicity or stress.

neutrophils

High count of ___________ may indicate bacterial infections, burns, stress, and inflammation. A low count of these may indicate Radiation exposure, drug toxicity, vitamin B12 deficiency, systemic lupus erythematosus (SLE).

lymphocytes

High count of ___________ may indicate viral infections and some leukemias. A low count of these may indicate prolonged illnesses, immunosuppression, or treatment with cortisol.

monocytes

High count of ___________ may indicate viral or fungal infections, tuberculosis, some leukemias, or other chronic diseases. A low count may indicate bone marrow suppression or treatment with cortisol.

the iron is recycled, the globins may be reused or broken down into amino acids

How is hemoglobin recycled?

polycythemia

In _____________ the percentage of RBCs is abnormally high, and the hematocrit may be 65% or higher. This raises the viscosity of blood, which increases the resistance to flow and makes the blood more difficult for the heart to pump. Increased viscosity also contributes to high blood pressure and increased risk of stroke. Causes include abnormal increases in RBC production, tissue hypoxia, dehydration, and blood doping or the use of EPO by athletes.

defensins

Neutrophils also contain ______________, proteins that exhibit a broad range of antibiotic activity against bacteria and fungi. They form peptide "spears" that poke holes in microbe membranes; the resulting loss of cellular contents kills the invader.

phagocytosis

Neutrophils and macrophages are active in ______________; they can ingest bacteria and dispose of dead matter.

vitamin K

Normal clotting depends on adequate levels of _____________ in the body. Although __(same)__ is not involved in actual clot formation, it is required for the synthesis of four clotting factors. Normally produced by bacteria that inhabit the large intestine, __(same)__ is a fat-soluble vitamin that can be absorbed through the lining of the intestine and into the blood if absorption of lipids is normal. People suffering from disorders that slow absorption of lipids (for example, inadequate release of bile into the small intestine) often experience uncontrolled bleeding as a consequence of __(same)__ deficiency.

vascular spasm

When arteries or arterioles are damaged, the circularly arranged smooth muscle in their walls contracts immediately, a reaction called ____________. This reduces blood loss for several minutes to several hours, during which time the other hemostatic mechanisms go into operation. The spasm is probably caused by damage to the smooth muscle, by substances released from activated platelets, and by reflexes initiated by pain receptors.

colony stimulating factors, interleukins

Two important families of cytokines that stimulate white blood cell formation are _________________, _______________.

reticulocyte

Ultimately, a cell near the end of the development sequence ejects its nucleus and becomes a ______________. Loss of the nucleus causes the center of the cell to indent, producing the red blood cell's distinctive biconcave shape. __(same)__ retain some mitochondria, ribosomes, and endoplasmic reticulum. They pass from red bone marrow into the bloodstream by squeezing between the endothelial cells of blood capillaries. __(same)__ develop into mature red blood cells within 1 to 2 days after their release from red bone marrow.

leukocytes

Unlike red blood cells, white blood cells or ______________ have nuclei and a full complement of other organelles but they do not contain hemoglobin.

granular, agranular

WBCs are classified as either ____________ or ____________, depending on whether they contain conspicuous chemical-filled cytoplasmic granules (vesicles) that are made visible by staining when viewed through a light microscope.

transportation, regulation, protection

What are three primary functions of blood?

biconcave discs

What is the shape of erythrocytes?

Negative feedback regulation of erythropoiesis

What is this describing?

thrombolytic agents

____________________ are chemical substances that are injected into the body to dissolve blood clots that have already formed to restore circulation. They either directly or indirectly activate plasminogen.

myeloid, lymphoid

monocytes and granular leukocytes develop from ____________ stem cells. In contrast, lymphocytes develop from ___________ stem cells.

plasma 55%, cells 45%

two components of blood? give percentage of each

Red Blood Cell Life Cycle

-G1 Macrophages in the spleen, liver, or red bone marrow phagocytize ruptured and worn-out red blood cells. -G2 The globin and heme portions of hemoglobin are split apart. G3 Globin is broken down into amino acids, which can be reused to synthesize other proteins. -G4 Iron is removed from the heme portion in the form of Fe3+, which associates with the plasma protein transferrin, a transporter for Fe3+ in the bloodstream. -G5 In muscle fibers, liver cells, and macrophages of the spleen and liver, Fe3+ detaches from transferrin and attaches to an iron-storage protein called ferritin. -G6 On release from a storage site or absorption from the gastrointestinal tract, Fe3+ reattaches to transferrin. -G7 The Fe3+-transferrin complex is then carried to red bone marrow, where RBC precursor cells take it up through receptor- mediated endocytosis for use in hemoglobin synthesis. Iron is needed for the heme portion of the hemoglobin molecule, and amino acids are needed for the globin portion. Vitamin B12 is also needed for the synthesis of hemoglobin. -G8 Erythropoiesis in red bone marrow results in the production of red blood cells, which enter the circulation. -G9 When iron is removed from heme, the non-iron portion of heme is converted to biliverdin, a green pigment, and then into bilirubin, a yellow-orange pigment. -G10 Bilirubin enters the blood and is transported to the liver. -G11 Within the liver, bilirubin is released by liver cells into bile, which passes into the small intestine and then into the large intestine. -G12 In the large intestine, bacteria convert bilirubin into urobilinogen. -G13 Some urobilinogen is absorbed back into the blood, converted to a yellow pigment called urobilin, and excreted in urine. -G14 Most urobilinogen is eliminated in feces in the form of a brown pigment called stercobilin, which gives feces its characteristic color.

biconcave disc

A ____________ has a much greater surface area for the diffusion of gas molecules into and out of the RBC than would, say, a sphere or a cube.

bone marrow transplant

A _________________ is the replacement of cancerous or abnormal red bone marrow with healthy red bone marrow in order to establish normal blood cell counts. In patients with cancer or certain genetic diseases, the defective red bone marrow is destroyed by high doses of chemotherapy and whole body radiation just before the transplant takes place. These treatments kill the cancer cells and destroy the patient's immune system in order to decrease the chance of transplant rejection.

embolus, pulmonary embolism

A blood clot, bubble of air, fat from broken bones, or a piece of debris transported by the bloodstream is called an _____________. One that breaks away from an arterial wall may lodge in a smaller-diameter artery downstream and block blood flow to a vital organ. When one lodges in the lungs, the condition is called ________________.

thrombin

A clot does not extend beyond a wound site into the general circulation, in part because fibrin absorbs ___________ into the clot.

globin, heme

A hemoglobin molecule consists of a protein called ___________, composed of four polypeptide chains (two alpha and two beta chains); a ring-like nonprotein pigment called a ________ is bound to the four chains, at the center of which is an iron ion.

cord blood transplant

A more recent advance for obtaining stem cells involves a ___________________. The connection between the mother and embryo (and later the fetus) is the umbilical cord. Stem cells may be obtained from the umbilical cord shortly after birth. The stem cells are removed from the cord with a syringe and then frozen. Stem cells from the cord have several advantages over those obtained from red bone marrow: 1. They are easily collected following permission of the newborn's parents. 2. They are more abundant than stem cells in red bone marrow. 3. They are less likely to cause graft-versus-host disease, so the match between donor and recipient does not have to be as close as in a bone marrow transplant. This provides a larger number of potential donors. 4. They are less likely to transmit infections. 5. They can be stored indefinitely in cord-blood banks.

differential white blood cell count

A physician may order a _________________________, a count of each of the five types of white blood cells, to detect infection or inflammation, determine the effects of possible poisoning by chemicals or drugs, monitor blood disorders (for example, leukemia) and the effects of chemotherapy, or detect allergic reactions and parasitic infections. Because each type of white blood cell plays a different role, determining the percentage of each type in the blood assists in diagnosing the condition.

anemia

A significant drop in hematocrit indicates ___________, a lower-than-normal number of RBCs.

blood groups, blood types

Based on the presence or absence of various antigens, blood is categorized into different _________________. Within a given blood group, there may be two or more different _______________.

mitochondria

Because RBCs lack ______________ and generate ATP anaerobically (without oxygen), they do not use up any of the oxygen they transport.

oxygen

Because mature RBCs have no nucleus, all their internal space is available for ________ transport.

thrombopoietin, platelet

Besides the immature cell types that develop into erythrocytes and leukocytes, hemopoietic stem cells also differentiate into cells that produce platelets. Under the influence of the hormone __________________, myeloid stem cells develop into megakaryocyte colony-forming cells that in turn develop into precursor cells called megakaryoblasts. Megakaryoblasts transform into megakaryocytes, huge cells that splinter into 2000 to 3000 fragments. Each fragment, enclosed by a piece of the plasma membrane, is a ____________ (thrombocyte). Thrombocytes break off from the megakaryocytes in red bone marrow and then enter the blood circulation. Between 150,000 and 400,000 thrombocytes are present in each microliter of blood. Each is irregularly disc-shaped, 2-4 mu m in diameter, and has many vesicles but no nucleus. Their granules contain chemicals that, once released, promote blood clotting. thrombocytes help stop blood loss from damaged blood vessels by forming a platelet plug. Platelets have a short life span, normally just 5 to 9 days. Aged and dead thrombocytes are removed by fixed macrophages in the spleen and liver.

8

Blood constitutes __% of total body mass.

blood, blood plasma

Blood is a liquid connective tissue that ___________ consists of cells surrounded by a liquid extracellular matrix. The extracellular matrix is called _______________, and it suspends various cells and cell fragments.

hypoxia

Cellular oxygen deficiency, called ____________, may occur if too little oxygen enters the blood. For example, the lower oxygen content of air at high altitudes reduces the amount of oxygen in the blood.

antithrombin, heparin

In addition, substances that delay, suppress, or prevent blood clotting, called anticoagulants, are present in blood. These include _______________, which blocks the action of several factors, including XII, X, and II (prothrombin). ___________, an anticoagulant that is produced by mast cells and basophils, combines with __(same as first blank)__ and increases its effectiveness in blocking thrombin.

myeloid stem cells, lymphoid stem cells

In order to form blood cells, pluripotent stem cells in red bone marrow produce two further types of stem cells, which have the capacity to develop into several types of cells. These stem cells are called _______________ and ________________.

precursor cells

In the next generation, progenitor cells are called ______________, also known as blasts.

albumin

Most numerous plasma protein in the blood plasma

clot retraction

Once a clot is formed, it plugs the ruptured area of the blood vessel and thus stops blood loss. ________________ is the consolidation or tightening of the fibrin clot. The fibrin threads attached to the damaged surfaces of the blood vessel gradually contract as platelets pull on them. As the clot retracts, it pulls the edges of the damaged vessel closer together, decreasing the risk of further damage. During retraction, some serum can escape between the fibrin threads, but the formed elements in blood cannot. Normal retraction depends on an adequate number of platelets in the clot, which release factor XIII and other factors, thereby strengthening and stabilizing the clot. Permanent repair of the blood vessel can then take place. In time, fibroblasts form connective tissue in the ruptured area, and new endothelial cells repair the vessel lining.

anemia

Oxygen delivery may also fall due to __________, which has many causes: Lack of iron, lack of certain amino acids, and lack of vitamin B12 are but a few (see Disorders: Homeostatic Imbalances at the end of this chapter). Circulatory problems that reduce blood flow to tissues may also reduce oxygen delivery. Whatever the cause, hypoxia stimulates the kidneys to step up the release of erythropoietin, which speeds the development of proerythroblasts into reticulocytes in the red bone marrow. As the number of circulating RBCs increases, more oxygen can be delivered to body tissues.

emigration, adhesion molecules

RBCs are contained within the bloodstream, but WBCs leave the bloodstream by a process termed _____________, also called diapedesis, in which they roll along the endothelium, stick to it, and then squeeze between endothelial cells. Molecules known as ___________________ help WBCs stick to the endothelium.

erythrocytes

Red Blood Cells are also known as ______________

chemotaxis

Several different chemicals released by microbes and inflamed tissues attract phagocytes, a phenomenon called ___________.

hemopoietic growth factors

Several hormones called ___________________ regulate the differentiation and proliferation of particular progenitor cells.

prostacyclin

Several other mechanisms also control blood clotting. For example, endothelial cells and white blood cells produce a prostaglandin called _____________ that opposes the actions of thromboxane A2. It is a powerful inhibitor of platelet adhesion and release.

plasma proteins

Some of the proteins in blood plasma are also found elsewhere in the body, but those confined to blood are called ______________. Hepatocytes (liver cells) synthesize most of these.

fibrinolytic system, fibrinolysis, plasmin

The _________________ dissolves small, inappropriate clots; it also dissolves clots at a site of damage once the damage is repaired. Dissolution of a clot is called ______________. When a clot is formed, an inactive plasma enzyme called plasminogen is incorporated into the clot. Both body tissues and blood contain substances that can activate plasminogen to __________ or fibrinolysin, an active plasma enzyme.

thrombopoietin

Thrombopoietin is a hormone produced by the liver that stimulates the formation of platelets (thrombocytes) from megakaryocytes.

intrinsic pathway

The _________________ of blood clotting is more complex than the extrinsic pathway, and it occurs more slowly, usually requiring several minutes. The intrinsic pathway is so named because its activators are either in direct contact with blood or contained within (intrinsic to) the blood; outside tissue damage is not needed. If endothelial cells become roughened or damaged, blood can come in contact with collagen fibers in the connective tissue around the endothelium of the blood vessel. In addition, trauma to endothelial cells causes damage to platelets, resulting in the release of phospholipids by the platelets. Contact with collagen fibers (or with the glass sides of a blood collection tube) activates clotting factor XII, which begins a sequence of reactions that eventually activates clotting factor X. Platelet phospholipids and Ca2+ can also participate in the activation of factor X. Once factor X is activated, it combines with factor V to form the active enzyme prothrombinase (just as occurs in the extrinsic pathway), completing the intrinsic pathway.

hematology

The branch of science concerned with the study of blood, blood-forming tissues, and the disorders associated with them is ____________.

prothrombinase

The extrinsic pathway of blood clotting has fewer steps than the intrinsic pathway and occurs rapidly—within a matter of seconds if trauma is severe. It is so named because a tissue protein called tissue factor (TF), also known as thromboplastin, leaks into the blood from cells outside (extrinsic to) blood vessels and initiates the formation of ________________. TF is a complex mixture of lipoproteins and phospholipids released from the surfaces of damaged cells. In the presence of Ca2+, TF begins a sequence of reactions that ultimately activates clotting factor X. Once factor X is activated, it combines with factor V in the presence of Ca2+ to form the active enzyme __(same)__ , completing the extrinsic pathway.

common pathway

The formation of prothrombinase marks the beginning of the _______________. In the second stage of blood clotting, prothrombinase and Ca2+ catalyze the conversion of prothrombin to thrombin. In the third stage, thrombin, in the presence of Ca2+, converts fibrinogen, which is soluble, to loose fibrin threads, which are insoluble. Thrombin also activates factor XIII (fibrin stabilizing factor), which strengthens and stabilizes the fibrin threads into a sturdy clot. Plasma contains some factor XIII, which is also released by platelets trapped in the clot. Thrombin has two positive feedback effects. In the first positive feedback loop, which involves factor V, it accelerates the formation of prothrombinase. Prothrombinase in turn accelerates the production of more thrombin, and so on. In the second positive feedback loop, thrombin activates platelets, which reinforces their aggregation and the release of platelet phospholipids.

red blood cells, white blood cells, platelets

The formed elements of the blood include three principal components:

nitric oxide

The gaseous hormone ________________, produced by the endothelial cells that line blood vessels, binds to hemoglobin. Under some circumstances, hemoglobin releases it. This released gaseous hormone causes vasodilation, an increase in blood vessel diameter that occurs when the smooth muscle in the vessel wall relaxes. Vasodilation improves blood flow and enhances oxygen delivery throughout the body.

neutrophil

The granules of a ____________ are smaller than those of other granular leukocytes, evenly distributed, and pale lilac. Because the granules do not strongly attract either the acidic (red) or basic (blue) stain, these WBCs are neutrophilic (neutral loving). The nucleus has *two to five lobes, connected by very thin strands of nuclear material*. As the cells age, the number of nuclear lobes increases. Because older cells have several differently shaped nuclear lobes, they are often called polymorphonuclear leukocytes (PMNs), polymorphs, or "polys." Their functions include Phagocytosis, Destruction of bacteria with lysozyme, defensins, and strong oxidants, such as superoxide anion, hydrogen peroxide, and hypochlorite anion.

eosinophil

The large, uniform-sized granules within an ______________ are stained red-orange with acidic dyes. The granules usually do not cover or obscure the nucleus, which most often has two lobes connected by either a thin strand or a thick strand of nuclear material. Their functions include combating effects of histamine in allergic reactions, phagocytizing antigen-antibody complexes, and destroying certain parasitic worms.

monocyte

The nucleus of a ____________ is usually kidney-shaped or horseshoe-shaped, and the cytoplasm is blue-gray and has a foamy appearance. The cytoplasm's color and appearance are due to very fine azurophilic granules, which are lysosomes. Blood is merely a conduit for __(same)__, which migrate from the blood into the tissues, where they enlarge and differentiate into macrophages. Some become fixed (tissue) macrophages, which means they reside in a particular tissue; examples are alveolar macrophages in the lungs or macrophages in the spleen. Others become wandering macrophages, which roam the tissues and gather at sites of infection or inflammation. Their functions include phagocytosis (after transforming into fixed or wandering macrophages).

lymphocyte

The nucleus of a _____________ stains dark and is round or slightly indented. The cytoplasm stains sky blue and forms a rim around the nucleus. The larger the cell, the more cytoplasm is visible. Lymphocytes are classified by cell diameter as large or small. Although the functional significance of the size difference between small and large is unclear, the distinction is still clinically useful because an increase in the number of large cells has diagnostic significance in acute viral infections and in some immunodeficiency diseases. Their functions include mediating immune responses, including antigen-antibody reactions. The B cells develop into plasma cells, which secrete antibodies. T cells attack invading viruses, cancer cells, and transplanted tissue cells. Natural killer cells attack wide variety of infectious microbes and certain spontaneously arising tumor cells.

hematocrit

The percentage of total blood volume occupied by RBCs is called the ___________.

hemopoiesis

The process by which the formed elements of blood develop is called ____________

clotting

The process of gel formation, called __________ or coagulation, is a series of chemical reactions that culminates in formation of fibrin threads. If blood clots too easily, the result can be thrombosis—clotting in an undamaged blood vessel. If the blood takes too long to clot, hemorrhage can occur.

basophil

The round, variable-sized granules of a ____________ are basic loving—they stain blue-purple with basic dyes. The granules commonly obscure the nucleus, which has two lobes. Their functions include liberating heparin, histamine, and serotonin in allergic reactions that intensify overall inflammatory response.

toxins, kinins, colony stimulating factors

The substances that provide stimuli for chemotaxis include __________ produced by microbes; __________, which are specialized products of damaged tissues; and some of the ____________________ (CSFs).

antigens, agglutinogens

The surfaces of erythrocytes contain a genetically determined assortment of ___________ composed of glycoproteins and glycolipids. These __(same as above)__, called ________________, occur in characteristic combinations.

24, 100

There are at least ____ blood groups and more than ____ antigens that can be detected on the surface of red blood cells.

immunoglobulins

This plasma protein helps attack viruses and bacteria. Alpha and beta versions transport iron, lipids, and fat-soluble vitamins.

albumin, globulins, fibrinogen

Three types of plasma proteins

vascular spasm, platelet plug formation, coagulation

When blood vessels are damaged or ruptured, the hemostatic response must be quick, localized to the region of damage, and carefully controlled in order to be effective. Three mechanisms reduce blood loss: (1) ______________, (2) __________________, and (3) ________________. When successful, hemostasis prevents hemorrhage, the loss of a large amount of blood from the vessels. Hemostatic mechanisms can prevent hemorrhage from smaller blood vessels, but extensive hemorrhage from larger vessels usually requires medical intervention.

major histocompatibility antigens

White blood cells and all other nucleated cells in the body have proteins, called ________________________, protruding from their plasma membrane into the extracellular fluid. These "cell identity markers" are unique for each person (except identical twins).

clotting

___________ can be divided into three stages: -Two pathways, called the extrinsic pathway and the intrinsic pathway, which will be described shortly, lead to the formation of prothrombinase. Once prothrombinase is formed, the steps involved in the next two stages of clotting are the same for both the extrinsic and intrinsic pathways, and together these two stages are referred to as the common pathway. - Prothrombinase converts prothrombin (a plasma protein formed by the liver) into the enzyme thrombin. -Thrombin converts soluble fibrinogen (another plasma protein formed by the liver) into insoluble fibrin. Fibrin forms the threads of the clot.

cytokines

____________ are small glycoproteins that are typically produced by cells such as red bone marrow cells, leukocytes, macrophages, fibroblasts, and endothelial cells. They generally act as local hormones (autocrines or paracrines). These small glycoproteins stimulate proliferation of progenitor cells in red bone marrow and regulate the activities of cells involved in nonspecific defenses (such as phagocytes) and immune responses (such as B cells and T cells).

myeloid

____________ stem cells begin their development in red bone marrow and give rise to red blood cells, platelets, monocytes, neutrophils, eosinophils, and basophils.

lymphoid

____________ stem cells begin their development in red bone marrow but complete it in lymphatic tissues; they give rise to lymphocytes.

Interstitial fluid

_____________ is the fluid that bathes body cells and is constantly renewed by the blood.

granular, agranular

_____________ leukocytes include neutrophils, eosinophils, and basophils; _____________ leukocytes include lymphocytes and monocytes.

hemoglobin

______________ also transports about 23% of the total carbon dioxide, a waste product of metabolism. (The remaining carbon dioxide is dissolved in plasma or carried as bicarbonate ions.) As blood flows through the lungs, the carbon dioxide is released from this and then exhaled.

Hemostasis

______________, not to be confused with the very similar term homeostasis, is a sequence of responses that stops bleeding.

Leukocytosis

_______________ , an increase in the number of WBCs above 10,000/muL, is a normal, protective response to stresses such as invading microbes, strenuous exercise, anesthesia, and surgery.

erythropoiesis, proerythroblast

_______________, the production of RBCs, starts in the red bone marrow with a precursor cell called a _______________. This cell divides several times, producing cells that begin to synthesize hemoglobin.

erythropoietin

________________ or EPO increases the number of red blood cell precursors. EPO is produced primarily by cells in the kidneys that lie between the kidney tubules (peritubular interstitial cells). With renal failure, EPO release slows and RBC production is inadequate. This leads to a decreased hematocrit, which leads to a decreased ability to deliver oxygen to body tissues.

activated protein C

________________, inactivates the two major clotting factors not blocked by antithrombin and enhances activity of plasminogen activators. Babies that lack the ability to produce __(same)__ due to a genetic mutation usually die of blood clots in infancy.

red bone marrow

_________________ is a highly vascularized connective tissue located in the microscopic spaces between trabeculae of spongy bone tissue. It is present chiefly in bones of the axial skeleton, pectoral and pelvic girdles, and the proximal epiphyses of the humerus and femur.

lipid soluble hormones

_________________ require a carrier protein for transport in the watery environment of the blood Once they arrive at their destination, however, they are able to freely pass through the plasma membrane to bind to receptors located in the cytoplasm or the nucleus of the target cell

water soluble hormones

__________________ are easy to transport in the watery blood. The plasma membrane of target cells, however, is impermeable to them Water soluble hormones exert their effects by binding to receptors exposed to the interstitial fluid on the surface of target cells the hormone binding to its receptor acts as the first messenger in a cascade of signal transduction. The first messenger (the hormone) then causes production of a second messenger inside the cell, where specific hormone-stimulated responses take place One common second messenger is cyclic AMP (cAMP). Neurotransmitters, neuropeptides, and several sensory transduction mechanisms (vision) also act via second-messenger systems.

water soluble hormones

__________________ include peptide and protein hormones (and others with an amine group), and a group of local hormones derived from the arachidonic acid on our cell membranes called eicosanoids. -Peptide hormones and protein hormones are amino acid polymers. -The two major types of eicosanoids are prostaglandins and leukotrienes - both play a role in mediating the inflammatory response.

lipid soluble hormones

_____________________ consist of steroid hormones, thyroid hormones, and the gas nitric oxide. -Steroid hormones are derived from cholesterol. -Thyroid hormones (T3 and T4) are synthesized by attaching iodine to the amino acid tyrosine. -The gas nitric oxide (NO) is both a hormone and a neurotransmitter. Its synthesis is catalyzed by the enzyme nitric oxide synthase.

Platelet plug formation

_____________________ occurs as follows: - Initially, platelets contact and stick to parts of a damaged blood vessel, such as collagen fibers of the connective tissue underlying the damaged endothelial cells. This process is called platelet adhesion. -Due to adhesion, the platelets become activated, and their characteristics change dramatically. They extend many projections that enable them to contact and interact with one another, and they begin to liberate the contents of their vesicles. This phase is called the platelet release reaction. Liberated ADP and thromboxane A2 play a major role by activating nearby platelets. Serotonin and thromboxane A2 function as vasoconstrictors, causing and sustaining contraction of vascular smooth muscle, which decreases blood flow through the injured vessel. -The release of ADP makes other platelets in the area sticky, and the stickiness of the newly recruited and activated platelets causes them to adhere to the originally activated platelets. This gathering of platelets is called platelet aggregation. Eventually, the accumulation and attachment of large numbers of platelets form a mass called a platelet plug.

oxygen, carbon dioxide

blood transports __________ from the lungs and nutrients from the gastrointestinal tract, which diffuse from the blood into the interstitial fluid and then into body cells. ______________ and other wastes move in the reverse direction, from body cells to interstitial fluid to blood. Blood then transports the wastes to various organs—the lungs, kidneys, and skin—for elimination from the body.

hemoglobin

erythrocytes contain the oxygen-carrying protein ___________, which is a pigment that gives whole blood its red color.