Anatomy & Physiology Chapter 18

a person with blood type A has a. anti- B antibodies in her blood plasma b. anti-A antibodies in her blood plasma c. both anti-A and anti-B antibodies in her blood plasma d. no antibodies in her blood plasma

A

during the recycling of components following the normal destruction of erythrocytes, globin is broken down, and its components are a. used to synthesize new proteins b. stored as iron in the liver c. eliminated from the body in the bile d. removed in the urine

A

a clot is best described as a. an aggregation of platelets b. a fibrin network with trapped formed elements c. agglutination of erythrocytes d. all of these are correct

B

in an adult, the stem cells for leukocytes reside in the a. blood b. red bone marrow c. liver d. muscle

B

the hematocrit is a measure of a. water concentration in the plasma b. the percentage of formed elements in the blood c. the number of platelets in the blood d. antibody concentration in the plasma

B

which cell type forms platelets in the red bone marrow? a. lymphocyte b. megakaryocyte c. eosinophil d. reticulocyte

B

which type of leukocyte increases during allergic reactions and parasitic worm infections? a. basophil b. eosinophil c. lymphocyte d. neutrophil

B

oxygen attaches to a(an) _____ ion in the hemoglobin a. calcium b. sodium c. iron d. potassium

C

the extrinsic pathway of coagulation is initiated by a. platelets b. fibrinogen c. factor VIII d. damage of tissue

D

which of the following is not a function of blood? a. prevention of fluid loss b. transport of nutrients and waste c. maintenance of constant pH levels d. production of hormones

D

What are the structural and molecular differences between type A-blood and type B- blood?

a person with type A blood will have A antigens on the surface of his cells and anti-B antibodies in the blood plasma.

what sequence of events in the common pathway?

activated factor X combines with factors II and V Ca, and platelet factor 3 to form prothromvin activator. prothrombin activator then converts prothrombin to thrombin, which in turn converts soluble fibrinogen into insoluble fibrin. Factor XIII cross-links and stabilizes the fibrin monomerws into a fibrins polymer that serves as the "framework" of a clot.

What is the most abundant type of plasma protein, and what are its functions?

albumins are the most abundant of the blood proteins. they serve as transport vehicles for lipid-soluble molecules, and contribute to the oncotic gradient.

what are alpha- and beta-globulins? what do they do?

alpha and beta globulins are integral structural components of hemoglobin. they form a heterotetramer molecule bound to four heme groups. the four iron ions within heme groups bind oxygen to form oxyhemoglobin. the globulin molecules can also bind carbon dioxide, forming carbaminohemoglobin.

how do the functions of the basophils differ from those of the lymphocytes?

basophils are involved in the release of histamine and heparin during anti-inflammatory or allergic reactions. lymphocytes attack pathogens, destroy cancer cells, coordinate immune cell activity, and produce antibodies.

What are the main dissolved substances found in plasma?

blood contains numerous dissolved substances including electrolytes, nutrients, gases, and waste products.

how does blood help regulate body temperature?

blood plasma absorbs and distributes heat throughout the body. blood vessels in the dermis can dilate and dissipate heat.

How does blood help regulate temperature and fluid levels in the body?

blood plasma absorbs and distributes heat throughout the body. blood vessels in the dermis can dilate and dissipate heat. blood is capable of exchanging water with interstital fluid and of picking up additional fluids and water from alimentary canal. this is possible because of plasma proteins in the blood producing an oncotic gradient, regulating the movement of fluids into or out of the blood

What are some of the materials that blood transports?

blood transports dissolved molecules, ions, and formed elements such as erythrocytes, leukocytes, and platelets throughout the body.

what occurs during a vascular spasm, and how long does this phase last?

during a vascular spasm a blood vessel constricts suddenly and, in so doing, limits the amount of blood that can leak from the damaged vessel. the vascular spasm phase usually lasts for several minutes.

What is the main function of an erythrocyte, and in what ways is an erythrocyte designed to efficiently carry out its function?

erythrocytes are optimized for the transport of oxygen and carbon dioxide. they lack nuclei or organelles but contain over 280 million hemoglobin molecules in their cytoplasm. they also have biconcave shape which allows them to stack into columns rouleau as they pass through narrow vessels. spectrin proteins in the plasma membrane allow them to flex as they enter narrow capillaries.

what is the shape of an erythrocyte and why is this shape advantageous to its function?

erythrocytes have an unique bioconcave disk structure that allows respiratory gases to be loaded and unloaded rapidly and efficiently. additionally their structure facilitates both a single-line stacking of these cells, termed a rouleau, as they pass through small blood vessels and some flexibility of the cells to permit their passage through the smallest vessels.

what is fibrinolysis, and what is its purpose?

fibrinolysis is the degradation of fibrin by plasmin resulting in the destruction of fibrin framework of a clot

what is hemopoiesis? what is a hemocytoblast? briefly describe the two lines of blood cells that develop during hemopoiesis.

formed elements int he blood are formed by hemopoiesis. hemocytoblasts are the hemopoietic stem cells from which formed elements are derived. there are two lines of blood cell development; the myleoid line that gives rise to erythrocytes, megakaryocytes, and all leukocytes except lymphocytes and the lymphoid line that forms lymphocytes.

How does hematocrit vary among individuals?

hematocrit values carry somewhat and are dependent upon the and and sex of the individual. adult males tend to have a hematocrit ranging between 42% and 56%, whereas adult females' hematocrits range from 38% to 46%

What are the precursor cells ultimately from leukocytes?

hemocytoblasts give rise to myeloid and lymphoid stem cells. myeloid stem cells differentiate into granulocytes and monocytes lymphoid stem cells give rise to lymphocytes.

where does hemopoiesis occur in (a) the fetus, (b) a child, and (c) and adult?

hemopoiesis occurs in most bones in young children but as an individual reaches adulthood, hemopoiesis is restricted to selected bones in the axial skeleton. fetal hemopoiesis begins in the liver and then migrates to bone marrow.

Will blood be able to properly carry out its functions of blood pH is significantly altered? Why or why not?

if the pH of blood is altered from the normal range, plasma proteins become denatured and are unable to carry out their functions.

What are the roles of the different colony-stimulating factors (CSF-s) in hemopoiesis?

multi-colony-stimulating factor increases the formation of erythrocytes, as well as all classes of granulocytes, monocytes, and platelets. granulocyte-macrophage colony-stimulating factor accelerates the formation of granulocytes and monocytes. granulocyte colony-stimulating factor stimulates the formation of granulocytes. macrophage colony-stimulating factor stimulates the production of monocytes. thrombopoietin stimulates the production of megakaryocytes in the bone marrow and the subsequent formation of platelets. erythropoietin increases the rate of production and maturation of erythrocyte progenitor and erythroblast cells.

What type of leukocyte may increase in number if you develop "strep throat" (an infection of the throat by Streptococcus bacteria)?

neutrophilia, and increased number of neutrophils, results in response of acute infections such as strep throat.

what are the anatomic characteristics of each type of leukocyte? how can you tell these leukocytes apart when you view a blood smear under the microscope?

neutrophils have a multilobed (as many as five lobes) and cytoplasm with pink-orange to reddish granules. eosinophils have a bilobed nucleus and cytoplasm with pink-orange to reddish granules. basophils have a bilobed or S-shaped nucleus and cytoplasm with deep-purple granules. lymphocytes have a round or slightly indented nucleus that fills the cell. the nucleus is darkly stained and surrounded by a thin rim of cytoplasm. these four leukocytes are about one and a half times the diameter of an erythrocytes. monocytes have a kidney or U-shaped pale-staining nucleus with abundant cytoplasm. they are almost three times the diameter of a erythrocyte.

how are respiratory gases (oxygen and carbon dioxide) transported by erythrocytes?

oxygen is transported through the blood as oxyhemoglobulin bound to the iron-containing heme groups of hemoglobin. caron dioxide can be transported in one of three ways; dissolved in blood plasma as carbonic acid, as carbon dioxide dissolved in plasma or bound directly to hemoglobin as carbaminohemoglobin.

How are plasma protein levels related to colloid osmotic pressure?

plasma proteins exert osmotic pressure and prevent the loss of fluid from the blood as it moves through the capillaries. this osmotic force is responsible for drawing fluids into the blood and preventing excess fluid loss between blood capillaries and the intersitial fluid, thus maintaining blood volume and pressure

briefly describe the origin, structure, and functions of platelets?

platelets are continually produced in the red bone marrow by cells called megakaryocytes. megakaryocytes extend long processes through the blood vessel wall. these proplatelets are sliced by the force of the blood flow against the platelets. they help produce clots to prevent blood loss.

what is the function of platelets, and what is their life span?

platelets serve an important function in hemostasis (blood clotting). they circulate in the blood for 8 to 10 days

What prevents platelets from forming plugs in healthy blood vessels? What substances assist platelets with forming plugs in damaged blood vessels?

prostacyclins on the surface endothelial cells initiate pathways that prevent platelets form forming plugs in undamaged vessels. in damaged tissues platelets adhere to exposed collagen fibers with the help of vonWillebrand factor.

at what point in blood loss in the sympathetic nervous system typically activated, and what physiologic changes occur?

the autonomic nervous system is activated once 10% of the blood volume is lost from blood vessels, causing vasoconstriction, increased heart rate, and overall increased cardiac output

when blood is centrifuged, a thin whitish-grey layer called the buffy coat covers the packed erythrocytes. what are the components of the buffy coat?

the buffy coat contains leukocytes and platelets.

in what ways do the intrinsic and extrinsic pathways of the clotting cascade differ?

the intrinsic pathway is initiated by damage to the inside of the vessel wall and is initiated by platelets. this pathway typically takes approximately 3 to 6 minutes. in contrast the extrinsic pathway is initiated by damage to the tissue that is outside of the vessel, and this pathway usually takes approximately 15 seconds

A person undergoes a routine blood test and is found to have a leukocyte count of 7000 cells per cubic millimeter and 60% of the cells are neutrophils. is this individual healthy? Explain

the person is healthy in terms of the white blood cell differential count. the normal range for leukocytes in the blood is 4500 to 11000 circulating cells per microliter, where 50% - 70% of the cells are neutrophils

What are the three components visible in a centrifuged blood sample?

the three layers of centrifuged blood are erythrocytes, plasma and the buffy coat

describe the three phases of hemostasis and list the major events that occur in each phase.

the three phases of hemostasis are vascular spasm, platelet plug formation, and coagulation. the vascular spasm involves constriction of the damaged blood vessel, limiting blood loss. platelet plug formation begins with adhesion of platelets to exposed collagen fibers at the side of the damage, forming the initial plug. the subsequent coagulation phase is characterized by the production of an insoluble fibrin mesh, formed from plasma fibrinogen and numerous formed elements within the blood.

How to transferrin, ferritin, and hemosiderin participate in recycling erythrocyte components?

transferrin and ferritin participate in recycling the iron ion of hemoblobin. transferrin removes and transports the ion to the liver, where it is passed to ferritin which stores it until it is needed and transported to the red bone marrow.

what are some ways that red bone marrow changes in the elderly?

with age, red bone marrow is replaced by fat.