CH 23 Flashcards
Vessels and circulation; Veins and arteries
1
Q
Systemic circulation
A
Consists of all blood vessels that extend to all body regions
2
Q
Pulmonary circulation
A
Consists of blood vessels that take blood to and from the lungs for the purpose of gas exchange
3
Q
Companion vessels
A
When an artery travels with a corresponding vein because they supply the same body region and tend to lie next to each other
4
Q
Tunic
A
Layers of vein and artery wall
5
Q
Tunics surround the ______
A
lumen: inside space of the vessel where blood flows
6
Q
Tunics of blood vessels
A
- Tunica intima
- Tunica media
- Tunica externa
7
Q
Tunica intima aka tunica interna
A
Innermost layer of blood vessel
8
Q
Components of tunica intima
A
- Endothelium
- Subendothelial layer
- Internal elastic lamina*
- not in veins
9
Q
Endothelium
A
Simple squamous ET that lines the blood vessel lumen
10
Q
Subendothelial
A
Made of thin layer of areolar loose CT
11
Q
Internal elastic lamina
A
Elastic CT typically only in arteries; separates the tunica intima and tunica media
12
Q
Tunica media
A
Middle layer of vessel walls
13
Q
Components of tunica media
A
- Smooth muscle
- External elastic lamina*
- not in veins
14
Q
Vasoconstriction
A
Sympathetic innervation causes smooth muscle to contract
All arteries are capable of this, amount of vasoconstriction is regulated by proportion of smooth muscle to elastic fibers. More smooth muscle = greater vasoconstriction
15
Q
Vasodilation
A
Sympathetic innervation causes smooth muscle cells to relax, dilate, or widen
16
Q
External elastic lamina
A
Elastic CT, only in arteries
17
Q
Tunica externa
A
Outermost layer of vessels that helps anchor the vessel to other vessels; separates the tunica media and tunica externa
18
Q
Components of tunica externa
A
- Areolar CT that contains elastic and collagen fibers
- Vasa vasorum
19
Q
Vasa vasorum
A
- Means “vessels of vessels”
- Network of small arteries in very large vessels to supply blood to tunica externa
20
Q
Thickest wall layer in arteries
A
Tunica media
21
Q
Thickest wall layer in veins
A
Tunica externa
22
Q
Arteries become progressively (smaller/larger) as they branch and extend farther from the heart, as the veins become progressively (smaller/larger) as they unite and merge and come closer to the heart
A
smaller; larger
23
Q
Veins vs. arteries
A
Arteries tend to have more collagen and elastic fibers in all their tunics, which means that artery walls tend to remain open/ patent, can spring back into shape, and can withstand changes in blood pressure
Vein walls tend to collapse if there is no blood in the vein
24
Q
Capillaries only contain the _______
A
tunica intima
contains basement membrane and endothelium only
Lacks CT and muscle layers, allowing for rapid gas and nutrients exchange between blood and tissues
25
Arterioles
Smallest arteries
Have less than 6 layers of smooth muscle in tunica
Large arterioles have all 3 tunics, small arterioles have an endothelium surrounded by a single layer of smooth muscle cells
26
Veins
Drain capillaries into heart
27
Venules
Smallest veins that are companion vessels with arterioles; merge to form veins
28
Smallest venules
Postcapillary
29
Diapedesis
Mechanism by which leukocytes migrate from blood to interstitial fluid; occurs mainly in postcapillary venules
30
Capillary bed
Group of 10 to 100 capillaries (capillaries don't operate independently)
31
Capillary beds are fed by ___________
metarterioles
32
Metarteriole
Cross between an arteriole and capillary (contains smooth muscle); vessel branch of arteriole
33
Thoroughfare channel
Distal part of metarteriole that contains no smooth muscle; continuous with all vessels
34
Thoroughfare channels carries blood (towards/away from) ________(vessel) and leads to __________
away from capillaries; venules
35
Postcapillary venule
Connects to a thoroughfare channel; drains capillary bed
36
True capillaries
Branch from metarteriole that makes up the bulk of a capillary bed; capillary that directly branches off metarteriole
37
Precapillary sphincter
Smooth muscle ring that controls blood flow into true capillaries; entrance to capillary
Relaxation of precapillary sphincter allows blood flow into true capillaries
Contraction reroutes blood from metarteriole to thoroughfare channel to postcapillary venule
38
Elastic arteries AKA conducting arteries
Largest arteries that conduct blood away from heart to smaller muscular arteries; Abundance of elastic fibers allow elastic artery to stretch when a heart ventricle ejects blood into vessels
39
Muscular arteries AKA distributing arteries
Medium-sized arteries that distribute blood to the body, organs, and tissue; elastic fibers are confined to 2 circumscribed rigns
40
Functional unit of cardiovascular system
Capillaries
41
What do capillaries connect?
Arterioles to venules
42
Types of capillaries
- Continuous
- Fenestrated
- Sinusoid
43
Systemic circulation steps
1) Oxygenated blood flows from the LA to the LV then is pumped into the aorta
2) Blood passes from aorta into elastic arteries to muscular arteries to arterioles
3) Blood in arterioles enters systemic capillaries for exchange of gases and nutrients
4) Deoxygenated blood exits capillary beds into venules and veins
5) Deoxygenated blood is conducted to either SVC or IVC and then enters RA
LA
LV
aorta
elastic arteries
muscular arteries
arterioles
systemic capillaries
capillary bed
venules and veins
SVC or IVC
RA
44
Pulmonary circulation steps
6) Blood flows from the RA to RV then is pumped to the pulmonary trunk
7) Pulmonary trunks conducts deoxygenated blood into pulmonary arteries to the lungs
8) Blood passes through smaller and smaller arteries before entering pulmonary capillaries for gas exchange
9) Oxygenated blood exits the lung via series of progressively larger veins that merge to form the pulmonary veins
10) Pulmonary veins drain in the LA
11) Cycle repeats
RA
RV
pulmonary trunk
pulmonary arteries
pulmonary veins
LA
45
Pulmonary circulation is responsible for carrying (deoxygenated/oxygenated) blood from the (left/right) of the heart to the lungs and returning newly oxygenated blood to the (left/right) side of the heart
deoxygenated; right; left
46
Arteries carry deoxygenated blood, veins carry oxygenated blood
Pulmonary circulation
47
Systemic circulation is responsible for carrying (deoxygenated/oxygenated) blood from the (left/right) side of the heart and returning (deoxygenated/oxygenated) blood back to the right side of the heart
oxygenated; left; oxygenated
Left side of heart is oxygenated
48
Arteries carry oxygenated blood, veins carry deoxygenated blood
Systemic circulation
49
Arteries and veins of the heart
Arteries:
- R/L coronary arteries
- Marginal artery
- Circumflex artery
- Anterior interventricular artery
- Posterior interventricular artery
Veins:
- Anterior cardiac vein
- Small cardiac vein
- Middle cardiac vein
- Great cardiac vein
- Coronary sinus
50
Coronary arteries
- Supplies wall of heart
- Travels in coronary sinus
- R/L
51
Only branch of ascending aorta
Coronary arteries
52
Oxygenated blood is pumped out of the LV of the heart and enters the _______
ascending aorta
53
The ascending aorta curves toward the left side of the heart and becomes the ________
aortic arch
54
Coronary sulcus AKA atrioventricular sulcus
Deep groove separating the atria and ventricles that extends the entire heart circumference
55
Branching of right coronary artery
- Right marginal artery
- Posterior interventricular artery
56
Right marginal artery
Branches of right coronary artery; supplies right ventricle
57
Posterior interventricular artery
Supplies posterior surface of heart of both left and right ventricles
58
Branching of left coronary artery
- Anterior interventricular artery
- Circumflex artery
59
Anterior interventricular artery
Branching of left coronary artery that supplies anterior surface of left and right ventricles and most of the interventricular septum
60
Circumflex artery
Supplies left atrium and ventricle
61
Anatomoses
Tiny connections of arteries; where 2 arteries or 2 veins converge to supply the same body part
62
Functional end arteries
Artery with tiny anatomoses that it can be considered an end artery
e.g. coronary artery
63
End artery
Artery with no anatomoses; providing only one pathway to which blood can reach an organ
e.g. renal and splenic artery
64
Venous return
Flood of blood from systemic circulation towards the right of the heart (flow of blood back to heart); occurs in cardiac veins
65
Great cardiac vein
Runs alongside anterior interventricular artery
66
Middle cardiac vein
Runs alongside posterior interventricular artery
67
Small cardiac vein
Travels close to the right marginal artery
68
Anterior cardiac veins
Drains small portion of anterior surface of ventricle into RA
69
Coronary veins
Carries blood away from tissue it travels through
70
Coronary sinus
Large vein in posterior aspect of coronary sulcus; Drains directly into RA of heart; Carries blood away from heart wall
71
Pulmonary circuit
- Pulmonary trunk
- R/L pulmonary arteries
- Pulmonary veins
72
Pulmonary trunk
Large artery that transports blood from RV into pulmonary circulation
73
Pulmonary artery
Branchings of pulmonary trunk that carry deoxygenated blood to lungs
74
Pulmonary veins
Where oxygenated blood travels to the LA
75
Aorta
Artery that conducts blood from LV to systemic circulation
76
3 branches of aorta off the aortic arch
- Brachiocephalic trunk
- Left common carotid artery
- Left subclavian artery
77
Bifurnicate
Branches off
78
Brachiocephalic trunk bifurnicates into
- Right common carotid artery
- Right subclavian artery
79
Right common carotid artery
Supplies arterial blood to the right side of head and neck
80
Right subclavian artery
Supplies right upper limb and some thoracic structures
81
Left common carotid artery
Supplies left side of head and neck
82
Left subclavian artery
Supplies left upper limb and some thoracic structures
83
Descending thoracic aorta
Continuation of aortic arch curve that projects inferiorly and extends and branches to supply thoracic walls
84
Descending abdominal aorta
Inferior extension of descending thoracic aorta through the aortic opening in the diaphragm; Arterial branches originate from arterial wall to supply abdominal wall and organs
85
Hiatus
Aortic opening
86
Common iliac arteries
- R/L
- Branching of descending abdominal aorta at L4
87
Branching of common iliac arteries
- Internal iliac artery
- External iliac artery
88
Internal iliac artery
Supplies pelvic and perineal regions
89
External iliac artery
Supplies lower limbs; main arterial supply of lower limbs
90
Branches off aorta (both thoracic and abdominal)
- Visceral branch
- Parietal branch
91
Visceral branch
Supplies organs and associated tissues
92
Parietal branches
Supplies wall (or floor) of cavity
93
Visceral branches of thoracic aorta
- Bronchial
- Esophageal
- Pericardial
- Mediastinal
94
Bronchial artery
Supplies lungs
95
Esophageal artery
Supplies esophagus
96
Pericardial artery
Supplies pericardium
97
Mediastinal artery
Supplies posterior mediastinum
98
Parietal branches of thoracic aorta
- Posterior intercostal
- Superior phrenic
99
Posterior intercostal artery
Supplies wall of thoracic cavity (ribs, intercostal muscles)
100
Superior phrenic artery
Supplies diaphragm
101
Visceral branches of abdominal aorta
- Celiac trunk
- Superior mesenteric
- Inferior mesenteric
- Renal
- Suprarenal
- Gonadal
102
Arteries supplying the GI tract
- Celiac trunk
- Superior mesenteric
- Inferior mesenteric
103
Celiac trunk
- Inferior to hiatus (aortic opening)
- Supplies stomach, liver, spleen, part of duodenum, part of pancreas
104
Branches of celiac trunk
- Common hepatic
- Splenic
- Left gastric
105
Left gastric artery
Supplies lesser curvature of stomach
106
Splenic artery
Supplies spleen
107
Common hepatic artery
Supplies liver
108
Superior mesenteric artery
- Inferior to celiac trunk
- Supplies small intestine and half of large intestine
109
Inferior mesenteric artery
Supplies half of large intestine
110
Renal artery
Supplies kidneys
111
Middle suprarenal/adrenal artery
Supplies adrenal glands
112
Gonadal artery
Supplies gonads (testicles in male, ovaries in females)
113
Parietal branches of the abdominal aorta
Supply wall of abdomen
- Lumbar
- Inferior phrenic
- Median sacral
114
Lumbar artery
Supplies posterior abdominal wall
115
Inferior phrenic artery
Supplies diaphragm
116
Median sacral artery
Supplies the coccyx, sacrum, surrounding
117
Branching of common carotid arteries
- External carotid artery
- Internal carotid artery
118
External carotid artery
Supplies structures external to the skull (superficial tissue of face and bone)
119
Internal carotid artery
Supplies structures internal to skull
120
Vertebral arteries
Arise from subclavian arteries and travel through transverse foramina of cervical vertebrae to drain some cranial blood; supplies spinal cord, medulla
121
Anterior and middle cerebral arteries
Continuation of internal carotid artery through carotid canal to the inside of the skull; Supply the cerebrum of brain
122
Cerebral arterial circle/ Circle of Willis
Anatomosis of arteries around sella turcica; equalizes blood pressure in the brains
- Anterior communicating artery
- Anterior cerebral artery
- Internal carotid
- Posterior communicating artery
- Posterior cerebral artery
123
Basilar artery
Merging of vertebral arteries; travels anterior to pons; Supplies pons and cerebellum
124
Anterior communicating artery
Connects the 2 anterior cerebral arteries
125
Posterior communicating artery
Branches of posterior cerebral arteries
126
Branches off subclavian artery
- Vertebral
- Anterior intercostal
127
Anterior intercostal artery
Branch off internal thoracic aorta and forms of anatomoses with posterior intercostal arteries
128
Axillary artery
Extension of subclavian artery past the 1st rib border
129
Brachial artery
Extension of axillary artery past the inferior border of the teres major
130
Branches of brachial artery
- Radial artery
- Ulnar artery
Both supply the forearm and wrist
131
Superficial palmar arch
Formed primarily by ulnar artery
132
Deep palmar arch
Formed primarily by radial artery
133
Digital arteries
Branch from palmar arches to supply the fingers
134
Most common site for pulse
Radial artery
135
Femoral artery
Extension of external iliac artery past the inguinal ligament; Deep femoral artery supplies hip joint and most of thigh muscles
136
Popliteal artery
Extension of femoral artery past the knee; supplies the knee joint and muscles
137
Branching of the popliteal artery
- Anterior tibial artery
- Posterior tibial artery
138
Anterior tibial artery
Supplies the anterior compartment of the leg
139
Posterior tibial artery
Supplies the posterior compartment of the leg
140
Fibular artery
Extension of the posterior tibial artery; supplies the lateral compartment of the legs
141
Medial and lateral plantar arteries
Extension of the posterior tibial artery that branches at the plantar surface of the foot (top of foot)
142
Dorsal pedis artery
Extension of anterior tibial artery past the ankle
143
Plantar arch
Formed by the dorsal pedis and lateral plantar arteries
144
Digital arteries
Extend from the plantar arch and supply the toes
145
Brachiocephalic veins
Veins that drain the head, neck, and upper limbs
L/R
146
Superior vena cava
Merged brachiocephalic veins; drains directly into RA
147
Inferior vena cava
Merged large veins inferior to diaphragm; drains directly into RA; responsible for transporting venous blood from lower limbs, pelvis, perineum, abdominal structures
148
Which veins drain into the azygous system of veins along the posterior thoracic wall?
Lumbar and posterior intercostal veins
149
Azygous vein
Drains right side veins of thoracic and abdominal veins
150
Which veins does the azygous vein receive blood from?
- Hemiazygous
- Esophageal
- Bronchial
- Pericardial
151
The azygous vein drains into the __________
Superior vena cava
hemiazygous and accessory azygous
azygous
SVC
RA
152
Which veins drain the left side veins of thoracic and abdominal veins?
Hemiazygous and accessory azygous veins
153
Azygous and hemiazygous vein
Drain chest wall and lungs
154
Dural venous sinus
Large veins between the two layers of dura mater that primarily drain cranial blood and receive excess CSF
Do not have valves, blood can flow in multiple directions
155
Dural venous sinus system
- Superior sagittal sinus
- Inferior sagittal sinus
- Straight sinus
- Transverse/lateral sinus
- Sigmoid sinus
156
Superior sagittal sinus
- Superior to longitudinal fissure of brain
- Drains into one of transverse sinuses (usually right one)
157
Inferior sagittal sinus
Found in free inferior edge of falx cerebri
158
Straight sinus
- Formed by union (merging) of the inferior sagittal sinus and great cerebral vein
- Drains into transverse sinus
159
Transverse/ lateral sinus
Receives blood from straight sinus; travel horizontally along internal margin of occipital bone
L/R
160
Sigmoid sinus
- S-shaped sinus L/R sinuses that are continuation of transverse sinuses
- Drain into internal jugular veins
161
Internal jugular vein
- Receives blood from sigmoid sinus
- Merges with subclavian vein to form brachiocephalic vein that drains into SVC of heart
162
External jugular vein
- Site of venous return of facial veins
- Drains into subclavian then brachiocephalic vein
163
Basilic vein
- Runs adjacent to medial surface of upper limbs
- Eventually forms the axillary vein (deep)
- Superficial
164
Cephalic vein
- Runs lateral of upper limb
- Drains into the axillary vein
- Superficial
165
Median cubital vein
- Obliquely positioned in cubital region
- Common site for venipuncture to puncture a vein and draw out blood or inject a solute (IV)
- Superficial
166
Venous arches
- Palmar (deep and superficial) and dorsal (in hand)
- Plantar and dorsal (in foot)
167
Venae commitantes
Paired veins that lie alongside an artery
e.g. radial and ulnar veins (deep)
168
Vertebral vein
Drains tissue of neck
Brain
Internal jugular
External jugular
Vertebral
169
Dorsal venous arch of foot drains into which veins?
Great and small saphenous vein (superficial)
170
Great saphenous vein
- Medial surface of lower limb
- Drains into femoral vein
- Longest vein in body
171
Small saphenous vein
- Lateral ankle to posterior calf
- Drains into popliteal vein
172
Hepatic portal system
- Venous network that drains the GI tract and shunts blood for absorption and processing of transported materials
- Carries blood from organs of digestion to liver
- Blood circulates through hepatic sinusoids in liver and pathogens are phagocytized
- Blood returns to heart via hepatic veins and IVC
- Portal: detour before heart
173
Veins of hepatic portal system
- Superior mesenteric vein
- Inferior mesenteric vein
- Gastric veins
- Splenic vein
- Hepatic portal vein
- Hepatic veins
174
Superior mesenteric vein
Drains entire small intestine, half of large
175
Inferior mesenteric vein
Drains half of large intestine
176
Splenic vein
Drains spleen and pancreas
177
Gastric veins
Drains blood from stomach
178
(Hepatic) portal vein
Carries deoxygenated but nutrient-rich blood to liver
179
What veins form the hepatic portal vein?
- Inferior mesenteric vein
- Splenic vein
- Superior mesenteric
180
Hepatic vein
Carries blood away from liver and drains into IVC
181
Hepatic portal system steps
1) Inferior mesenteric v
2) Superior mesenteric v
3) Splenic v
4) Gastric vv
1-4 form hepatic portal vein
5) liver (hepatic sinusoid)
6) hepatic vein
7) IVC
182
Fetal circulation
- Placenta
- Umbilical cord
- Ductus venosus
- Foramen ovale
- Ductus arteriosus
183
Why is the fetal circulation system different than postnatal?
Fetal lungs are not functional, so BP in pulmonary arteries and right side of heart is greater than left side of heart
Fetal vessels help shunt blood directly to organs in need, away from organs that are not yet functional
184
Placenta
Temporary organ that delivers oxygen and nutrients from mother directly to fetus
185
Umbilical cord
- Umbilical vein (1)
- Umbilical arteries (pair)
186
Umbilical vein
Origin of umbilical system of veins are a left and right, by 2nd month, right disappears and left directly connects to ductus venosus; delivers oxygenated blood from placenta to fetus
187
Umbilical arteries
Returns deoxygenated blood to placenta
188
Ductus venosus
Connects umbilical vein to IVC
189
The ductus venosus becomes the _________ postnatally
ligamentum venosum
190
Umbilical arteries becomes the ________ postnatally
medical umbilical ligaments
191
The umbilical vein becomes the _______ postnatally
round ligament of liver (ligamentum teres)
192
Ductus arteriosus
Connects pulmonary trunk to aorta; vessel detour
193
The ductus arteriosus becomes the ___________ postnatally
Ligamentum arteriosum
194
Foramen ovale
Connection between R & L atriums; opening in interatrial septum
195
Steps of fetal circulation
1) Oxygenated blood from the placenta enters the body of the fetus through the umbilical vein
2) Blood from umbilical vein is shunted away from the liver and directly toward the IVC through the ductus venosus
3) Oxygenated blood in ductus venosus mixes with deoxygenated blood in IVC
4) Blood from the SVC and IVC empties into the RA
5) Since pressure is greater on the right side, most blood is shunted from RA to LA through the foramen ovale
6) Blood flows through LV and is pumped out of the aorta
7) A small amount of blood enters the right ventricle and pulmonary trunk, much is shunted from pulmonary trunk to aorta through ductus arteriosus
8) Blood travels to rest of body, deoxygenated blood returns to placenta through pair of umblical arteries
9) Nutrient and gas exchange occur in placenta, cycle repeats
Placenta
Umbilical vein
Ductus venosus
IVC
SVC + IVC -> RA
Foramen ovale
LA
LV
Aorta
Some enters RV and pulmonary trunk
Pulmonary trunk --> ductus arteriosus --> aorta
Umbilical arteries
Placenta
