Bio 252 Exam 4 Questions and Complete Solutions Graded A+

Bio 252 Exam 4 Questions and Complete Solutions Graded A+ what does the circulatory system consist of ? - Answer: heart, blood vessels, and the blood what is hematology - Answer: the study of blood what is the fundamental purpose of the circulatory system? - Answer: transport substances from place to place in the body what are the three main functions of the circulatory system ? - Answer: transport , protection, and regulation list five ways in which the circulatory system helps with transport - Answer: 1. blood carries O2 from the lungs to all of the body's tissue, while it picks up carbon dioxide from those tissues and carries it to the lungs to be removed from the body 2. picks up nutrients from the digestive tract and delivers them to all of the body's tissues 3. carries metabolic wastes to the kidneys for removal 4. carries hormones from endocrine cells to their target organs 5. it transports a variety of stem cells from the bone marrow and other origins to the tissues where they lodge and mature list 4 ways in which the circulatory system protects the body - Answer: 1. blood plays a role in inflammation 2. white blood cells destroy microoragnisms and cancer cells 3. antibodies and other blood proteins neutralize toxins and help to destroy pathogens 4. platelets secrete factors that initiate blood clotting list 3 ways in which the circulatory system is involved in regulation - Answer: 1. by absorbing or giving off fluid under different conditions, the blood capillaries help to stabilize fluid distribution in the body 2. by buffering acids and bases, blood proteins help to stabilize the pH of the extracellular fluid 3. shifts in blood flow help to regulate body temperature by routing blood to the skin for heat lost or retaining it deeper in the body to conserve heat true or false: adults generally have about 4 to 6 liters of blood. - Answer: true what is the matrix of the blood called____ - Answer: plasma ____ is a clear, light yellow fluid constituting a litter over half of the blood volume - Answer: plasma within the plasma are the formed elements.... what are those elements - Answer: red blood cells, white blood cells, and platelets what is another name for a red blood cells - Answer: erythrocytes what is another name for a white blood cells - Answer: leukocytes what are the two types of white blood cells - Answer: granulocytes and agranulocytes what are the three types of granulocytes - Answer: neutrophils, esosinophils, basophils what are the two types of agranulocytes - Answer: lymphocytes and monocytes how can you separate elements of the blood - Answer: put a sample into a centrifuge _____ are the densest formed element and constitute of about 37-52% of the total volume of a blood sample. - Answer: red blood cells the percentage of red blood cells in a sample is called a ___ - Answer: hemacrit ____ and ___ settle into a narrow cream or buff colored zone in a blood sample. They consists of 1% or less of the blood volume. - Answer: white blood cells and platelets _____ is at the top of the tube in a sample of blood and is the least dense. it accounts for 47-63% of the blood volume - Answer: plasma _____ is a complex mixture of water, proteins, nutrients, electrolytes, nitrogenous waste, hormones, and gases. - Answer: plasma when the blood clots and solids are removed, the remaining fluid is blood ____. - Answer: serum what makes serum different from plasma - Answer: it lacks the clotting protein fibrinogen what are some functions of the plasma proteins - Answer: clotting, defense, transport of other solutes such as iron, copper, lipids, and hydrophobic hormones what are the three types of plasma proteins - Answer: albumins, globulins, and fibrinogen _____ is the smallest and most abundant plasma protein. - Answer: albumin what is the function of albumin - Answer: transport various solutes and buffer the pH of the plasma what two properties of blood does albumin influence - Answer: viscosity and osmolarity true or false: changes in albumin concentration can significantly affect blood volume, pressure, and flow. - Answer: true what are the three types of globulins from smallest to largest - Answer: alpha, beta, gamma what roles do globulins play - Answer: they play a role in solute transport, clotting, and immunity _____is a sticky protein that forms the framework of a blood clot and it is a precursor for fibrin . - Answer: fibrinogen true or false: in addition to protein, the blood plasma contains nitrogen-containing compounds - Answer: true ____ are toxic end products of catabolism. - Answer: nitrogenous wastes what is the most abundant nitrogenous waste in the plasma - Answer: urea ____ is a product of amino acid catabolism - Answer: urea true or false: the plasma also transport nutrients absorbed by the digestive tract and dissolved oxygen, carbon dioxide, and nitrogen - Answer: true electrolytes are also an important component of the blood plasma. true or false - Answer: true ____ ions make up about 90% of the plasma cations - Answer: sodium (Na+) why is sodium an important solute for the blood plasma - Answer: it affects the osmolarity of the blood, blood volume and blood pressure what are two major properties of the blood - Answer: viscosity and osmolarity ____ is the resistance of a fluid to flow, resulting form the cohesion of it particles. (the thickness or stickiness of the blood) - Answer: viscosity true or false: whole blood is 4.5 to 5.5 times more viscous than water - Answer: true what makes the whole blood so viscous - Answer: the red blood cells true or false: plasma is 3 times more viscous than water - Answer: false; 2 what is viscosity important in the circulatory system - Answer: it governs the flow of blood through the vessels _____ of blood is the total molarity of dissolved particles that cannot pass through the blood vessel wall. This is more important in cardiovascular function - Answer: osmolarity what does it mean if the blood osmolarity is too high - Answer: the bloodstream absorbs too much water what is the result of a high blood osmolarity - Answer: increase blood volume=high blood pressure= strain on heart and arteries what does it mean if the blood osmolarity is too low - Answer: too much water remains in the tissues what is the result of a low blood osmolarity - Answer: the tissues will become swollen (edematous) and the blood pressure would be very low The blood osmolarity is a product mainly of its ____, ____ and ____ - Answer: sodium ions, protein, and erythrocytes what is another name for blood osmotic pressure - Answer: colloid osmotic pressure (COP) true or false: the adult produces 400 billion platelets, 200 billion RBCs and 10 billion WBC - Answer: true the formation of blood is called ____ - Answer: hemopoiesis the tissues that produce blood cells are called _____ tissues - Answer: hemopoietic the first hemopoietic tissues of the human embryo form in the _____ - Answer: yolk sac A____ is a membrane associated with all vertebrae embryos. In most vertebrates (fish, amphibians, reptiles, and birds) it encloses the egg yolk, transfers nutrients to the growing embryo, and produces the forerunners of the first blood cells. It also is a good source for cells that later produce eggs and sperm - Answer: yolk sac true or false: even animals that do not lay eggs have a yolk sac - Answer: true _____ are cell clusters that form by the third week of human development. they produce stem cells that migrate into the embryo and colonize the bone marrow, spleen, liver, and thymus. - Answer: blood islands true or false: the liver never stops producing RBCs. - Answer: false; it stops producing RBCs around the time of birth true or false: the spleen stops producing RBCs, but continues to make lymphocytes for life. - Answer: true true or false: the red bone marrow produces all seven kinds of the formed elements, while lymphocytes also produced in other places - Answer: true Blood formation in the bone marrow and lymphatic organs is called ______ and ________ hemopoiesis - Answer: myeloid and lymphoid ____ is where all formed elements originate. It can be classified as multipotent stem cells, but hematologists consider them to be pluripotent stem cells (PPSCs) - Answer: hemopoetic stem cell (HSC) True or false: HSCs multiply to maintain a small but persistent population in the bone marrow, but some of them go on to become a variety of more specialized cells called colony forming units (CFUs) - Answer: true true or false: the blood plasma does not require any replacement - Answer: false where does the blood plasma get most of its water, electrolytes, and organic nutrients - Answer: digestive tract where does the blood plasma get most of gamma globulins - Answer: connective tissue plasma cells and liver what are the two primary functions of the RBCs - Answer: 1. pick up oxygen from the lungs and deliver it to the tissues elsewhere 2. to pick up carbon dioxide from the tissues and unload it into the lungs an ___ is a discoidal cell with a biconcave shape - Answer: erythrocyte true or false : the RBCs do not have a nucleus and other organelles because they lose them during maturation - Answer: true How do RBCs get ATP - Answer: anaerobic fermentation true or false: RBCs are made to consume and transport oxygen - Answer: false; only transport oxygen ____ is the red pigment that gives a RBC its color and name - Answer: hemoglobin what are some functions of hemoglobin - Answer: oxygen transport, aids in CO2 transport and buffering pH _____ are on the outer surface of the RBCs and helps to determine a person's blood type - Answer: glycolipids what are the two cytoskeleton proteins in the RBC that gives the membrane resilience and durability - Answer: spectrin and actin what are the hypotheses on why the RBC is shaped the way it is - Answer: 1. increase surface area for more transfer of oxygen 2. allows it flow better through larger blood vessels hemoglobin consists of four protein chains called _____ - Answer: globins the alpha and beta chains of the hemoglobin form a ____ group which binds oxygen to an iron atom. - Answer: heme how many O2 molecules can one hemoglobin molecule carry - Answer: 4 what type of hemoglobin is in most adults - Answer: HbA (adult hemoglobin ) when the beta chains of hemoglobin are replaced with delta chains what is the name of the hemoglobin - Answer: HbA2 What type of hemoglobin is found in a fetus - Answer: HbF (fetal hemoglobin) what makes the fetal hemoglobin different from the adult - Answer: replaces beta chains with gamma chain what is so beneficial about the fetal hemoglobin if it is the same length as the adult hemoglobin - Answer: HbF binds O2 more tightly ; thus it enables the fetus to extract more O2 from the mothers bloodstream what are the three most common measurements for blood - Answer: hemacrit, hemoglobin concentration and RBC count _____(packed cell volume, PCV) is the percentage of whole blood volume compose of RBCs - Answer: hemacrit _____ is the concentration of hemoglobin in the whole blood - Answer: hemoglobin concentration why do women naturally have lower values for hemacrit, hemoglobin concentration and RBC count - Answer: 1. androgens stimulate RBC production and men have higher androgen levels 2. women of reproductive age have periodic menstral losses 3. hemacrit is inversely proportional to percentage body weight, which is higher in women than men 4. the blood in men clot faster and fewer blood vessels how long does an erythrocyte last - Answer: 120 days erythrocyte production is called ____ - Answer: erythropoiesis how long does it take for erythropoiesis to take place - Answer: 3 to 5 days what are the 4 major developments in erythropoiesis - Answer: a reduction in cell size, an increase in cell number, synthesis of hemoglobin, loss of the nucleus and other organelles what are the stages of erythropoiesis - Answer: hemopoetic stem cell --> erythrocyte colony-forming unit --> erythroblast --> reticulocyte --> erythrocyte what type of receptors to the colony forming unit erythrocytes have - Answer: erythropoietin (EPO) what is erythropoietin - Answer: a hormone secreted from the kidney that stimulates the ECFU to transform into the erythroblast ______ multiply and synthesize hemoglobin. when this task is completed the nucleus shrivels and is discharged from the cell; thereby forming the reticulocyte - Answer: erythroblast true or false: reticulocytes are released into the bloodstream before the erythrocyte is fully formed - Answer: true true or false: women lose more iron per day than men - Answer: true iron is an important component in ______ - Answer: erythropoiesis a protein called ___ is produced by the stomach that binds to ferrous (Fe 2+) and transport it to the small intestine. - Answer: gastroferritin true or false: Ferric (Fe 3+) must be broken down into ferrous before it can be used by the body - Answer: true once ferrous is transported in to small intestine and absorbed into the bloodstream, ferrous binds to a plasma protein called ______. it takes the ferrous to the bone marrow, liver, and other tissues - Answer: transferrin bone marrow uses iron for ____ synthesis - Answer: hemoglobin muscle uses iron to make the oxygen-storage protein called ___- - Answer: myoglobin the liver binds surplus iron to a protein called _____ forming a iron-storage complex called ____ - Answer: apoferritin; ferritin ____ releases Fe2+ into circulation as needed - Answer: ferritin ____ and _____ are needed for erythropoiesis for rapid cell division and DNA synthesis - Answer: vitamin B12 and folic acid ____ and ____ are needed for erythropoiesis because they are cofactors for some enzymes that synthesize hemoglobin - Answer: vitamin C and copper copper is transported in the blood by an alpha globin called _ - Answer: ceruloplasmin The RBC is maintained by which type of feedback - Answer: negative ____ is oxygen deficiency in the blood. - Answer: hypoxemia what happens when the kidneys detects hypoxemia - Answer: the kidneys increase the erythropoietin (EPO) output and 3-4 days later the RBC count raises what are some causes of hypoxemia - Answer: 1. blood loss 2. low level of oxygen in the atmosphere 3. abrupt increase in the body's oxygen consumption true or false: all hypoxemia can be cured by increasing erythropoiesis - Answer: false where do most RBC die - Answer: spleen what happens to the dead RBC - Answer: they are trapped in the spleen, broken up and destroyed _____ is the rupture of RBCs - Answer: hemolysis when a RBC ruptures ____ is released all the empty plasma membrane is left. The membrane fragments are digested by __ in the liver and spleen. - Answer: hemoglobin ; macrophages how is the hemoglobin disposed of when hemolysis takes place - Answer: macrophages separate the heme from the globin. the globin is hydrolyzed into free amino acids. the macrophages remove the iron from the heme and release it into the blood stream, which is then"caught" by transferrin and either used or stored. the macrophages convert the rest of the heme to biliverdin then bilirubin. the bilirubin is then released by the macrophages and binds to albumin in the blood plasma. the liver then removes the bilirubin from the albumin and converts into bile. Then the bile is stored in the gall-bladder. what are the two bile pigments - Answer: biliverdin and bilirubin what color is biliverdin - Answer: green what color is bilirubin - Answer: yellow-green what makes your doo doo brown - Answer: bile is discharged into the small intestine by the gall bladder. Then the bacteria in the small intestine converts the the bile to urobilinogen. what makes your pee yellow - Answer: a hemoglobin called urochrome An excess of RBC is called ___ - Answer: polycythemia ______ is due to cancer of the erythropoietic line of the red bone marrow. it can result in a high RBC count as high as 11 million RBC/ microliter - Answer: primary polycythemia (polycythemia vera) _______ is characterized by RBC counts as high as 6 to 8 million RBC/ microliter. It can result from dehydration causing the RBC to become more concentrated. It can also be caused by smoking, air pollution, emphysema, high altitude, excessive aerobic exercise, and other factors that create a state of hypoxemia. - Answer: secondary polycythemia what are some principal dangers of polycythemia - Answer: increased blood volume, pressure, and viscosity chronic polycythemia can lead to embolism, stroke, or heart failure. True or false - Answer: true what are the three categories of anemia - Answer: 1. inadequate erythropoiesis or hemoglobin synthesis 2. hemorrhagic anemia from bleeding 3. hemolytic anemia from RBC destruction true or false: erythropoiesis declines with age - Answer: true _____ is nutritional anemia. it is caused by blood loss without sufficiently compensatory iron ingestion - Answer: iron-deficiency anemia _____ deficiency is rare because it is abundant in meats, but mostly strict vegetarians suffer from this. this deficiency occurs when glands of the stomach fail to produce a substance called intrinsic factor. - Answer: B12 ____ factor is used by the small intestine in order to absorb vitamins - Answer: intrinsic elderly people sometimes develop _____ , which is an autoimmune disease in which the antibodies destroy stomach tissue. it can also be hereditary. - Answer: pernicious anemia _____ anemia is caused by a decline in erythropoiesis, whereas the complete failure or destruction of the myeloid tissue produces ____ anemia, a complete cessation of eyrthropoiesis - Answer: hypoplastic; aplastic _____ anemia can lead to the blackening of the skin and grotesque tissue. - Answer: aplastic what are the three main potential consequences of anemia - Answer: hypoxia, blood osmolarity is reduced, and blood viscosity is reduced _____ is a hereditary disease that is caused by a recessive allele that modifies the hemoglobin. these disease is caused by a mutation on the sixth amino acid on the beta chain. gluramic acid is replaced with valine. - Answer: sickle cell disease sickled erythrocytes are sticky which makes them more easy to clump or _______. this causes small blood vessels to be blocked and cause intense pain. - Answer: agglutinate what is evolutionary reason behind sickle cell - Answer: to be resistant against malaria blood types are based on large molecules called ____ and ____ - Answer: antigens and antibodies ____ are complex molecules such as proteins, glycoproteins, and glycolipids that are genetically unique to each individual. They occur on the surface of all cells . - Answer: antigens when a foreign antigen is introduced to the body, it activates an immune response. this allows for antibodies to be produced. true or false - Answer: true ______ bind to antigens and mark them, or the cells bearing them, for destruction. - Answer: antibodies what is agglutination in relation to the immune system - Answer: each antibody molecule binds to two or more antigen molecules and sticks them together blood types result from reactions between antigens called _____ on the surfaces of the RBC and antibodies called _____ in the blood plasma. - Answer: agglutinogens; agglutinins One's ABO blood type is determined by the heredity presence or absence of antigens ____ and ______ on the RBCs. - Answer: A; B when do antibodies of the ABO group begin to appear in the plasma? when do they reach their maximum concentration - Answer: 2 to 8 months after birth ; between ages 8 to 10 true or false: antibodies of the ABO group react against any A or B antigen except one's own. - Answer: true the antibody that reacts against antigen A is called _____ - Answer: alpha agglutinin or anti-A where is anti-A in the body - Answer: in the plasma of people with type O and B blood the antibody that reacts against antigen B is called ____ - Answer: beta agglutinin or anti-B where is anti-B in the body - Answer: in the plasma of people with type O and type A blood which blood type is the most common - Answer: O which blood type is the rarest - Answer: AB what blood type is called universal recipient - Answer: AB what blood type is the universal donor - Answer: O the body has antigen ___ in order to produce a Rh-positive group - Answer: D the body is lacking antigen ____ in order to produce a Rh-negative group - Answer: D what is hemolytic disease of the newborn (HDN)? - Answer: when a Rh- mother has a Rh+ child, after the birth or miscarriage she develops anti-D antibodies which can affect the her second pregnancy ( use diagram on pg. 688) other blood groups include MN, Duffy, Kell, Kidd, and lewis groups. True or false - Answer: true ______ are white blood cells and help with protection and disease - Answer: leukocytes true or false: Leukocytes differ from erythrocytes because they still have their organelles. - Answer: true all WBCs have lysosomes called _____ in the cytoplasm. - Answer: nonspecific (azurophilic) granules what are the two types of WBCs - Answer: granulocytes and agranulocytes true of false granulocytes have specific granules that help to distinguish each cell type from the other - Answer: true true or false: agranulocytes do not have specific granules - Answer: true what are the three types of granulocytes? - Answer: neutrophils, eosinophils, and basophils __ are the most abundant of WBCs (60-70%). they phagocytize bacteria and release anitbacterial chemicals. - Answer: neutrophils _____ makes up 2-4% of all WBCs. They phagocytize antigen-antibody complexes, allergens, and inflammatory chemicals and release enzymes that weaken or destroy parasites such as worms - Answer: eosinophils _______ makes up less than 0.5% of WBCs. they secrete histamine and heparin - Answer: basophils _____ is a vasodilator that widens the blood vessels, speed the flow of blood to an injured tissue, and makes blood vessels more permeable so that blood components such as neutrophils and clotting proteins can get into connective tissues faster - Answer: histamine ______ is an anticoagulant that inhibits blood clotting and thus promotes the mobility of other WBCs in the area. they secrete signals that attract eosinophils and neutrophils to a site of infection - Answer: heparin what are the two types of agranulocytes? - Answer: lymphocytes and monocytes _______ makes up about 25-33% of WBCs. they destroy cancer cells, cells infected with viruses, and foreign cells, present antigens to activate other cells of immune system, coordinate action of other immune cells, secrete antibodies, and serve in immune memory - Answer: lymphocytes where are medium and large lymphocytes found ? - Answer: fibrous connective tissue and occasionally circulating blood where are small lymphocytes normally found? - Answer: blood film small lymphocytes are sometimes thought to be ___ - Answer: basophils ____ make up about 3-8% of WBCs. they differentiate into macrophages, phagocytize pathogens, dead neutrophils, and debris of dead cells, and they present antigens to activate other cells of immune system. - Answer: monocytes _____ is the production of white blood cells - Answer: leukopoiesis what is the stem cell used in leukopoiesis - Answer: hemopoietic stem cells ____ differentiate into neutrophils, eosinophils, and basophils. - Answer: myeloblasts ______ differentiate into monocytes - Answer: monoblasts _____ differentiate into all lymphocyte types - Answer: lymphoblasts Pus is made up of what - Answer: dead neutrophils read pg 694 - Answer: okay a WBC count below 5000 to 10000 WBCs/ microliter is called ____ - Answer: leukopenia A WBC above 10000 WBCs/ microliter is called ___ - Answer: leukosytosis look at diagram on pg 695 - Answer: okay ____ is cancer of hemopoietic tissues that usually produces an extremely high number of circulating leukocytes and their precursors. - Answer: leukemia what are the two different types of leukemia - Answer: myeloid, lymphoid ____ leukemia is marked by uncontrolled granulocyte production. - Answer: myeloid ____ leukemia involves uncontrolled lymphocyte or monocyte production. - Answer: lymphoid true or false: myeloid and lymphoid leukemia can be chronic and acute - Answer: true ____ leukemia appears suddenly, progresses rapidly and casuses death within a few months if not treated. - Answer: acute _____ leukemia develops slowly and may go undetected for many months. - Answer: chronic ____ is the cessation of bleeding - Answer: hemostasis ____ are not cells but small fragments of marrow cells called megakaryocytes. - Answer: platelets what are some structures within platelets - Answer: lysosomes, mitochondria, microtubles, microfilaments, granules filled with platelet secretions, and an open canalicular system a system of channels within the platelets are called ____ - Answer: open canalicular system true or false: platelets have no nucleus - Answer: true what are 7 functions of platelets - Answer: 1. they secrete vasoconstrictors 2. form platelet plugs to seal breaks in blood vessels 3. they secrete procoagulants (clotting factors) to promote blood clotting te the formation of clot-dissolving enzymes 5. secrete chemicals that attract neutrophils and monocytes to sites of inflammation 6. interalize and destroy bacteria 7. secrete growth factors to stimulate mitosis in fibroblasts and smooth muscle the production of platelets is a called ____ - Answer: thrombopoiesis Hemopoietic stem cells produce receptors for the hormone _____, from liver and kidneys, and become megakaryoblasts. - Answer: thrombopoietin ___ is a gigantic cell, visible to the naked eye, with a huge multilobed nucleus and multiple sets of chromosomes. - Answer: megakaryoblasts where do most megakaryoblast live - Answer: sinusoids in red bone marrow A megakaryoblast sprouts long tendrils called ___ that protrude through the endothelium into the blood of the sinusoid. - Answer: proplatelets when the blood flow shears off the proplatelets what is formed - Answer: platelets anything that interferes with platelet production can produce a dangerous platelet deficiency called ____ - Answer: thrombocytopenia what are the three hemostatic mechanisms - Answer: vascular spasm, platelet plug formation and blood clotting (coagulation) the most immediate protection against blood loss is ____ - Answer: vascular spasm ____ is a prompt constriction of a blood vessels - Answer: vascular spasm how do platelets play a role in vascular spasms - Answer: it releases serotoin in order to initiate vasoconstriction true or false: platelets do not adhere to the endothelium that lines healthy blood vessels and the heart - Answer: true the endothelium of a healthy blood vessel is coated with a platelet repellent called ____ - Answer: prosyacylin when a vessel is broken a mass of platelets come together forming a ____ - Answer: platelet plug ____ is the exocytosis of the cytoplasmic granules of the platelets and release factors that promote hemostasis - Answer: degranulation what three factors are recruited to promote hemostasis during platelet plug formation - Answer: sertonin, ADP, and thromboxane A2 _____ attracts more platelets to the area and stimulates their degranulation - Answer: ADP ____ is an eicosanoid that promotes platelet aggregation, degranulation, and vasoconstriction - Answer: thromboxane A2 platelet formation is an example of what type of feedback - Answer: positive ____ of the blood is the last but most effective defense against bleeding - Answer: coagulation (clotting) what is the first step of coagulation - Answer: convert the plasma protein fibrinogen to fibrin what is the function of fibrin - Answer: a sticky protein that adheres to the walls of the vessels true or false: blood cells and platelets stick to the fibrin - Answer: true what are the two reaction pathways of coagulation - Answer: extrinsic and intrinsic mechanism ____ mechanism is initiated by clotting factors released by the damaged blood vessel and perivascular tissues. - Answer: extrinsic _____ mechanism is initiated by only using clotting factors found in the blood itself. - Answer: intrinsic clotting factors are called ____ - Answer: procoagulants clotting factors result in a series of reactions. This is called a ___ - Answer: reaction cascade know the bottom of chart on page 700 - Answer: okay what is clot retraction - Answer: spinous pseudopods of platelets adhere to strands of fibrin and contract. this pulls on the fibrin threads and draws the edges of the broken vessel together. what growth factor arrives after clot retraction - Answer: platelet-derived growth factor (PDGF) what is the function of the PDGF - Answer: stimulates fibroblasts and smooth muscle cells to multiply and repair damage blood vessel true or false: after tissue repair is complete the clot has to be disposed of - Answer: true ____ is the dissolution of a clot - Answer: fibrinolysis what is the blood clotting cascade order - Answer: factor XII, factor XI, factor IX, factor VIII, factor X, prothrombin activator, thrombin, fibrin factor XII catalyzes the formation of a plasma enzyme called ____ - Answer: kallikrein Kallikrein converts the inactive protein plasminogen to ____ - Answer: plasmin ____ is a fibrin-dissolving enzyme that breaks up the clot - Answer: plasmin thrombin aslo activates plasmin and plasmin indirectly promotes the formation of more kallikrein. This is ___ feedback loop - Answer: positive what are three things that prevent coagulation when it is not needed - Answer: platelet repulsion, dilution, and anticoagulants what formation is suppressed by anticoagulants - Answer: thrombin formation _____ is secreted by the liver, it deactivates thrombin before it can act on fibrinogen. - Answer: antithrombin ___ is secreted by the basophils and mast cells. it interferes with the formation of prothrombin activator, which blocks the action of thrombin of fibrinogen and promotes the action of antithrombin. - Answer: heparin this disease occurs mainly in males and is a family of heredity diseases characterized by deficiencies one clotting or another - Answer: hemophilia lack of clotting factor VIII results in which type of hemophilia - Answer: Classical or A lack of clotting factor IX results in which type of hemophilia - Answer: hemophilia B lack of clotting factor XI is which type of hemophilia - Answer: hemophilia C _____ is the abnormal clotting of blood in an unbroken blood vessel. it is very problematic in old age. - Answer: Thrombosis A _____ is a clot that obstructs a small vessel - Answer: thrombus A piece of a thrombus that breaks loose into the bloodstream is called an ____ - Answer: embolus how can an embolus be dangerous - Answer: it can block blood flow in areteries and cause tissue death tissue death is called ___ - Answer: infraction the disorder of having traveling blood clots is called ___ - Answer: thromboembolism true or false: thrombosis is more likely to occur in the arteries. - Answer: false; veins true or false: thrombosis occurs more in the leg veins - Answer: true what is cardiology - Answer: study of the heart the cardiovascular system consists of what two things - Answer: the heart and blood vessels what are the two divisions of the cardiovascular system - Answer: pulmonary and systemic circuits ____ circuit carries blood to the lungs for gas exchange and returns it to the heart - Answer: pulmonary ___ circuit supplies blood to every organ of the body, including parts of the lungs, and wall of the heart itself - Answer: systemic the ___ side of the heart supplies the pulmonary circuit and the ___ side of the heart supplies the systemic circuit - Answer: right; left the heart lies within a thick partition called the _____ between the two lungs - Answer: mediastinum the heart is enclosed in a double-walled sac called the ____ - Answer: pericaridum two types of paricardium - Answer: visceral and pericaridal(parietal) the outer wall of the pericardium is called the _____.It has a fibrous layer of dense irregular connective tissue and a thin deep serous layer . - Answer: pericardial sac or parietal pericardium the serous layer of pericardial sac turns inward at the base of the heart and the ______ pericardium - Answer: visceral between the parital and visceral membranes of pericaridum is a space called ___ - Answer: pericardial cavity true or false: the heart is in the pericardial cavity - Answer: false: it is enfolded by it the pericardial fluid that is within the pericardial cavity comes from which layer of he pericardial sac - Answer: serous layer what is the purpose of the pericaridal fluid - Answer: lubricates membranes to reduce friction so heart can easily constrict ___ is inflammation of pericardium that causes the membranes of heart to become rough and produce a painful friction rub - Answer: pericarditis what are the three layers of the heart wall - Answer: epicardium, myocardium and endocardium what is another name for the epicaridum - Answer: visceral pericardium ____ is a serous membrane of the external heart surface. - Answer: epicardium what type of epithelium does the epicardium have - Answer: simple squamous of areolar tissue true or false: the epicardium contains some adipose tissue - Answer: true ___ lines the interior of the heart chambers. - Answer: endocardium what type of epithelium does the endocardium have - Answer: simple squamous of areolar tissue true or false: like the epicardium the endocaridum has adipose tissue - Answer: false; does not have adipose tissue _______ is the thickest layer of the heart and performs the work of the heart. - Answer: myocardium the muscles of the myocardium spirals around the heart forming a ___ vortex - Answer: myocardial what is the purpose of the mycardial vortex formation - Answer: when the ventricles contract they exhibit a twisting or wringing motion that enhances the ejection of the blood . ____ are cardiac muscle cells - Answer: cardiocytes what type of fibers make up the fibrous skeleton of the heart - Answer: collagen and elastic fibers what are the functions of the fibrous skeleton - Answer: 1. provides structure for the heart especially around the valves and the openings of the great vessels 2. it anchors the cardiocytes and gives them something to hold on to 3. its a nonconductor that serves as electrical insulation between atria and ventricles 4. may aid in refilling the heart with blood after each beat true or false: the fibrous skeleton holds the valves and openings of the great vessels open and prevents them stretching when blood surges through them - Answer: true why is the insulation of the heart provided by the fibrous skeleton important - Answer: the insulation is important for timing and coordination of electrical and contractile activity what are the four chambers of the heart - Answer: right atrium, right ventricle, left atrium , left ventricle each atrium has a small earlike extension called an ___ that slightly increases the atrium volume - Answer: auricle the ____ sulcus encircles the heart near the base and separates the atria above from the ventricles below - Answer: coronary or atrioventricular the ___ and ___ sulci extend obliquely down the heart from the coronary sulcus toward the apex. there is one in the front and one in the back of the heart - Answer: anterior and posterior interventricular _____ divides the right ventricle form the left - Answer: interventricular septum ____- divides the right and left atria - Answer: interatrial septum true or false: the atria have thin walls because their main purpose is to allow blood to enter and pump to the ventricles. They have a small workload - Answer: true the right atrium and both auricles exhibit internal ridges called _____ muscles - Answer: pectinate the ____ ventricle pumps blood only to the lungs and back to the left atrium, so its walls are moderately muscular. - Answer: right why is the left ventricle the thickest ventricle? - Answer: it has to pump blood through the entire body the internal ridges in the ventricles are called ____ - Answer: trabeculae carneae what is the purpose of the trabeculae carneae - Answer: to keep the ventricular walls from clinging to each other during contraction each valve of the heart consists of two or three fibrous flaps of tissue called ____ - Answer: cusps or leaflets _____ valves regulate the openings between the atria and ventricles. - Answer: atrioventricular (AV) The right AV is called ____ - Answer: tricuspid the left AV is called ____ (2 names) - Answer: mitral or biscuspid _____ connect the valve cusps to conical papillary muscles on the floor of the ventricle - Answer: tendinous cords (chordae tendineae) what is the function of the tendinous cords (chordae tendineae) - Answer: prevents AV valves from flipping inside out or buldgeing into the atria when the ventricles contract what are the two semilunar valves - Answer: pulmonary and aortic valves what is the function of the semilunar valves - Answer: regulate the flow of blood from the ventricles into great arteries The ____ valve controls the opening from the right ventricle into the pulmonary trunk. - Answer: pulmonary the ____ valve controls the opening from the left ventricle into the arota - Answer: aortic true or false: the pulmonary and aortic valves have no tendinous chords - Answer: true if the pulmonary valve and aortic valves do not have tendinous chords then how are they opened - Answer: they are pushed open and closed by changes in blood pressure that occur when the chambers of the heart contract and relax trace a drop of deyoxygenated blood through the heart - Answer: blood enters through superior and inferior vena cava, right atrium, right AV (tricuspid), right ventricle, pulmonary valve, left and right side pulmonary trunk , lungs, left and right pulmonary veins, left atrium , left AV (mitral), left ventricle, aortic valve, aorta the blood vessels of the heart wall constitute the ____ circulation - Answer: coronary The _______ travels through the coronary sulcus under the left auricle and divide into two branches - Answer: left coronary artery (LCA) what are the two branches to the LCA - Answer: anterior interventricular branch and circumflex branch ______ travels down the anterior interventricular sulcus to the apex. it supplies blood to both ventricles and anterior of interventricular septum - Answer: anterior interventicular branch (check) _____ continues around the left side of the heart in the coronary sulcus .it supplies blood to the left atrium and posterior wall of left ventricle. It gives off a left marginal branch that gives blood to the left ventricle. - Answer: circumflex branch the ___ artery supplies the right atrium and sinoatrial node ( pacemaker). it continues along the coronary sulcus under the right auricle and gives off two branches. - Answer: right coronary (RCA) what are the two branches of the right coronary artery - Answer: right marginal branch and posterior interventricular branch ______ runs toward the apex of the heart and supplies the lateral aspect of the right atrium and ventricle - Answer: right marginal branch ______ meets up with the anterior interventricular branch and supplies the posterior wall of both ventricles as well as the posterior portion of the interventricular septum. - Answer: posterior interventricular branch A fatty deposit or blood clot in a coronary artery can cause a ____ or heart attack - Answer: myocardial infraction (MI) The ___ circulation can supply the heart tissue with blood if the primary route becomes obstructed - Answer: collateral true or false: in the heart the blood flow peaks when the ventricles contract and eject blood into the arteries and diminishes when the ventricles relax and fill. - Answer: true true or false: in the coronary arteries the flow peaks when the heart relaxes - Answer: true what are three reasons why the flow in the coronary arteries peaks when the heart relaxes - Answer: 1. contraction of myocardium compresses the coronary arteries and obstructs the blood flow 2. when the ventricles contract, the aortic valve is forced open and the cusps cover the openings of the coronary arteries, blocking the blood flow 3. when the ventricles relax the left over blood surges back toward the heart. it fills the aortic cusps and some flows into the arteries ___ refers to the route by which blood leaves an organ. - Answer: venous drainage about 5 to 10% of the coronary blood empties directly from multiple small ___ veins into the heart chambers, especially the right ventricle. the rest of the blood returns to the right atrium through several different routes - Answer: thebesian what are the four types of routes that the extra blood takes - Answer: the great cardiac vein, posterior interventricular (middle cardiac) vein, left marginal vein, coronary sinus the ____ collects blood from the anterior aspect of the heart as it travels alongside the anterior interventricular artery. it carries blood from the apex towards the coronary sulcus and empties into the coronary sinus - Answer: great cardiac vein the ___ is found in the posterior interventricular sulcus, it collects blood from the posterior aspect of the heart. it also drains into the coronary sinus - Answer: posterior interventricular (middle cardiac) vein the ___ travels from a point near the apex up the left margin and empties into the coronary sinus - Answer: left marginal vein the ____ is a large transverse vein in the coronary sulcus on the posterior side of the heart. it collects blood from all three of the other veins and it empties blood into the right atrium. - Answer: coronary sinus the heart is described as being ___ because it does not depend on nervous system for its rhythm like clams, crabs, and insects. - Answer: autorhythmic describe the cardiocytes/cardiomyocytes - Answer: short, thick, branched cells what structure do muscles have but the cardiac muscle lacks - Answer: terminal cisternae cardiocytes are joined end to end by thick connections called __ - Answer: intercalated discs what are the three distinct structures located in the intercalated discs - Answer: interdigitating folds, mechanical junctions, and electrical junctions ____ folds occur when the plasma membrane at the end of the cell is folded. the folds of adjoining cells interlock with each other and increase the surface area of intercellular contact - Answer: interdigitating what are the two types of mechanical junctions - Answer: fascia adherens and desmosomes the ____ is a broad band in which actin of the thin myofilaments is anchored to the plasma membrane and each cell is linked to the next via transmembrane proteins. - Answer: fascia adherens ____ are patches of mechanical linkage that prevent the contracting cardiocytes from pulling apart. - Answer: desmosomes what is a type of electrical junction - Answer: gap junctions _____ form channels that allow ions to flow from the cytoplasm of one cardiocyte directly into the next. they enable each cardiocyte to electrically stimulate the neighbors. - Answer: gap junctions true or false: you can replace dead muscle fibers in the heart - Answer: false cardiac muscle depends almost exclusively on ___ respiration to make ATP - Answer: aerobic the heart is rich in myoglobin and glycogen. true or false - Answer: true _____ is a short-term source of the oxygen for aerobic respiration - Answer: myglobin ____ is in the heart to store energy - Answer: glycogen true or false: the heart has huge mitochondria. - Answer: true at rest where does the heart get its energy from - Answer: 60% for fatty acids, 35% from glucose , and 5% from ketones, lactic acid, and amino acids the heartbeat is coordinated by a ____ system composed of an internal pacemaker and nervelike conduction pathways through the myocardium. - Answer: cardiac conduction what is the order in which electrical signals fire in the heart - Answer: SA node fires, excitation spreads through atrial myocardium, AV nodes fire, excitation spreads down AV bundle, purkinje fibers distribute excitation through ventricular myocardium ____ is a patch of modified cardiocytes in the right atrium. This is the pacemaker that initiates the heartbeat and determines heart rate - Answer: sinoatrial node (SA) _____ is located at the lower end of the ineratrial septum near the right AV valve this node acts as an electrical gateway to the ventricles; the fibrous skeleton acts as an insulator to prevent currents from getting to the ventricles by another route. - Answer: atrioventricular (AV) node the ___ bundle is the pathway by which signals leave the AV node. the bundle soon forks into right and left bundle branches, which enter the interventricular septum and descend towards the apex. - Answer: atrioventricualr ___ are nervelike processes that arise from the lower end of the bundle branches. they distribute the electrical excitation to the cardiocytes of the ventricles. - Answer: purkinje fibers what two systems modify the heart rate and contraction strength of the heart - Answer: sympathetic and parasympathetic _______ system speeds of the heart rate and the ___system lowers the heart rate - Answer: sympathetic ; parasympathetic read how the sympathetic and parasympathetic pathways work pg 722 - Answer: okay contraction of the heart is called ____ - Answer: systole relaxation of the heart is called ___ - Answer: diastole the normal heartbeat triggered by the SA node is called the ____ rhythm - Answer: sinus any region of spontaneous firing other than the SA node is called the ___ focus - Answer: ectopic what is the purpose of the etopic focus - Answer: it takes over the heart rhythm when the SA node is damaged the most common etopic focus is the AV node, which produces a slower heartbeat of 40 to 50 bpm called a ____ rhythm. - Answer: nodal the nodal rhythm is insufficient to sustain life if SA or AV node is not functioning. what has to be put into the heart - Answer: a pacemaker why does the SA node spontaneously fire at regular intervals? - Answer: the SA node does not have a stable resting membrane potential. The membrane potential of the heart starts at about -60mV and drifts upward, showing a gradual depolarization called the ___ potential - Answer: pacemaker what trickles into the cells of the heart, thereby depolarizing the RMP of the cells of the SA node - Answer: Na+ true or false: as the Na+ slowly comes in K+ goes out - Answer: false; K+ does not leave what happens when the pacemaker potential reaches a threshold of -40mV - Answer: voltage-gated calcium channels open and Ca 2+ flows in from the extracellular fluid. true or false: as calcium comes into the cells sodium is also still seeping in - Answer: true once the action potential has reached its peak, what ion begins to flow out - Answer: K+ true or false: each depolarization of the SA node sets off a heartbeat - Answer: true look at picture on pg 724 to understand the action potential of the cardiocytes - Answer: okay why does the cardiac muscle have a longer absolute refractory period than the skeletal muscles - Answer: the long refractory period prevents wave summation and tetanus, which would stop the pumping action of the heart what instrument can be used to detect electrical currents of the heart - Answer: electrocardiograph ____ is a chart formed by a electrocardiograph - Answer: electrocardiogram (ECG or EKG) true or false: An ECG is a composite recording of all action potentials produced by the nodal and myocardial cells. - Answer: true what are the 3 components of the EKG - Answer: P wave, QRS complex, T wave The ___ is produced when a signal form the SA node spreads through the atria and depolarizes them - Answer: P wave the ___ consists of a small downward deflection, a tall sharp peak, and a final downward deflection. It is formed when the signal from the AV node spreads to the ventricular myocardium. - Answer: QRS complex The QRS complex is mainly a depiction of the depolarization of the ___ - Answer: ventricles what creates the complex shape in the QRS complex - Answer: the different sizes of the ventricles the ___ is generated by ventricular repolarization immediately before diastole - Answer: T wave true or false: the ventricles that longer to repolarize than depolarize - Answer: true true or false : an EKG can help to detect abnormalties is in heart rhythm - Answer: true SA node-driven sinus rhythm of the heartbeat is called an ___ - Answer: arrhythmia ____ is the hallmark of a heart attack (myocardial infraction) - Answer: ventricular fibrillation ____ is the cessation of cardiac output, with the ventricles either motionless or in fibrillation - Answer: cardiac arrest ____ is an emergency procedure in which the heart is given a strong electrical shock with a pair of electrodes - Answer: defilbrillation ____ is the sounds of the heart - Answer: auscultation which heart sounds make the lub-dub noise - Answer: first and second heart sounds (S1 and S2) ___ is the louder and longer heart sound - Answer: S1 ___ is the softer and sharper heart sound - Answer: S2 In whom is the a third (S3) heart sound found - Answer: in children and adolescents what is it called when one has an S3 sound - Answer: gallop or triple rhythm what are the 4 stages of the cardiac cycle - Answer: ventricular filling, isovolumetric contraction, ventricular ejection, isovolumetric relaxation ___ occurs during diastole. the ventricles expand causing their pressure to drop lower of that of the atria. As a result the AV valve open and blood flows into ventricles causing the ventricular pressure to rise and atrial pressure to fall - Answer: ventricular filling what are the three phases of the ventricular filling - Answer: 1. rapid ventricular filling 2. diastasis 3. atrial systole ____ is when blood enters very quickly . it is a part of the ventricular filling phase of cardiac cycle - Answer: rapid ventricular filling ____ slower filling of ventricle. The P wave occurs at the end of this, therefore marking the depolarization of the atria - Answer: diastasis _____ completes the filling process - Answer: atrial systole ___ occurs in the cardiac cycle in which the atria repolarize, relax and remain in diastole for the rest of the cardiac cycle. The ventricles depolarize, generating the QRS complex, and begin to contract. AV valves close and one is able to hear the S1 heart sound - Answer: isovolumetric contraction * key note on pg 731 about isovolumetric contraction - Answer: okay _______ is the ejection of blood begins when ventricular pressure exceeds arterial pressure and forces the semilunar valves open. - Answer: ventricular ejection true or false: the ventricles expel all their blood - Answer: false; they do not expel all their blood ____ volume is volume that the ventricle ejects - Answer: stroke (SV) ____ is the percentage volume ejected by ventricle - Answer: ejection fraction ____ is the blood remains behind in the ventricles - Answer: end-systolic volume (ESV) with exercise what happens to the ejection volume - Answer: increases _______ is early ventricular diastole, when the T wave ends and ventricles begin to expand. At the beginning of diastole the blood from the aorta and pulmonary trunk briefly flows backward through the semilunar valves. - Answer: isovolumetric relaxation briefly read a note a about isovolumetric relaxation of pg 731 - Answer: okay true or false: equal output by the two ventricles is essential to homeostasis - Answer: true what will happen if the right ventricle pumps more blood into the lungs than the left ventricle can handle on return ? - Answer: blood will accumulate in the lungs causing pulmonary hypertension, edema, and a risk of drowning in ones own blood what will happen if the left ventricle pumps more blood than the right - Answer: blood accumulates in systemic circuit causing hypertension and widespread systemic edema ___ is a pooling of fluid in the abdominal cavity - Answer: ascites fluid accumulation in either circuit due to insufficiency of ventricular pumping is called _____ - Answer: congestive heart failure (CHF) what are common causes of congestive heart failure - Answer: myocardial infraction, chronic hypertension, valvular defects, and congenital defects in cardiac anatomy ____ is a persistent, resting adult heart rate above 100bpm. It can be caused by stress, anxiety, stimulants, heart disease, or fever. - Answer: tachycardia _____ is a persistent, resting adult heart rate below 60 bpm. it is common during sleep and in endurance training of athletes. - Answer: Bradycardia how does endurance training affect the heart - Answer: enlarges the heart and increases the stroke volume ____ chronotropic agents are factors that raise the heart rate. - Answer: positive ___ chronotropic agents are factors that lower the heart rate. - Answer: negative ____ are in the muscles and joints to provide information of changes in physical activity - Answer: proprioceptors ____ are pressure sensors in the aorta and internal carotid arteries. they send a continuous stream of signals to the medulla. - Answer: baroreceptors (pressoreceptors) _____ occur in the aortic arch, carotid arteries, and medulla. they are sensitive to blood pH, Carbon dioxide, and oxygen levels . they are more important in respiratory control than in cardiovascular control - Answer: chemoreceptors go over pages 736-37 - Answer: okay What are the three principal categories of blood vessels? - Answer: arteries, veins, and capillaries _______ are the efferent vessels of the cardiovascular system. - Answer: arteries Efferent vessels take blood (to/away from) the heart. Afferent vessels take blood (to/away from) the heart. - Answer: away from; to _______ are the afferent vessels that carry blood back to the heart. - Answer: veins _______ are microscopic, thin-walled that connect the smallest arteries to the smallest veins. - Answer: capillaries T/F: Capillaries, veins, and arteries differ in location, direction of blood flow, and histology. - Answer: True The walls of arteries and veins are composed of three layers called _______. - Answer: tunics What are the names of the three tunics? - Answer: tunica interna (tunica intima), tunic media, and tunica externa (tunic adventitia) The ________ lines the inside of the vessel and is exposed to the blood. - Answer: tunica interna (tunica intima) The tunica interna consists of a simple squamous epithelium called ________ overlying a basement membrane and a sparse layer of loose connective tiisue; it is continous with the myocardium. - Answer: endothelium What are the functions of the endothelium? - Answer: it acts as a selectivity permeable barrier to materials entering or leaving bloodstream, it secretes chemicals that stimulate dilation or constriction of the vessel, and it normally repels blood cells and platelets so that they flow freely without sticking to the wall What happens when the endothelium is damaged? - Answer: Platelets may adhere to it and cause a blood clot What happens when the tissue around a vein is inflamed? - Answer: endothelial cells produce cell-adhesion molecules that induce leukocytes to adhere to the surface The _________, the middle layer, is usually the thickest. - Answer: tunica media What is the function of the tunica media? - Answer: it strengthens vessels, prevents blood pressure from rupturing them, and regulates the diameter of a blood vessel. The ________ is the outermost layer. It consists of loose connective tissue that often merges with that of neighboring blood vessels, nerves, or other organs. - Answer: tunica externa (tunic adventitia) ____ are small vessels that nourish the outer half of a larger vessel - Answer: vasa vasorum ________ are sometimes called the resistance vessels of the cardiovascular system because they have a relatively strong, resilient tissue structure. - Answer: Arteries Which is more muscular - veins or arteries? - Answer: arteries What are the three categories of arteries in order from biggest to smallest? - Answer: Conducting (elastic), distributing (muscular), and resistance. (CDR) Examples of _________ arteries are aorta, common carotid and subclavian arteries, pulmonary trunk, and common iliac arteries . - Answer: conducting (elastic or large) Give some examples of conducting arteries - Answer: aorta, common carotid and subclavian arteries, pulmonary trunk, and common iliac arteries What is the layer of elastic tissue in conducting arteries between the interna and media called? - Answer: internal elastic lamina T/F: The tunica media of conducting arteries consists of 40-70 layers of elastic sheets, perforated like slices of Swiss cheese, alternating with thin layers of smooth muscle, collagen, and elastic fibers. - Answer: True What is the layer of elastic tissue in conducting arteries between the externa and media called? - Answer: external elastic lamina Conducting arteries ______ as they receive blood during ventricular systole and ______ during diastole. - Answer: expand; recoil Why do arteries recoil between heart beats? - Answer: to keep the blood pressure from dropping too low while the heart is relaxing and refilling Arteries stiffen with age, a condition known as _______. Since this causes the artery to become less able to expand and recoil freely there are risks that the artery might develop a(n) ___________. - Answer: arteriosclerosis; aneurysm __________ arteries are smaller branches that distribute blood to specific organs. - Answer: distributing (muscular or medium) _________ arteries are usually too variable in number and location to be given individual names. They exhibit up to 25 layers of smooth muscle and relatively little elastic tissue. - Answer: resistance (small) The smallest of the arteries, up to 200 um in diameter and with only one to three layers of smooth muscle, are called _________. They have little tunica externa. They are major point of control over how much an organ or tissue receives. - Answer: arterioles ____ are short vessels that link arterioles to capillaries to provide shortcuts through which blood can bypass the capillaries and flow directly to a venule - Answer: metarterioles What are the three types of receptors found on the major arteries above the heart? - Answer: carotid sinuses, carotid bodies, and aortic bodies. _______ are baroceptors, or pressure sensors, that monitor blood pressure. - Answer: Carotid sinuses _______ are oval receptors that are innervated by senory fibers of the glossopharyngeal nerves. They are chemoreceptors that transmit signals to the brainstem respiratory centers, which adjust breathing to stabalize the blood pH and it's Co2/O2 levels. - Answer: carotid bodies ________ are structurally similar to carotid bodies and have the same function, but transmit their signals to the brainstem via vagus nerves. - Answer: aortic bodies What are the two places that nutrients, wastes,hormones, and leukocytes pass through the walls of vessels? - Answer: capillaries and some venules Capillaries are sometimes referred to as the ________ vessels of the cardiovasuclar system. The artierioles , capillaries, and venules are also called _________. - Answer: exhange; microvasculature (microcirculation) What are the three types of capillaries? - Answer: continuous, fenestrated, and sinusoids __________ occur in most tissues, such as skeletal muscles. Their epithelial cells, held together by tight junctions, form a continuous tube. - Answer: continous capillaries A thin, protein like layer, the _______ _______, surrounds the endothelium and separates it from the connective tissues. - Answer: basal lamina The endothelial cells are separated by narrow _______ clefts. - Answer: intercellular Some continuous capillaries contain ________. They have elongated tendrils that wrap around the capillary. - Answer: pericytes ________ have endothelial cells riddled with patches of filtration pores. - Answer: fenestrated ______ are often spanned by a glycoprotein membrane that is much thinner than the cell's plasma membrane. They allow for the passage of small molecules, but still retain most proteins and larger particles in the blood stream. - Answer: filtration pores (fenestrations) _______ are important in organs that engage in rapid absorption or filtration. (ex. kidneys, endrocrine glands, small intestine and choroid plexuses of the brain) - Answer: fenstrated capillaries ________ are irregular blood-filled spaces in the liver, bone marrow, spleen, and some other organs. They are twisted and conform to the shape of the surrounding tissue. - Answer: Sinusoids (discontinuous) Capillaries are organized into weblike networks called ________ ____. - Answer: capillary beds T/F: At any given time, about 3/4 of the body's capillaries are shut down because there isn't enough blood to supply all of them at once. - Answer: True There is often a single smooth muscle cell that wraps like a cuff around the opening to each capillary acting like a ____________, regulating blood flow. - Answer: precapillary sphincter List the order of blood flow from the smallest to largest veins - Answer: postcapillary venules, muscular venules, medium veins, venous sinuses, and large veins _______ are the smallest of the veins, beginning with diameters of about 10 to 20 um. They receive blood from capillaries directly or by way of the distal ends of the thoroughfare channels. - Answer: postcapillary venules _______ receive blood from the postcapillary venules. They are often up to 1 mm in diameter. - Answer: muscular venules _______ range up to 10 mm in diameter. Most veins with individual names are in this category (such as radial and ulnar veins and great saphenous veins). - Answer: medium veins Many medium veins exhibit infoldings of the tunica interna that meet in the middle of the lumen, forming ____________ directed towards the heart. - Answer: venous valves ________ are veins with especially thins walls, large lumens, and no smooth muscle. They are not capable of vasoconstriction. - Answer: Venous sinuses What are examples of venous sinuses veins? - Answer: coronary sinus of heart and dural sinuses of brain _____ have diameters greater than 10 mm. they have smooth muscles in all 3 tunics. Examples are the venae cavae, pulmonary veins, internal jugular veins, and renal veins - Answer: large veins List the simplest, most common route of blood flow - Answer: heart → arteries → capillaries → veins → heart In a ____________ the blood flows through two consecutive capillary networks before returning to the heart. - Answer: portal system Where do portal systems occur? - Answer: kidneys, connecting the hypothalumus to the anterior pituitary, and connecting the intestines to the liver. An _______ is a point of convergence between two blood vessels other than capillaries. - Answer: anastomosis In an ________ __________ blood flows from an artery directly into a vein and bypasses the capillaries. - Answer: arteriovenous anastomosis (shunt) Where do shunts occur? - Answer: Fingers, palms, toes, and ears. ______ are the most common anastomoses. This is when one veins empties directly into another. - Answer: venous T/F: Blockage of a vein is rarely as life-threatening as an artery. - Answer: true _______ anastomoses is where two arteries merge and provide collateral routes of blood supply to a tissue. - Answer: arterial _____ is the amount of blood flowing through an organ, tissue, or blood vessel in a given time. - Answer: flow _______ is the flow per given volume or mass of tissue. - Answer: Perfusion ______ is the physical principles of blood flow, which are mainly on pressure and resistance. - Answer: hemodynamics ________ is the force that the blood exerts against a vessel wall. - Answer: blood pressure _______ pressure is the peak arter