Histology of Cardiovascular System Flashcards
(125 cards)
1
Q
What are the functional components of the cardiovascular system?
A
Blood vascular system and
Lymphatic vascular system
2
Q
Circulation from heart to lungs
A
Pulmonary circulation
3
Q
Circulation from heart to rest of the body
A
Systemic circulation
4
Q
What happens to the blood as it goes to smaller types of blood vessels?
A
It slows down
From 33 cm/s in the aorta and pulmonary artery to about 0.3 cm/s at the level of arterioles and capillaries
5
Q
The lymphatic vascular system merges with the _________ and eventually joins venous circulation.
A
Thoracic Duct
6
Q
What causes lymph movement?
A
Lymph movement is due to contraction of surrounding skeletal muscles, returning excess lymph to the blood circulatory system.
7
Q
The endothelium is has what kind of epithelial tissue type?
A
Simple squamous
8
Q
What are the vasoactive factors produced by the endothelium?
A
Nitric oxide - vasodilator
Endothelins - vasoconstrictor
9
Q
The endothelium converts ___________ to ____________ in order to increase blood pressure.
A
Angiotensin I to Angiotensin II
10
Q
What are the functions of the endothelium?
A
- Nutrient Exchange
- Vasoactive factor secretion
- Angiotensin conversion
- Lipolysis of lipoproteins
- Receptors for leukocyte binding
- Anti-thrombogenic functions
11
Q
Main component of tunica media
A
Smooth muscles
12
Q
True or false. Smooth muscles in the endothelium have their own basal lamina.
A
True
13
Q
Arrangement of smooth muscles in endothelium:
A
Circumferential
14
Q
Connective tissues have: __________ and __________
A
Collagen and elastic fibers
15
Q
Connective tissues are arranged:
A
Longitudinally
16
Q
3 layers of the blood vessels arranged from closest to lumen to periphery
A
Tunica intima
- endothelium
- basement membrane
- internal elastic lamina
Tunica media
- smooth muscle
- external elastic lamina
Tunica externa
17
Q
Epithelial type of tunica intima
A
Simple squamous endothelial cells
18
Q
The internal elastic lamina is a fenestrated sheet of collagen. True or false?
A
False, it’s a fenestrated sheet of elastin
19
Q
The internal elastic lamina is prominent in _________
A
Muscular arteries
20
Q
It consists of arranged smooth muscle cells arranged circumferentially around the lumen
A
Tunica media
21
Q
Increase in pressure leads to the ___________ of the tunica media
A
thickening
22
Q
Which has thicker tunica media? Heart or brain blood vessels?
A
Heart, because they experience greater pressure
23
Q
Tunica Externa/Adventitia is a _____________ composed of _______________, arranged ____________.
A
connective tissue composed of type I collagen and elastic fibers arranged longitudinally
24
Q
Microvasculature attached to the walls of thicker blood vessels to provide nutrients which cannot penetrate their thick walls:
A
Vasa vasorum
25
Location of vasa vasorum:
Tunica externa/advantitia and outer half of tunica media
26
Vasa vasorum supply these layer/s:
Tunica externa/adventitia and tunic media
27
Vasa vasorum more frequently seen in ________.
Veins (compared to arteries)
28
Histologically, how do you differentiate vasa vasorum from arterioles, venules, and capillaries?
Vasa vasorum are attached beside another bigger blood vessel
29
Nerves arising from the medullar oblongata, innervating blood vessels
Nervi vasorum
30
Nervi vasorum arise from ____________
Medulla oblungata (reticular center)
31
Nervi vasorum are found in bundles in the ___________.
Tunica adventitia
32
They are responsible for maintaining vasomotor tone
Nervi vasorum
33
Contraction of the ventricles forces blood into the arteries, making them expand. What do you call this?
Ventricular systole
34
Relaxation of the ventricles, blood continues to flow due to recoil from the elastic tissues of arteries. What do you call this?
Ventricular diastole
35
Three main types of arteries:
1. Elastic Arteries
2. Muscular Arteries
3. Arterioles
36
Largest type of artery:
Elastic arteries
37
Medium-sized artery:
Muscular arteries
38
Smallest type of artery:
Arterioles
39
This layer is broadest in arteries:
Tunica media
40
They are called conducting arteries and are considered as auxiliary pumps:
Elastic arteries
41
Responsible for ensuring the continuous flow of blood
Elastic arteries
42
Elastic fibers have a high amount of _______ in ________.
they have a high amount of elastin in tunica media
43
Examples of elastic arteries:
1. Aorta and its primary branches
- right brachiocephalic trunk
- left common carotid artery
- left subclavian artery
2. Pulmonary artery and its branches
44
Responsible for storage and secretion of von Willebrand factor, a glycoprotein responsible for platelet aggregation (clotting)
Weibel-Palade bodies
45
Weibel-Palade bodies are located in which layer?
Tunica intima
46
True or False. Only elastic arteries can store von Willebrand factor.
True
47
P-selectins are found in which layer?
Tunica intima
48
Fenestrated, concentrically-arranged sheets of elastin, interspersed between collagen fibers and smooth muscle cells
Tunica media
49
Elastin fibers appear black in _______ stain. Meanwhile, it appears pink in ________ stain.
Elastin fibers: Black in orcein stain while pink in H&E
50
Highly collagenous layer but may also have elastin
Tunica externa/adventitia
51
Nervi vasorum is located in which layer/s?
Tunica externa/adventitia
52
Vasa vasorum is located in which layer/s?
Tunica adventitia and tunica media
53
True or false. Elastic laminae are prominent in elastic arteries?
False, because they are continuous with the elastic fibers of the tunica media.
54
These are also known as distributing arteries
Muscular arteries
55
Type of artery responsible for the distribution of blood to the different parts of the body
Muscular arteries / Distributing arteries
56
Elastic arteries have much elastin in their tunica media. Meanwhile, muscular arteries have much _________ in their tunica media.
Smooth muscle
57
Examples of muscular arteries:
Brachial, Radial, Ulnar, Femoral, Popliteal arteries
| Cerebral and Coronary arteries
58
The tunica intima of muscular arteries have a more prominent ___________.
Internal elastic lamina
59
Contains fibroblasts, elastic, and collagen fibers arranged longitudinally.
Tunica adventitia
60
Bundles of unmyelinated axons terminate at this layer
External elastic membrane of tunica adventitia
61
Principal component of peripheral resistance to blood flow pressure:
Arterioles
62
Anti-hypertensive drugs act on which blood vessels?
Arterioles
63
Transition from large arteries to arterioles is evidenced by:
1. _______________
2. _______________
1. Reduction of internal elastic lamina
| 2. Reduction of smooth muscle in tunica media
64
These are transitional vessels from terminal arterioles to capillaries
Metarterioles
65
Metarterioles have a ________ layer of smooth muscles, spaced a short distance apart, completely encircle the tube of the epithelium.
Discontinuous
66
Smooth muscle cells continuous with the capillaries:
Precapillary sphincter
67
These are sensitive to the changes in chemical concentration of the blood (pH, CO2 and O2 levels)
Chemoreceptors like carotid body and aortic body
68
Chemoreceptors transmit signals to the _____________.
Respiratory system
69
Carotid body is located where?
Bifurcation of common carotid and internal carotid artery
70
Type of carotid body that secrete neurotransmitters:
Glomus (Type I)
71
Neurotransmitters secreted by glomus (type I):
Serotonin and Dopamine
72
Surrounds a cluster of 2-6 glomus cells:
Sheath (Type II)
73
Blood supply of carotid body:
Mayer's ligament
74
Innervation of carotid body:
CN IX (Hering's Nerve)
75
Chemoreceptor found between left common carotid and left subclavian:
Aortic body
76
Responsive to changes in blood pressure
Baroreceptors
77
Baroreceptor located at the wall of the internal carotid artery
Carotid sinus
78
Done to decrease blood pressure among hypertensive patients
Carotid massage
79
Innervation of carotid sinus
Hering's Nerve (CN IX)
80
Old people have higher blood pressure because ____________.
The elasticity of their blood vessels has significantly reduced
81
What tissue migrates into the tunica intima as one ages (leading to accumulation of fat)?
Smooth muscle from tunica media
82
Physiological response of blood vessels to aging
Arteriosclerosis
83
Accumulation of plaques secondary to the deposition of muscles in the tunica intima
Atherosclerosis
84
Occlusion in the coronary vessels
Myocardial infarction
85
Occlusion in a blood vessel in the brain
Cerebrovascular accident/ Stroke
86
Thinning and swelling of blood vessel wall
Aneurysm
87
Smallest diameter among blood vessels
Capillaries
88
Capillaries consists of:
a single layer of endothelial cells and their basal lamina
89
Capillaries don't have:
Tunica media and tunica adventitia
90
Special cells attached outside the endothelium that accompany capillaries
Pericytes
91
Pericyte process that is longitudinal
Primary process
92
Pericyte process that is circumferential
Secondary process
93
Function of pericytes
Capillary repair during injury
94
True or False. Pericytes have actin, myosin, and troponin.
True
95
Transport system of capillaries
Transcytosis
96
Vesicles derived from Golgi apparatus used by capillaries for transport
Caveolae
97
Type of capillaries found in internal organs (viscera) where high rate of nutrient exchange occurs
Fenestrated capillaries / Visceral capillaries
98
Continuous layer of endothelium around the lumen of the capillary without fenestrae
Continuous Capillaries / Somatic / Smooth capillaries
99
Type of capillary in muscles, connective tissues, nervous tissues, and lungs:
Continuous capillaries
100
Type of capillaries that have irregular outlines and varying shapes
Sinusoidal capillaries / Discontinuous capillaries
101
Capillaries found in the liver, spleen and bone marrow
Sinusoidal capillaries
102
Blood vessel with thin walls, lumen collapsed, and boundaries less distinct:
Veins
103
Smallest vein
Venule
104
Veins that branch immediately from the capillary and a site for exchange of nutrients and cell migration besides capillaries. They also serve as exit doors for WBCs (preferential site for migration of leukocytes).
Postcapillary venules
105
Extensions or semilunar folds of the intima that project into the lumen of the vein
Valves of veins
106
Vein with all three layer distinguishable:
Large veins - inferior vena cava, portal vein, splenic vein
107
Alternative microvascular pathway in which blood flows through two successive capillary beds separated by a portal vessel allowing effective delivery of nutrients.
Portal system
108
3 portal systems:
1. Hepatic portal system (Liver)
- hepatic portal vein
2. Renal portal system (Kidneys)
- efferent arteriole
3. Hypophyseal Portal System (Brain; Hypothalamus to Pituitary)
- hypophyseal portal vein
109
Portal system with the only atrial portal vessel
Renal portal system (efferent arteriole)
110
3 layers of cardiac wall
Endocardium, Myocardium, Epicardium
111
Epicardium type of epithelium:
Simple squamous endothelial cells with fibroelastic tissue
112
Continuous with the tunica adventitia of blood vessels
Epicardium
113
Thickest layer or the heart consisting mostly of cardiac muscle. It is continuous with the tunica media of blood vessels.
Myocardium
114
Continuous with the tunica intima of blood vessels. It is a single layer of squamous endothelial cells resting on a subendocardial layer.
Endocardium
115
3 layers of the endocardium and their contents
1. Inner layer: endothelium and connective tissue
2. Middle myoelastic layer: smooth muscle fibers and connective tissue
3. Deep layer/subendocardial layer: contains connective tissue, blood vessels, nerves, merges with the myocardium and contain Purkinje fibers
116
Pale-staining fibers due to high glycogen content with sparse peripheral myofibrils
Purkinje fibers
117
Pacemaker of the heart located near the junction of the superior vena cava and the right atrium
Sinoatrial Node
118
Located beneath the endocardium of the interatrial septum
Atrioventricular Node
119
Flow of polarization from the SA node
SA node -> AV node -> Bundle of His -> Bundle branches -> Purkinje fibers
120
Four fibrous rings surrounding the valve orifices
Annuli fibrosis
121
Atrial cardiac fibers attach to:
Annuli fibrosis of pulmonary artery and aorta
122
Ventricular cardiac fibers attach to:
Annuli fibrosis of atrioventricular valves
123
Structure that connects the rings of annuli fibrosis
Trigona Fibrosis (Fibrous trigone)
124
Single layer of endothelium with no fenestrations and no basal lamina
Lymphatic capillaries
125
Do lymphatic vessels have valves?
Yes, they come from the tunica intima
