Module 7 - Blood and Blood Vessels

Question 1

Formed elements

Answer 1

-erythrocytes, leukocytes, platelets
- arise from stem cells of the red bone marrow

Question 2

Plasma

Answer 2

-extracellular matrix that makes blood unique among connective tissues because it is fluid.
-yellow colored liquid
-Water, protein, nutrients

Question 3

Erythrocytes

Answer 3

-red blood cells, transport oxygen, and some carbon dioxide
-99% of blood cells
-Not true cells, no nucleus or organelles
-only one type
-short life span, but longer than leukocytes

Question 4

Blood type

Answer 4

classified according to the presence, or absence, of certain antigens; four major blood types are A, AB, B, and O

Question 5

Surface antigens (A & B)

Answer 5

the presence or absence of surface antigens A and B on red blood cells, known as the ABO blood group, is the primary factor that determines donor compatibility in blood transfusions

Question 6

Antibodies

Answer 6

A protein that acts against a specific antigen

Question 7

Rh Factor

Answer 7

Refers to the presence or absence of the Rh antigen on red blood cells.

Question 8

Leukocytes

Answer 8

-white blood cell
-protect the body against invading microorganisms and body cells with mutated DNA, and they clean up debris.
-larger than erythrocytes and are the only formed elements that are complete cells, possessing a nucleus and organelles
-many types
-short lifespan

Question 9

Granulocytes

Answer 9

-contain abundant granules within the cytoplasm. They include neutrophils, eosinophils, and basophils.

Question 10

Neutrophil

Answer 10

-most common; comprise 50–70 percent of the total leukocyte count
-rapid responders to the site of infection and are efficient phagocytes with a preference for bacteria

Question 11

Eosinophil

Answer 11

-represent 2–4 percent of the total leukocyte count
-Attack inflammation (include antihistamine molecules, which counteract the activities of histamines, inflammatory chemicals produced by basophils)
-Parasites (contain molecules toxic to parasitic worms)
Allergic reactions
-Phagocytic (the process by which cells surround and digest certain particles)
-High counts of eosinophils are typical of patients experiencing allergies, parasitic worm infestations, and some autoimmune diseases

Question 12

Basophil

Answer 12

-least common; typically comprising less than one percent of the total leukocyte count
-slightly smaller than neutrophils and eosinophils
-basophils intensify the inflammatory response
-granules of basophils release histamines, which contribute to inflammation, and heparin, which opposes blood clotting
-High counts of basophils are associated with allergies, parasitic infections, and hypothyroidism

Question 13

Agranulocytes

Answer 13

include monocytes, which mature into macrophages that are phagocytic, and lymphocytes, which arise from the lymphoid stem cell line.

Question 14

Lymphocytes

Answer 14

-only formed element of blood that arises from lymphoid stem cells
-the second most common type of leukocyte, accounting for about 20–30 percent of all leukocytes, and are essential for the immune response
-three major groups of lymphocytes include natural killer cells, B cells, and T cells

Question 15

Monocytes

Answer 15

-originate from myeloid stem cells
-normally represent 2–8 percent of the total leukocyte count
-able to migrate into tissues and transform into a macrophage.

Question 16

Hematopoiesis

Answer 16

-Production of blood cells
-Blood cells produced in the liver and spleen before birth
-Red bone marrow produces blood cells beginning ~ 5 months and is the primary site of hematopoiesis after birth
-Liver produces >90% of plasma proteins

Question 17

Anemia

Answer 17

When the number of red blood cells or hemoglobin is deficient; decreased hemacrit

Question 18

Platelets

Answer 18

-aka thrombocytes
-Smallest circulating formed elements – cell fragments
-Involved in clotting
-Lifespan of approximately 8 -10 days

Question 19

Vessel Wall Layers

Answer 19

tunica intima, tunica media, tunica externa

Question 20

Tunica intima

Answer 20

-the innermost layer of a blood vessel
-It is composed of a lining of endothelium and an underlying layer of connective tissue.

Question 21

Endothelium

Answer 21

Lining the tunica intima is the specialized simple squamous epithelium called the endothelium

Question 22

Tunica media

Answer 22

-layer is primarily composed of concentric layers of smooth muscle tissue
-The middle layer of a blood vessel
-The layer that is responsible for vasoconstriction and vasodilation.

Question 23

Tunica externa

Answer 23

-its fibers blend into the surrounding tissue, anchoring and stabilizing the blood vessel.
-The outermost layer of a blood vessel.

Question 24

Vasa vasorum

Answer 24

small blood vessels within the walls of larger arteries and veins; supply blood to outer part of the larger vessels

Question 25

Arteries

Answer 25

a blood vessel that carries blood away from the heart, where it branches into ever-smaller vessels

Question 26

Elastic arteries

Answer 26

closer to the heart; allow stretch as blood is pumped into them and recoil when ventricles relax

Question 27

Muscular arteries

Answer 27

distal to elastic arteries; deliver blood to body organs

Question 28

Distributing arteries

Answer 28

Carry blood to specific organs and tissues; also called muscular arteries

Question 29

Arterioles

Answer 29

vessels that are the smallest arteries

Question 30

Vasoconstriction

Answer 30

the constriction of blood vessels, which increases blood pressure.

Question 31

Vasodilation

Answer 31

widening of blood vessels

Question 32

Capillaries

Answer 32

tiny vessels that arterioles branch into where nutrients and wastes are exchanged, and then combine with other vessels that exit capillaries to form venules

Question 33

Continuous capillaries

Answer 33

-most common and found in almost all vascularized tissues -characterized by a complete endothelial lining with tight junctions between endothelial cells -complete basement membrane

Question 34

Fenestrated capillaries

Answer 34

-has pores (or fenestrations) in addition to tight junctions in the endothelial lining -These make the capillary permeable to larger molecules. -common in the small intestine, the primary site of nutrient absorption, and the kidneys, which filter the blood

Question 35

Sinusoids (sinusoidal) capillaries

Answer 35

-least common, flattened, and they have extensive intercellular gaps and incomplete basement membranes, in addition to intercellular clefts and fenestrations. -large openings allow for the passage of the largest molecules, including plasma proteins and even cells -blood flow very slow

Question 36

Capillary bed

Answer 36

-a network of capillaries in a tissue or organ -fed by an arteriole

Question 37

Metarteriole

Answer 37

-a type of vessel that has structural characteristics of both an arteriole and a capillary -Each metarteriole arises from a terminal arteriole and branches to supply blood to a capillary bed

Question 38

Thoroughfare channel

Answer 38

metarteriole that continues through capillary bed to venule

Question 39

Veins

Answer 39

Blood vessels that carry blood back to the heart; thin walls with large lumens. Generally appear flat

Question 40

Venules

Answer 40

small blood vessels that carry blood to a vein

Question 41

Valves

Answer 41

promote the unidirectional flow of blood toward the heart and prevent backflow toward the capillaries caused by the inherent low blood pressure in veins as well as the pull of gravity

Question 42

Collateral circulation

Answer 42

Alternative pathways for delivering blood to a region of the body; critical with blockage of a blood vessel

Question 43

Anastomosis

Answer 43

joining of two ducts, vessels, or bowel segments to allow flow from one to another

Question 44

Arteriovenous anastomoses

Answer 44

Regulate blood flow around capillary beds, connecting arteries directly with veins

Question 45

Arterio-arterial anastomoses

Answer 45

Provide collateral circulation to many organs and body regions

Question 46

Rh blood group

Answer 46

classified according to the presence or absence of a second erythrocyte antigen identified as Rh

Question 47

Polycythemia

Answer 47

A disorder characterized by an abnormal increase in the number of red blood cells in the blood

Question 48

What is hematocrit?

Answer 48

the ratio of the volume of red blood cells to the total volume of blood

Question 49

What is the buffy coat?

Answer 49

white blood cells and platelets

Question 50

What is the normal ratio of plasma, buffy coat, and hemacrit in blood?

Answer 50

55:1:44

Question 51

If you were looking at cross-sections of two blood vessels of relatively the same diameter, what features could you use to distinguish arteries from veins?

Answer 51

The artery wall is thicker with more smooth muscle, but the lumen is narrower.

Question 52

Lumen

Answer 52

-a hollow passageway through which blood flows -Arteries have smaller lumens than veins, a characteristic that helps to maintain the pressure of blood moving through the system

Question 53

Which of the following is true regarding red blood cells? 1. The hematocrit is a good approximation of red blood cells in the blood because red blood cells make up the majority of the formed elements. 2. The shape of red blood cells allows for greater surface area for diffusion of gasses. 3. Red blood cells play a critical role in controlling infections in the the body. 4. Red blood cells are spherical in shape. 5. Red blood cells transport oxygen and carbon dioxide in the bloodstream. 6. The shape of red blood cells causes them to be rigid and fragile, sometimes causing problems when they travel through capillaries.

Answer 53

1, 2, 5

Question 54

Muscular arteries:

Answer 54

have a thick media with a large amount of smooth muscle fiber within them

Question 55

Which of the following is true of an artery? 1. The adventitia is frequently absent. 2. The histological structure permits a two-way exchange of substances between the blood and body cells. 3. The vessel walls are relatively thin. 4. Blood flow is the slowest of all classes of vessels. 5. The lumen is relatively smaller than that of a corresponding vein.

Answer 55

5

Question 56

Which vessels collect blood from capillaries?

Answer 56

Venules

Question 57

In organs that function to filter the blood and remove contaminants, which of the following types of capillaries allow the greatest access to blood to perform this task? 1. fenestrated capillaries 2. continuous capillaries 3. arterioles 4. sinusoid capillaries

Answer 57

4. sinusoid capillaries

Question 58

What is the function of the valves within the veins?

Answer 58

to prevent the backflow of blood away from the heart

Question 59

Summarize the histological organization of blood vessels' walls?

Answer 59

The wall is composed of an outer layer of fibrous connective tissue, a middle layer with sheets of smooth muscle and an elastic framework, and a thin, smooth epithelial inner layer bound to areolar tissue.

Question 60

What is the correct comparison between the walls of arteries and veins? 1. Veins have thicker walls than arteries have 2. Veins have endothelial linings that appear pleated, but arteries do not. 3. Arteries have more smooth muscle and elastic fibers than veins have. 4. The media layer of veins is thicker because of increased layers of smooth muscle cells.

Answer 60

3. Arteries have more smooth muscle and elastic fibers than veins have.

Question 61

Which of the following is best adapted to dealing with pulses of high blood pressure?

Answer 61

elastic arteries

Question 62

Which type of white blood cell is most common?

Answer 62

neutrophils

Question 63

Which of the following statements are true? 1. A patient with type O- blood is known as the universal donor 2. A patient who is Rh+ can receive blood from a patient who is Rh+ or Rh- 3. A patient with type AB+ blood is known as the universal recipient 4. A patient with type A blood is compatible to receive a transfusion from type B 5. A patient with type AB blood is compatible to receive a transfusion from type A or B 6. A patient with type O blood is compatible to receive a transfusion from type AB 7. A patient with type B blood is compatible to receive a transfusion from type A

Answer 63

1, 2, 3, 5

Question 64

The primary site of hematopoiesis in an adult is:

Answer 64

the red bone marrow