Biology 116 Chapters 17 and 18 Learning Outcomes

Describe the functional aspects of RBCs.

(1) large surface area-to-volume ratio that results in a faster exchange of materials between the RBC and its surroundings. (2) the ability to form stacks of cells. (3) flexibility, which allows RBCs to bend and pass through capillaries that are narrower than their diameter.

Define end-diastolic volume (EDV) and end systolic volume (ESV).

(EDV) is the amount of blood a ventricle contains at the end of diastole, just before a contraction begins; the end-systolic volume (ESV) is the amount of blood that remains in the ventricle at the end of ventricular systole.

What are the functions of blood?

(TTRRD) 1. Transport dissolved gasses, nutrients, hormones and metabolic wastes. 2. Temperature regulation. 3. Regulation of pH and ion composition in interstitial fluid. 4. Restrict fluid loss at injury sites. 5. Defend against toxins and pathogens.

How to basophils respond to tissue damage?

Basophils enter damaged tissues and release a variety of chemicals, including histamine, which promotes inflammation.

In what way would a liver disease affect the level of bilirubin in the blood?

Bilirubin would accumulate in the blood, producing jaundice, because diseases that damage the liver impair the liver's ability to excrete bilirubin in the bile

Compare bradycardia and tachycardia.

Bradycardia is a heart rate below 60 beats per minute and tachycardia is a heart rate above 100 beats per minute.

Why does tetany not occur in cardiac muscle?

Cardiac muscle has a long refractory period that continues until relaxation is well under way. As a result, another action potential cannot arrive quickly enough for summation to occur, and thus tetany cannot occur.

Why is it important that cardiac tissue contain many mitochondria and capillaries?

Cardiac tissue is metabolically active and dependent on mitochondrial activity for ATP and local capillaries for obtaining oxygen and nutrients.

Why is it important for impulses from the atria to be delayed at the AV node before they pass into the ventricles?

If the impulses from the atria were not delayed at the AV node, they would be conducted through the ventricles so quickly by the bundle branches and Purkinje cells that the ventricles would begin contracting before the atria had finished contracting. As a result, the ventricles would not be as full of blood as they could be, and the pumping action of the heart would be less efficient

Which specific plasma proteins would you expect to be elevated during an infection?

immunoglobulins (antibodies) in the blood.

What do semilunar valves prevent?

prevent the backflow of blood into the ventricles.

List the three stages of an action potential in a cardiac muscle cell.

rapid depolarization, plateau, and repolarization

Name the four chambers of the heart.

right atrium, left atrium, right ventricle, left ventricle

Describe the heart's location in the body.

surrounded by the pericardium in the anterior mediastinum, deep to the sternum and superior to the diaphragm.

Define autorhythmicity.

the ability of the heart to contract without neural or hormonal stimulation.

Define cardiac regurgitation.

the abnormal backflow of blood into the atria when the ventricles contract, and it is prevented by the chordae tendineae and papillary muscles.

Why can cardiac tamponade be a life-threatening condition?

the accumulating fluid within the pericardial cavity restricts heart movement.

If the cells of the SA node failed to function, how would the heart rate be affected?

the heart would continue to beat, but at a slower rate; the AV node would act as the pacemaker.

Define mediastinum.

the mass of connective tissue between the two pleural cavities that contains the heart, along with the great vessels (large arteries and veins attached to the heart), thymus, esophagus, and trachea

Define cardiac cycle.

the period between the start of one heartbeat and the beginning of the next

The anterior view of the heart is dominated by which chambers? The posterior?

the right atrium and right ventricle

Define hemostasis.

the stopping of bleeding. It involves three phases: the vascular phase, the platelet phase, and the coagulation phase.

What is hematology?

the study of blood and its components, fluids and cells. Also includes the study of blood forming organs and blood disorders

Why is ventricular fibrillation fatal?

the ventricles merely quiver and do not pump blood into the systemic circulation.

Describe the purpose of a stent.

wire-mesh tubes that prop open the natural blood vessel, creating a channel to restore blood flow. Without adequate blood flow to the cardiac muscle, the tissue would die.

Which condition would a patient have if she had a depressed hematocrit level?

anemia.

List the phases of the cardiac cycle.

atrial systole, atrial diastole, ventricular systole, ventricular diastole

Describe platelets and their origin.

cell fragments that develop from megakaryocytes. These large cells shed their cytoplasm in small, membrane-enclosed packets. These packets are the platelets that enter the bloodstream.

Briefly describe the vascular, platelet, and coagulation phases of hemostasis.

- During the vascular phase, local blood vessel constriction (vascular spasm) occurs at the injury site. -In the platelet phase, platelets are activated, aggregate at the site, and adhere to damaged blood vessel surfaces. -In the coagulation phase, factors released by platelets and endothelial cells interact with clotting factors (through either the extrinsic pathway, the intrinsic pathway, or the common pathway) to form a blood clot, a process involving the conversion of soluble fibrinogen to insoluble fibers of fibrin.

List the important features of the ECG and indicate what each represents (draw it out).

-the P wave (atrial depolarization) -the QRS complex (ventricular depolarization) -the T wave (ventricular repolarization).

Why can't a person with type A blood safely receive blood from a person with type B blood?

A person with type A blood also has anti-B antibodies, so if the person received a transfusion of type B blood, the transfused red blood cells would clump, or agglutinate, potentially blocking blood flow to various organs and tissues.

Does an Rh+ mother carrying an Rh- fetus require a RhoGAM injection? Explain your answer.

An Rh+ mother carrying an Rh− fetus does not require a RhoGAM injection because the fetus is not at risk of Rh incompatibility. The fetus is not at risk because its RBCs lack Rh surface antigens, and the mother's plasma lacks anti-Rh antibodies.

What affect would an increase in sympathetic stimulation of the heart have on the end-systolic volume (ESV)?

An increase in sympathetic stimulation of the heart would increase heart rate and force of contraction. The end-systolic volume (ESV) is the amount of blood that remains in a ventricle after a contraction (systole). The more forcefully the heart contracts, the more blood it ejects. Therefore, increased sympathetic stimulation results in a lower ESV.

What effect would an increase in venous return have on stroke volume?

An increase in venous return would stretch the heart muscle. The more the heart muscle is stretched, the more forcefully it will contract (to a point). The more forceful the contraction, the more blood the heart will eject with each beat (stroke volume). Therefore, increased venous return would increase the stroke volume (if all other factors are constant).

Which type of white blood cell would you find in the greatest number in an infected cut?

An infected cut would contain a large number of neutrophils, phagocytic white blood cells that are generally the first to arrive at the site of an injury.

List the arteries and veins of the heart.

Arteries: left coronary artery, anterior inter ventricular artery, right coronary artery, marginal arteries, circumflex artery, and posterior interventricular artery. Veins: great cardiac vein, anterior cardiac veins, posterior cardiac vein, middle cardiac vein, and small cardiac vein

Compare arteriosclerosis and atherosclerosis.

Arteriosclerosis is any thickening and toughening of arterial walls; atherosclerosis is a type of arteriosclerosis characterized by changes in the endothelial lining and the formation of fatty deposits (plaque) in the tunica media.

Describe the events that follow the coagulation phase.

Clot retraction and fibrinolysis follow the coagulation phase. The clot consists of fibrin, red blood cells, and platelets. The platelets contract, and the entire clot retracts, pulling the cut vessel edges together. As repairs continue, the clot dissolves through the process of fibrinolysis. Fibrinolysis is activated by plasminogen, which, in turn, activates plasmin, which erodes the foundation of the clot

Which structures collect blood from the myocardium and into which heart chamber does this blood flow?

Coronary veins collect blood from the myocardium and carry it to the right atrium

Damage to the semilunar valve on the right side of the heart would affect blood flow to which vessel?

Damage to the semilunar valve on the right side of the heart would affect blood flow to the pulmonary trunk.

Compare the volume of blood each circuit receives from the contraction of ventricles.

Each circuit receives the same volume of blood from contraction of the ventricles.

Define hemocytoblasts

Form from hematopoietic stem cells and divide in the red bone marrow, producing two types of cells: lympoid stem cells and myeloid stem cells.

Explain why venipuncture is a common clinical procedure for obtaining blood.

In venipuncture, blood is collected from a superficial vein. Venipuncture is a common clinical procedure because superficial veins are easy to locate, the walls of veins are thinner than comparably sized arteries, and blood pressure in the venous system is relatively low, so the puncture wound seals quickly.

Compare the types of cells that lymphoid stem cells and myeloid stem cells produce.

Lymphoid stem cells originate in red bone marrow and give rise to lymphocytes; these stem cells also produce lymphocytes in the thymus, spleen, and lymph nodes. Myeloid stem cells are cells in red bone marrow that give rise to all the formed elements except lymphocytes.

Identify the two types of leukemia.

Myeloid leukemia and lymphoid leukemia

Is the heart always pumping blood when pressure in the left ventricle is rising? Explain.

No. When pressure in the left ventricle first rises, the heart is contracting, but blood is not leaving the heart. During this initial phase of contraction, called the period of isovolumetric contraction, both the AV valves and the semilunar valves are closed. The increase in pressure is the result of the cardiac muscle contracting. When the pressure in the ventricle exceeds that in the aorta, the aortic semilunar valves are forced open, and blood is rapidly ejected from the ventricle

What is the most common blood type in the United States?

O+

Which blood type(s) can safely be transfused into a person with O- blood?

Only type O− blood

Compare oxyhemoblogin with deoxyhemoglobin.

Oxyhemoglobin is hemoglobin whose iron has bound oxygen; it is bright red. Deoxyhemoglobin is hemoglobin whose iron has not bound oxygen; it is dark red.

Compare pernicious anemia with iron deficiency anemia.

Pernicious anemia is insufficient red blood cell production that results from a lack of vitamin B12 ; the blood cells that do develop tend to be macrocytic (abnormally large) and abnormally shaped. Iron deficiency anemia results when the dietary intake or absorption of iron is insufficient, impairing normal hemoglobin synthesis; these blood cells are microcytic (abnormally small).

Identify the two components making up whole blood and list the composition of each.

Plasma: albumins, globulins, fibrinogen, electrolytes, organic nutrients, and organic wastes. Formed elements: which are platelets, white blood cells, and red blood cells. White blood cells include neutrophils, eosinophils, basophils, lymphocytes, and monocytes.

Describe the structural and functional roles of the cardiac skeleton.

Structurally, the cardiac skeleton stabilizes the positions of the heart valves and ventricular muscle cells; functionally, it electrically isolates the atrial and ventricular myocardia

What is determined by the surface antigens on RBCs?

Surface antigens on RBCs are glycoproteins in the plasma membrane; they determine blood type

Compare the anterior cardiac veins to the posterior vein of the left ventricle.

The anterior cardiac veins drain the anterior surface of the right ventricle and empty into the right atrium; the posterior vein of left ventricle drains the area (posterior surface of the left ventricle) supplied by the circumflex artery.

Name and describe the shallow depressions and grooves found on the heart's external surface?

The anterior interventricular sulcus marks the boundary between the left and right ventricles on the heart's anterior surface; the shallower posterior interventricular sulcus marks the boundary between the left and right ventricles on the posterior surface; and the coronary sulcus is a deep groove that marks the border between the atria and the ventricles.

Compare the base of the heart with the apex.

The base of the heart lies at the superior border. The largest veins and arteries of the heart are attached to the base. The apex is located on the inferior aspect of the heart.

Describe the sites and actions of the cardioinhibitory and cardio acceleratory centers.

The cardioacceleratory center in the medulla oblongata activates sympathetic neurons to increase heart rate; the cardioinhibitory center (also in the medulla oblongata) controls the parasympathetic neurons that slow heart rate.

Why is RhoGAM administered to pregnant Rh- women?

When RhoGAM (which contains anti-Rh antibodies) is injected into a pregnant Rh- woman, the anti-Rh antibodies circulate in the mother's bloodstream, where they destroy any fetal RBCs there. This prevents the mother's immune system from making antibodies against the developing fetus's red blood cells.

Why is the left ventricle more muscular than the right ventricle?

The more muscular left ventricle must generate enough force to propel blood throughout the body in the systemic circuit, whereas the right ventricle must generate only enough force to propel blood the short distance to and from the lungs in the pulmonary circuit.

Define hematocrit

The packed cell volume. It's the percentage of whole blood volume contributed by formed elements.

Describe the areas of the heart supplied by the right and left coronary arteries?

The right coronary artery supplies blood to the right atrium, portions of both ventricles, and the conducting system of the heart. The left coronary artery supplies blood to the left ventricle, left atrium, and interventricular septum.

Define hemolytic disease of the newborn (HDN).

a condition in which maternal antibodies attack and destroy fetal red blood cells, resulting in fetal anemia; it occurs in a sensitized Rh- mother who is carrying an Rh+ fetus

What is coronary ischemia?

a condition in which the blood supply of the coronary arteries is reduced.

Define heart failure.

a condition in which the heart can no longer meet the oxygen and nutrient demands of peripheral tissues.

Describe a complete blood count (CBC).

a diagnostic blood test used to determine underlying medical conditions. A CBC includes the RBC count, WBC count, erythrocyte indices (such as hemoglobin content), hematocrit, platelet count, and WBC differential count.

Describe the tissue layers of the pericardium.

a fibrous pericardium and two-layered serous pericardium. The parietal layer of the serous pericardium lines the outer wall of the pericardial cavity. A mesothelium lines the pericardial cavity, and an underlying layer of areolar tissue is in contact with the fibrous tissue of the fibrous pericardium. The visceral layer of the serous pericardium has an outer mesothelium and an underlying layer of areolar tissue that attaches directly to the myocardium.

Describe hemoglobin

a protein composed of four globular subunits, each bound to a heme molecule, which gives red blood cells the ability to transport oxygen in the blood.

Define electrocardiogram.

a recording of the electrical activities of the heart over time.

Describe what happens to blood flow in elastic rebound.

blood in the aorta is driven forward into the systemic circuit, and some is forced back toward the left ventricle and into the coronary arteries.

Caffeine has effects on conducting cells and contractile cells similar to NE. What effect would drinking large amounts of caffeine have on the heart rate?

caffeine acts directly on the conducting system and contractile cells of the heart, increasing the rate at which they depolarize. Drinking large amounts of caffeinated beverages would therefore increase the heart rate

Identify the components of the cardiovascular system

heart blood vessels (arteries, capillaries, and veins) blood

Give the alternate terms for heart contraction and relaxation.

heart contraction: systole heart relaxation: diastole

What are the two phases of ventricular systole?

isovolumetric contraction and ventricular ejection

Describe the location and the position of the heart.

near the anterior chest wall, directly behind the sternum.

Identify the five types of white blood cells.

neutrophils, eosinophils, basophils, monocytes, lymphocytes

From superficial to deep, name the layers of the heart wall.

pericardium, myocardium, and endocardium.