Histology

Question 1

True or False: Cardiac muscle contains many nuclei

Answer 1

False; only 1 or 2

Question 2

True or False: Cardiac muscle nuclei are located centrally

Answer 2

True

Question 3

True or False: cardiac muscle is striated

Answer 3

True

Question 4

How many layers is the heart wall composed of and what are they

Answer 4

3 distinct layers: an outer epicardium, a middle myocardium and an inner endocardium

Question 5

Which cell type is in the epicardium

Answer 5

simple squamous epithelium

Question 6

True or false: cardiac muscle does not contain intercalated discs

Answer 6

False

Question 7

What type of junctions does the intercalated discs contain

Answer 7

Gap and adhering junctions

Question 8

Which of the two junctions in intercalated discs is responsible for electrical conduction

Answer 8

Gap junctions

Question 9

What is the role of purkinje cells in the heart

Answer 9

electrical impulse conduction

Question 10

A conducting system for initiation and propagation of rhythmic depolarizations is formed by which cell type of the heart

Answer 10

Purkinje fibers

Question 11

Which layer of serous pericardium lines the outer surface of the heart (visceral or parietal)

Answer 11

Visceral layer

Question 12

What type of cells line the percardial cavity

Answer 12

Mesothelial cells

Question 13

What are the three layers of heart valves

Answer 13

fibrosa, spongiosa and ventricularis

Question 14

The ventricularis layer of the heart valves continue into which structure in the AV valves

Answer 14

chordae tendineae

Question 15

What is the name of the cells in the SA and AV nodes that do not contain intercalated discs

Answer 15

nodal cardiac muscle cells

Question 16

What are the three layers of arteries and veins

Answer 16

tunica intima, tunica media and tunica adventitia

Question 17

What are the three components of the tunica intima layer

Answer 17

endothelium, subendothelial layer and internal elastic membrane

Question 18

What is the function of the external elastic membrane

Answer 18

separates the tunica media from the tunica adventitia

Question 19

Which layer of blood vessels consists of circumferentially arranged layers of cells

Answer 19

tunica media

Question 20

Which layer of blood vessels is composed of longitudinally arranged collagenous tissue and elastic fibers

Answer 20

tunica adventitia

Question 21

Tunica adventia is thicker in veins or arteries

Answer 21

veins

Question 22

Which layer of blood vessels contain a system of vessels called the vasa vasorum

Answer 22

tunica adventitia

Question 23

What is the function of the vasa vasorum

Answer 23

supplies blood to the vascular walls themselves

Question 24

Function of the nervi vasorum

Answer 24

control contraction of the smooth muscle in the vessel walls

Question 25

Which layer of blood vessels contain a system of vessels called the nervi vasorum

Answer 25

tunica adventitia

Question 26

What is the shape of the endothelial cells in blood vessels

Answer 26

flattened, elongated, and polygonally

Question 27

Example of three receptors found on the luminal surface of endothelial cells in blood vessels

Answer 27

low-density lipoprotein [LDL], insulin, and histamine receptors

Question 28

Which size arteries are elastic arteries

Answer 28

large arteries

Question 29

Which size arteries are muscular arteries

Answer 29

medium arteries

Question 30

Characteristics of large arteries

Answer 30

- multiple sheets of elastic lamellae in their walls. - tunica intima consists of endothelium, subendothelial connective tissue, and an inconspicuous internal elastic membrane - Endothelial cells participate in the structural and functional integrity of the vascular wall - tunica media consists of multiple layers of vascular smooth muscle cells separated by elastic lamellae - thin layer of tunica adventitia

Question 31

Characteristics of medium arteries

Answer 31

- more smooth muscle and less elastin in the tunica media - tunica intima is thinner and contains a prominent internal elastic membrane - tunica media is composed almost entirely of vascular smooth muscle - tunica adventitia is thick and separated from the tunica media by an external elastic membrane

Question 32

Characteristics of small arteries

Answer 32

- smooth muscle in the tunica media - tunica intima has an internal elastic membrane - gap junctions may be found between endothelial cells and the smooth muscle cells of the tunica media - tunica adventitia is a thin, ill-defined sheath of connective tissue that blends with the connective tissue

Question 33

Characteristics of capillaries

Answer 33

- smallest diameter blood vessels | - a single layer of endothelial cells and their basal lamina

Question 34

What are the different types of capillaries

Answer 34

continuous, fenestrated, and discontinuous (or sinusoidal)

Question 35

Characteristics of continuous capillaries

Answer 35

- ound in connective tissue; cardiac, skeletal, and smooth muscles; skin; lungs; and the CNS - uninterrupted vascular endothelium that rests on a continuous basal lamina

Question 36

Characteristics of fenestrated capillaries

Answer 36

- found in endocrine glands and sites of fluid or metabolite absorption, such as the gallbladder, kidney, pancreas, and intestinal tract - endothelial cells have numerous circular openings known as fenestrations - continuous basal lamina - a thin, nonmembranous diaphragm across its opening

Question 37

Characteristics of discontinuous capillaries

Answer 37

- found in the liver, spleen, and bone marrow - larger in diameter and more irregularly shaped than other capillaries - Vascular endothelial cells lining these capillaries have large openings in their cytoplasm and they are separated by wide, irregular, intercellular gaps - discontinuous basal lamina

Question 38

What are the types of veins

Answer 38

Venules, small, medium and large veins

Question 39

what is used to differentiate between a postcapillary venule and a muscular venule

Answer 39

muscular venules have a tunica media

Question 40

Which type of vein usually accompany arteries

Answer 40

medium veins

Question 41

which type of vein is continuous which muscular venules

Answer 41

small veins

Question 42

3 examples of large veins

Answer 42

superior and inferior vena cava and hepatic portal vein

Question 43

Characteristics of small veins

Answer 43

- diameters vary from 0.1 to 1 mm - All three tunics are present - Tunica media usually constitutes two or three layers of vascular smooth muscle - thicker tunica adventitia

Question 44

Characteristics of medium veins

Answer 44

- diameter of as much as 10 mm - valves - three tunics of the venous wall are most evident in medium-sized veins

Question 45

Characteristics of large veins

Answer 45

- tunica media is relatively thin - tunica adventitia is relatively thick - diameter greater than 10 mm

Question 46

Characteristics of lymph vessels

Answer 46

- more permeable than blood capillaries - collect excess protein-rich tissue fluid - lack a continuous basal lamina - Anchoring filaments extend between the incomplete basal lamina