Cardiovascular system: Vessels and Circulation Flashcards
Vessels and Circulation (156 cards)
1
Q
DEFINE ARTERIES
A
TAKE BLOOD FROM HEART TO CAPILLARIES
2
Q
DEFINE CAPILLARIES
A
MICROSCOPIC VESSELS, SUBSTANCES READILY EXCHANGE ACROSS THEM
3
Q
DEFINE VEINS
A
TAKE BLOOD FROM CAPILLARIES TO THE HEART
4
Q
WHAT IS THE LUMEN? AND WHAT SURROUNDS THEM?
A
INSIDE SPACE OF THE VESSEL THROUGH WHICH BLOOD FLOWS; TUNICS SURROUND THEM
5
Q
WHAT ARE THE THREE LAYERS FOUND IN THE WALLS OF VESSELS?
A
TUNICA INTIMA- INNERMOST
TUNICA MEDIA- MIDDLE
TUNICA EXTERNA-OUTERMOST
6
Q
WHAT TYPE OF TISSUE IS THE THREE VESSEL WALLS ARE MADE OF ?
A
TUNICA INTIMA: SIMPLE SQUAMOUS EPITHELIUM AND AREOLAR CONNECTIVE TISSUE
TUNICA MEDIA: CIRCULAR LAYERS OF SMOOTH MUSCLE WITH ELASTIC FIBERS
TUNICA EXTERNA: AREOLAR CONNECTIVE TISSUE
7
Q
WHAT TWO VESSEL WALLS HAVE SPECIAL CHARACTERISTICS AND WHAT ARE THEY?
A
TUNICA MEDIA-
CONTRACTION->VASOCONTRICTION
RELAXATION->VASODILATION
TUNICA EXTERNA- ANCHORS THE VESSELS TO OTHER STRUCTURES , VASA VASORUM
8
Q
WHAT DOES IT MEAN THAT MOST VESSELS ARE COMPANION VESSELS?
A
THEY LIE NEXT TO EACHOTER; WILL HAVE A ARTERY AND A VEIN FOR THE SAME BODY REGION
9
Q
THICKER THAN TUNICA MEDIA
THINNER LUMEN
MORE ELASTIC AND COLLAGEN FIBERS
A
ARTERIES
10
Q
THICKER TUNICA EXTERNA
LARGER LUMEN
LESS ELASTIC AND COLLAGEN FIBERS
A
VEINS
11
Q
CONTAIN ONLY TUNICA INTIMA
THIN WALL ALOW RAPID GAS AND NUTRIENT EXCHANGE
A
CAPILLARIES
12
Q
AS _____ BRANCH AND GET FURTHER FROM THE HEART, HOW DO THEY CHANGE?
A
ARTERIES; DECREASE LUMEN DIAMETER, DECREASE ELASTIC FIBERS, INCREASE AMOUNT OF SMOOTH MUSCLE
13
Q
WHAT ARE THE THREE TYPES OF ARTERIES FROM LARGEST TO SMALLEST?
A
ELASTIC, MUSCULAR, ARTERIOLES
14
Q
LARGE, HAVE ALOT OF ELASTIC FIBERS, STRETCH AND RECOIL, CAN PROPEL BLOOD DURING DIASTOLE
A
ELASTIC ARTERIES
15
Q
WHAT IS THE FUNCTION OF ELASTIC ARTERIES? PROVIDE 2 EXAMPLES
A
BRING BLOOD FROM THE HEART TO MUSCULAR ARTERIES
EXAMPLE: PULMONARY TRUNK, AORTA
16
Q
MEDIUM, MUSCLE IN WALLS CAN VASOCONTRICT OR VASODILATE, BRANCH INTO ARTERIOLES
A
MUSCULAR ARTERIES
17
Q
WHAT IS THE FUNCTION OF MUSCULAR ARTERIES? PROVIDE 2 EXAMPLES
A
TAKE FROM ELASTIC ARTERIES AND BRING IT TO SPECIFIC BODY REGIONS
EXAMPLES; CORONARY, INFERIOR MESENTERIC ARTERIES
18
Q
T/F MUSCULAR ARTERIES HAVE TWO LAYERS OF ELASTIC TISSUE
A
TRUE
19
Q
WHAT ARE THE TWO LAYERS OF ELASTIC TISSUE IN MUSCULAR ARTERIES AND WHERE ARE THEY LOCATED?
A
INTERNAL ELASTIC LAMINA: BETWEEN TUNICA INTIMA AND TUNICA MEDIA
EXTERNAL ELASTIC LAMINA: BETWEEN TUNICA MEDIA AND TUNICA EXTERNA
20
Q
SMALLEST, THE LARGER ONES WILL HAVE THE THEREE TUNICS, THE SMALLER ONES ARE ONLY ONE LAYER OF SMOOTH MUSCLE WITH A THIN ENDOTHELIUM, SMOOTH MUSCLE IS CONTRICTED
A
ARTERIOLES
21
Q
WHAT IS THE FUNCTION OF ARTERIOLES?
A
THEY CONTROL YOUR BLOOD PRESSURE AND BLOOD FLOW THROUGHOUT YOUR BODY, USING THIER MUSCLES TO CHANGE THIER DIAMETER
22
Q
ATHEROSCLEROSIS
A
PROGRESSIVE DISEASE IN ELASTIC AND MUSCULAR ARTERIES. PLAQUE IS PRESENT AND THICKENS THE TUNICA INTIMA; NARROWS ARTERIAL LUMEN
23
Q
WHAT ARE SOME CAUSES OF ATHEROSCLEROSIS?
A
INFECTION, TRAUMA, HYPERTENSION, HIGH CHOLESTEROL
24
Q
WHAT IS AN ANEURYSM?
A
PART OF THE WALL OF THE ARTERIOLE THINS AND BALLOONS; MAKES WALL MORE PRONE TO RUPTURE AND BLEEDING LEADING TO DEATH
25
CHARACTERISTICS OF CAPILLARIES
SMALL, ERYTHROCYTES TRAVEL THROUGH THEM IN SINGLE FILE, CONNECT ARTERIOLES TO VENULES
26
What is the functional advantage of the structure of the walls of capillaries?
endothelial layer on a basement membrane, allows for better exchange
27
what are continuous capillaries and where do you find them?
most common type of capillary, endothelial cells are in a continuous lining around the lumen
locations: muscle, skin, thymus, lungs, brain, spinal cord
28
TRUE OR FALSE: LARGE PARTICLES CANNOT GET THROUGH CONTINUOUS CAPILLARIES
TRUE
29
WHAT ARE FENESTRATED CAPILLARIES AND WHERE DO YOU FIND THEM?
ENDOTHELIAL CELLS ARE CONTINUOUS BUT HAVE PORES IN THEM.
LOCATION: INTESTINES, KIDNEYS
30
TRUE OR FALSE: SMALLER PLASMA PROTEINS CAN GET THROUGH FENESTRATED CAPILLARIES
TRUE
31
WHAT ARE SINUSOIDS AND WHERE DO YOU FIND THEM?
ENDOTHELIAL CELLS ARE FORMING AN INCOMPLETE LINING LEAVING LARGE GAPS
LOCATION: BONE MARROW, SPLEEN, SOME ENDOCRINE GLANDS
32
TRUE/FALSE: LARGE SUBSTANCES CAN GET THROUGH SINUSOIDS LIKE FORMED ELEMENTS AND LARGE PROTEINS (BLOOD CELLS, PROTEIN)
TRUE
33
WHAT ARE CAPILLARY BEDS?
A GROUP OF CAPILLARIES THAT WORKS TOGETHER
34
WHAT DETERMINES IF BLOOD CAN ENTER A CAPILLARY BED?
SPHINCTERS
35
WHAT IS THE DIFFRENCES BETWEEN WHEN CAPILLARY BEDS ARE RELAXED AND CONTRACTED?
RELAXTION--> BLOOD CAN ENTER
CONTRACTION--> BLOOD DOES NOT ENTER, CONTINUES MOVING PAST
36
VENULES
SMALLEST VEINS, THEY COME BACK TOGETHER, OTHER SIDE OF CAPILLARIES
37
WHAT ARE THE VENULES COMPANION VESSELS?, WHAT DO THEY MERGE TO FORM?
ARTERIOLES; VEINS
38
VEINS
SMALL, MEDIUM SIZED AND LARGE, MOST HAVE MANY VALVES
39
WHAT ARE THE COMPANION VESSELS FOR SMALL, MEDIUM AND LARGE VEINS?
SMALL/MEDIUM: MUSCULAR ARTERY
LARGE: ELASTIC ARTERY
40
WHAT IS TE FUNCTION OF THE VALVES FOUND IN MOST VEINS?
PREVENT BLOOD FROM POOLING IN LIMBS
ENSURE BLOOD FLOWS TO THE HEART
MADE OF TUNICA INTIMA + ELASTIC AND COLLAGEN FIBERS
** ONLY IN VEINS NOT ARTERIES**
41
WHAT ARE SYSTEMIC VEINS?
BLOOD RESERVOIRS: AT REST THEY CONTAIN 55% OF BLOOD VOLUME
42
HOW DOES BLOOD MOVE OUT OF SYSTEMIC VEINS OR POOL BACK INTO SYSTEMIC VEINS?
WHEN VEINS CONTRICT, BLOOD MOVES INTO CIRCULATION WHEN BODY IS ACTIVE
WHEN VEINS DILATE, BLOOD POOLS BACK IN SYSTEMIC VEINS WHEN BODY IS RESTING
43
DESCRIBE SIMPLE PATHWAYS
ONE MAJOR ARTERY BRINGS BLOOD TO ANB ORGAN OR REGION: BRANCHES INTO ARTERIES AND THEN ARTERIOLES: ARTERIOLES FEED INTO CAPILLARY BED, VENULE DRAINS CAPILLARY BED, VENULES MERGE INTO MAJOR VEIN
44
EXAMPLES OF SIMPLE PATHWAYS
SPLENIC ARTERY->SPLEEN-->SPLENIC VEIN
45
WHAT IS AN ARTERIAL ANASTOMOSIS
TWO MORE MORE ARTERIES CONVERGE TO SUPPLY SAME REGION
46
WHAT IS VENOUS ANASTOMOSIS
MORE COMMON, TWO MORE MORE VEINS DRAIN THE SAME REGION
47
ARTERIOVENOUS
TRANSPORTS BLOOD DIRECTLY FROM ARTERY TO VEIN
48
DESCRIBE PORTAL SYSTEM AND THE FLOW THROUGH THE ASSOCIATED STRUTURES. PROVIDE EXAMPLE
TWO CAPILLARY BEDS IN SEQUENCE ;
ARTERY-->CAPILLARY BED--> PORTAL VEIN--> CAPILLARY BED--> VEIN
EXAMPLE: HYPOTHALAMO- HYPOPHYSEAL PORTAL SYSTEM
49
HOW DOES CROSS SECTIONAL AREA CONTRIBUTE TO BLOOD VESSEL VELOCITY?
AS THE TOTAL CROSS SECTIONAL AREA OF THE VESSELS INCREASES, THE VELOCITY OF FLOW DECREASES.
50
WHERE WILL BLOOD MOVE SLOWLY IN BLOOD FLOW VELOCITY AND WHY IS THIS BENEFICIAL?
BLOOD FLOW IS SLOWEST IN THE CAPILLARIES, ALLOWS TIME FOR EXCHANGE OF GASES AND NUTRIENTS
51
WHAT IS EXCHANGED IN CAPILLARY EXCHANGE? NAME THE THREE METHODS
CAPILLARIES EXCHANGE GAS, NUTRIENTS, WASTE, AND HORMONES BETWEEN BLOOD AND TISSUES
THREE METHODS: DIFFUSION, VESICULAR TRANSPORT, BULK FLOW
52
WHAT IS THE METHOD OF EXCHANGE FOR DIFFUSION?
SUBSTANCES ENTER OF LEAVE BLOOD BASED ON CONCENTRATION GRADIENT
- HIGH TO LOW.
53
DIFFUSION: WHAT CAN MOVE THIS WAY? HOW?
SMALL SOLUTES GO THROUGH ENDOTHELIAL CELLS OR INTERCELLULAR CLEFTS, LARGE SOLUTES USE FENESTRATIONS OR GAPS
54
VESICULAR TRANSPORT: WHAT CAN MOVE THIS WAY? HOW?
PINOCYTOSIS AND EXOCYTOSIS
ENDOTHELIAL CELLS FORM FLUID FILLED VESICLES AT THE PLASMA MEMBRANE, TRANSPORT ACROSS CELL, SECRETE AT THE OTHER SIDE OF CELL USING EXOCYTOSIS
EXAMPLE; FATTY ACIDS
55
**BULK FLOW: WHAT IS THE METHOD OF EXCHANGE?
FLUIDS MOVE DOWN A PRESSURE GRADIENT, MOVEMENT DEPENDS ON NET PRESSURE, HYDROSTATIC PRESSURE VERSUS COLLOID PRESSURE
56
**BULK FLOW: WHAT IS FILTRATION? WHERE DOES IT OCCUR?
MOVEMENT OF FLUID OUT OF BLOOD; OCCURS AT THE ARTERIAL END OF THE CAPILLARY
57
**BULK FLOW: WHAT CAN/CANNOT MOVE DURING FILTRATION ?
SMALL SOLUTES AND FLUID EASILY MOVE THROUGH CAPILLARY OPENINGS; LARGE SOLUTES CANNOT MOVE THROUGH
58
**BULK FLOW: WHAT IS REABSORPTION AND WHERE DOES IT OCCUR?
FLUID MOVES INTO BLOOD; OCCURS AT THE VENOUS END OF THE CAPILLARY
59
**WHAT DO YOU CALL FORCE EXERTED BY BLOOD?
HYDROSTATIC PRESSURE
60
**What is blood hydrostatic pressure? What does it promote?
forces exerted by blood on the vessel wall
promotes filtration from the capillary
61
**What is interstitial hydrostatic pressure?
force of the interstitial fluid outside the vessel
in most tissues that is close to
62
**what is colloid osmotic pressure?
the pull on water due to the present of proteins (proteins=colloid)
63
**What is blood colloid osmotic pressure? What does it promote?
draws fluid into the blood due to blood proteins
promotes reabsorption
64
**What is interstitial fluid colloid osmotic pressure?
draws fluid into interstitial fluid
65
How is net filtration pressure calcualted?
(hydrostatic pressure of blood- hydrostatic pressure of interstitial fluid)-(colloid osmotic pressure of blood-colloid osmotic pressure of interstitial fluid)
66
net filtration pressure: where is it higher/lower? what does each favor?
NFP is higher on the arterial end of the capillary
(favors filtration)
NFP is lower on the venous end of the capillary
(favors reabsorption)
67
what is the role of the lymphatic system?
-pumps things around the body, picks up excess fluids that was no reabsorbed at the venous end of the capillaries
-About 15% of the fluid that entered the capillary
- will get filtered and returned to venous circulation
68
local blood flow: how is it measured and what does it depend on?
measured in mL in a minute
depends on:
tissue vascularity
myogenic response
local regulatory factors
total blood flow
69
What is vascularization and what does it depend on?
extends of vessels within the tissue; tissues that are more metabolically active have high vascularity
70
What is angiogenesis? Provide examples of tissues that will do this.
forms new vessels to increase perfusion potential
examples:
skeletal muscles will do this when aerobic training occurs
adipose tissue does this with weight gain
coronary vessels do this when they are being blocked
71
What is regression? Provide examples of tissues that will do this.
when tissues return to previous state of blood vessels
examples:
skeletal muscle will do this after becoming sedentary
adipose tissue does this when weight is lost
72
what is myogenic response?
smooth muscle in the wall of the vessel keeps local flow relatively constant
73
Myogenic response: What happens if systemic blood pressure rises?
systemic blood pressure rises--> more blood into arteriole--> stretches it;
smooth muscle responds by contracting
local flow returns to normal levels
74
myogenic response: What happens if systemic blood pressure drops?
systemic blood pressure drops--> less blood in arteriole--> less stretch
smooth muscle responds by relaxing
local flow returns to normal levels
75
short term regulation: How do vasoactive chemicals affect local blood flow? Hint: vasodilators and vasoconstrictors
vasodilators dilate the arterioles and relax the sphincters
increases flow into capillary beds
vasoconstrictors constrict the arterioles and contract the sphincters
decreases flow into capillary beds
76
Short term regulation: How does autoregulation affect local blood flow? Hint: negative feedback
tissue can control own local blood flow
tissue activity increases, prefusion is inadequate, signals are cent to dilate vessels
as perfusion increases, vessels constrict
77
Short term regulation: How does reactive hyperemia affect local blood flow? provide example
blood flow increases after temporary disruption
ex: entering a warm room after being cold
78
Short term regulation: How does reactive inflammation affect local blood flow? provide example
damaged tissues, leukocytes, and platelets release vasoactive chemicals
ex: histamine and bradykinin cause arterioles to dilate
79
Short term regulation: How does tissue damage affect local blood flow? provide examples
can release vasoconstrictors to prevent blood loss through damaged vessels
ex: leukotrienes and thromboxanes
80
Total blood flow: what is it? when does it equal ?
amount of blood through vasculature per unit time; equals cardiac output
81
when does total blood flow increase?
increases within exercise; more blood becomes available to tissues
82
total blood flow: what does regulation depend on?
regulation depends on heart and the vessels
83
Blood pressure: what is it?
The force of blood against the wall of the vessel
84
Blood pressure: what is the blood pressure gradient and what does it cause?
change in pressure from one end of the vessel to the other
-propels blood through the vessels
-higher in arteries and lower in veins
85
ARTERIAL BLOOD PRESSURE: WHAT IS IT?
BLOOD FLOW THROUGH ARTERIES PULSES WITH CARDIAC CYCLE
86
What is the systolic pressure?
what does it correspond with?
What is it in a blood pressure reading?
- WHEN VENTRICLES CONTRACT
-HIGHEST PRESSURE IN THE ARTERIES
-UPPER NUMBER IN BLOOD PRESSURE RATIO
87
What is the diastolic pressure?
what does it correspond with?
What is it in a blood pressure reading?
-WHEN VENTRICLES RELAX
-LOWEST PRESSURE IN THE ARTERIES
-LOWEST NUMBER OF BLOOD PRESSURE RATIO
88
What is pulse pressure?
how is it measured?
What does it reflect?
- PRESSURE IN ARTERIES ADDED BY HEART CONTRACTION
- DIFFRENCE BETWEEN SYSTOLIC AND DIASTOLIC PRESSURE
-REFLECTS ELASTICITY AND RECOIL OF VESSEL
89
PULSE: WHAT VESSEL TYPE GIVES YOU A PULSE?
THROBBING ARTERIAL WALL
90
PULSE: WHAT CAN CHANGE THE PULSE?
THE LACK OF FLOW
91
PULSE: WHAT ARE PULSE POINTS?
WHEN YOU OMPRESS AN ARTERY AGAINST SOLID STRUCTURE ; WHEN YOU COMMONLY TAKE A PULSE
92
MEAN ARTERIAL PRESSURE: WHAT IS IT?
-AVERAGE ARTERIAL BLOOD PRESSURE ACROSS THE ENTIRE CARDIAC CYCLE
-WEIGHTED MORE TO DIASTOLIC PRESSURE BECAUSE DIASTOLE LASTS LONGER THAN SYSTOLE
93
MEAN ARTERIAL PRESSURE: HOW IS IT CALCULATED?
MAP= DIASTOLIC PRESSURE + 1/3 PULSE PRESSURE
94
MEAN ARTERIAL PRESSURE: WHAT INFORMATION DOES IT GIVE?
-PROVIDES INDEX OF PERFUSION
IF ITS BELOW 60 THAT CAN MEAN INSUFFICIENT BLOOD FLOW
95
DEFINE CAPILLARY BLOOD PRESSURE
HOW IS IT DIFFRENT FROM ARTERIAL?
FLOW AND PRESSURE ARE SMOOTH
NO FLUCTUATION BETWEEN SYSTOLIC AND DIASTOLIC
96
CAPILLARY BLOOD PRESSURE: WHY IS IT IMPORTANT TO BE WITHIN A CERTAIN RANGE?
if it is to high it could damage the fragile capillaries
97
DEFINE VENOUS BOOD PRESSURE; WHAT DOES IT DEPEND ON
VENOUS RETURN OF BLOOD TO THE HEART; DEPENDS ON PRESSURE GRADIENT, SKELETAL MUSCLE PUMP, AND RESPIRATORY PUMP
98
VENOUS BLOOD PRESSURE: HOW IS IT DIFFRENT FROM ARTERIAL BLOOD PRESSURE?
LOW, NOT PULSATILE, SMALL PRESSURE GRADIENT
99
SKELETAL MUSCLE PUMP: HOW DOES THIS HELP VENOUS PUMP?
-VEINS SQUEEZES AS MUSCLE CONTRACTS
-BLOOD GETS PUSHED, VALVES PREVENT BACKFLOW
- MOVES MORE QUICKLY WHEN EXERCISING
100
SKELETAL MUSCLE PUMP: WHAT HAPPENS WITHOUT IT?
PROLONGED INACTIVITY WILL CAUSE BLOOD TO POOL IN LEGS
101
RESPIRATORY PUMP: HOW DOES THIS HELP WITH VENOUS RETURN?
HELPS VENOUS RETURN IN THE THORAX
102
RESPIRATORY PUMP: INSPIRATION VS. EXPIRATION
INSPIRATION: ABDOMINAL PRESSURE INCREASES AND THORACIC PRESSURE DECREASES;BLOOD IN ADBOMINAL VEINS--> THORACIC CAVITY
EXPIRATION: THORACIC PRESSURE INCREASES AS ABDOMINAL PRESSURE DECREASES ; BLOOD IN THORACIC--> HEART, BLOOD IN LOWER LIMBS--> ABDOMINAL VEINS
103
RESPIRATORY PUMP: WHAT HAPPENS IF YOU INCREASE BREATHING RATE?
IF INCREASE BREATHING RATE, BLOOD MOVES MORE
104
RESISTANCE: WHAT IS IT?
FRICTION THAT BLOOD ENCOUNTERS WHEN IT CONTACTS THE VESSEL WALL
105
RESISTANCE: WHAT DOES IT OPPOSE?
THE FLOW OF BLOOD; PERIHERAL RESISTANCE
106
RESISTANCE: DEFINE VISCOSITY?
RESISTANCE OF FLUID TO ITS FLOW
107
RESISTANCE: HOW CAN VISCOSITY INCREASE/DECREASE?
GREATER THICKNESS=GREATER VISCOSITY=MORE RESISTANCE
MORE PARTICLES IN THE FLUID= MORE THICKNESS
LESS PARTICLES IN THE FLUID= LESS THICKNESS
108
RESISTANCE: WHAT IS VESSEL LENGTH? HOW CAN YOU CHANGE IT?
LONGER VESSELS HAVE MORE RESISTANCE; CHANGES WITH WWEIGHT GAIN OR LOSS
109
RESISTANCE: DEFINE VESSEL RADIUS; HOW ARE SMALL DIFFRENT FROM BIG?
SMALLER RADIUS HAS MORE RESISTANCE
LARGE DIAMETER= LESS RESISTANCE=INCREASED FLOW
110
RELATION OF BLOOD FLOW TO RESISTANCE: HOW IS BLOOD CALCULATED?
BLOOD FLOW IS PROPORTIONAL TO THE PRESSURE GRADIENT DIVIDED BY RESISTANCE
111
RELATION OF BLOOD FLOW TO RESISTANCE: HOW DOES PRESSURE GRADIENT AFFECT BLOOD FLOW?
AS THE PRESSURE GRADIENT INCREASES, BLOOD FLOW INCREASES
CARDIAC OUTPUT CAUSES THE PRESSURE GRADIENT TO INCREASE
112
Keeping blood pressure in normal range: why is it important it falls within a range?
high enough to maintain perfusion
not high enough to damage vessels
113
keeping blood pressure in normal range: what does it depend on?
depends on certain variables:
cardiac output
resistance
blood volume
114
HOW ARE VARIABLES REGULATED KEEPING BLOOD PRESSURE IN NORMAL RANGE?
NERVOUS AND ENDOCRINE SYSTEM REGULATE THE VARIABLES
115
DESCRIBE HOW THE AUTONOMIC REFLEXES REGULATE BP ON A SHORT TERM BASIS? (NEURAL REGULATION)
NUCLEI IN THE MEDULLA OBLONGATA
QUICKLY ADJUST CARDIAC OUTPUT AND OR/RESISTANCE
116
WHEN IS NEURAL REGULATION USEFUL?
WHEN THEY HELP ADAPT TO MOMENTARY NEEDS LIKE STANDING UP
117
CARDIAC CENTER: WHAT DOES IT INFLUENCE?
CARDIAC OUTPUT
118
What are the two spots in the cardiac center and explain which pathways they use and what the effects are of each pathway.
CARDIOACCELERATORY CENTER: ORGIN OF SYMPATHETIC PATHWAY; INCREASES HEART RATE AND FORCE OF CONTRACTION;INCREASES CARDIAC OUTPUT AND BLOOD PRESSURE
CARDIOINHIBITORY CENTER: ORGIN OF PARASYMPATHETIC PATHWAYS; DECREASE HEART RATE AND SLOWS CONDUCTION OF ELECTRICAL SIGNALS; DECREASES CARDIAC OUTPUT AND BLOOD PRESSURE
119
VASOMOTOR CENTER: WHAT DOES IT INFLUENCE?
INFLUENCES VESSEL DIAMETER TO INFLUENCE RESISTANCE
120
VASOMOTOR CENTER: WHAT PATHWAY IS IT RELATED TO? HOW DOES IT WORK?
ORGIN OF SYMPATHETIC PATHWAYS
GO TO BLOOD VESSELS AND RELEASE NOREPINEPHRINE
CAUSES VESSEL CONSTRICTION IN MOST VESSELS
SOME VESSELS WILL DILATE
121
VASOMOTOR CENTER: WHAT DOES IT LEAD TO?
INCREASED PERIPHERAL RESISTANCE
-MORE VESSELS ARE CONTRICTED
LARGER CIRCULATING BLOOD VOLUME
-VOLUME IN VEINS SHIFTS BLOOD FROM RESERVOIRS TO CIRCULATION
REDISTRIBUTION OF BLOOD FLOW
-MORE BLOOD TO SKELETAL MUSCLES AND HEART
122
VASOMOTOR CENTER: HOW CAN YOU REVERSE IT?
IF INHIBIT SYMPATHETICS, REVERSE THESE CHANGES
123
BARORECEPTORS: WHAT ARE THEY?
NEVER ENDINGS THAT RESPOND TO STRETCH OF THE VESSEL WALL
124
Where are they located? Which nerve is used by each? And what is the affect of each?
LOCATED: AORTIC ARCH AND CAROTID SINUSES
AORTIC ARCH: VAGUS NERVE: CARDIOVASCULAR CENTER
- SYSTEMIC BLOOD PRESSURE REGULATION
CAROTID SINUS:GLOSSOPHARYNGEAL NERVE: CARDIOVASCULAR CENTER
-BLOOD PRESSURE OF THE HEAD AND NECK (VESSELS THAT GO TO THE BRAIN)
-MORE SENSITIVE
125
AUTONOMIC REFLEXES:What causes these reflexes to activate and what are they good for?
BARORECEPTOR REFLEX
INTITIATED BY CHANGE IN BLOOD PRESSURE
GOOD FOR QUICK CHANGE, NOT LONG TERM
126
AUTONOMIC REFLEXES: Explain what happens if blood pressure decreases.
-VESSEL STRETCH DECLINES,BARORECEPTOR FIRING DECREASES
-CARDIOACCELERATORY CENTER ACTIVIATED, STIMULATES SYMPATHETIC PATHWAYS TO INCREASE CARDIAC OUTPUT
-INHIBITS CARDIOINHIBITORY CENTER, MINIMIZES PARASYMPATHETIC ACTIVITY
-ACTIVATES VASOMOTOR CENTER, STIMULATE SYMPATHETIC PATHWAY TO INCREASE VASOCONSTRICTION
-INCREASES CARDIAC OUTPUT AND RESISTANCE, BLOOD PRESSURE RISES
127
AUTONOMIC REFLEXES: Explain what happens if blood pressure INCREASES.
-vessels stretch and baroreceptors firing both increase
-cardio acceleratory center sends less signals
-cardioinhibitory center activates parasympathetic pathways to the heart
-vasomotor center sends less signals
-decreases cardiac output and resistance, blood pressure drops
128
Chemoreceptor Reflexes:
Where are they located and what will trigger them?
located: peripheral chemoreceptors in aortic and carotid bodies
Triggered: negative feedback to return blood chemistry to normal
129
chemoreceptor reflexes: how do they work?
high carbon dioxide, low pH, or very low oxygen will stimulate chemoreceptors and vasomotor center
-increases BP and shifts blood to lungs
-carbon dioxide is expired and pH rises
130
Higher Brain Centers:
Describe the role of the hypothalamus in blood pressure.
can increase cardiac output and resistance
-can be due to increased body temp or fight or flight responses
131
Higher Brain Centers:
Describe the role of the limbic system in blood pressure.
can alter blood pressure in response to emotion or memories
132
Renin-Angiotensin System:
Where is angiotensinogen made?
liver makes inactive angiotensinogen, releases into blood
133
Renin-Angiotensin System:
what is released by the kidneys and when? Role?
-kidneys release renin when there is low blood pressure or sympathetic nervous system activity
-renin converts angiotensinogen to angiotensin 1
enzyme found in lung capillaries
134
Renin-Angiotensin System:
What is the role of angiotensin II in blood pressure regulation?
raises blood pressure
-powerful vasoconstrictor
-stimulates thirst center-fluid intake raises blood volume
-kidneys decrease urine formation- less fluid loss
-stimulates release of aldosterone and antidiuretic hormone
135
Aldosterone:
Where is it released from and what is its role in blood pressure regulation?
released: adrenal cortex
maintains blood volume and pressure
increases absorption of sodium ions and water in the kidney
-decreases urine output
136
Anti-diuretic Hormone:
What is it released from and what is its role in blood pressure regulation?
released: posterior pituitary
maintains or elevates blood pressure
137
Anti-diuretic Hormone: what are the effects?!
increases water reabsorption at the kidney-less fluid lost
stimulates thirst center: increases blood volume
can cause vasoconstriction: increase resistance and pressure
138
Atrial Natriuretic Peptide:
Where is it released from and when, and what is its role in blood pressure regulation?
released: by the atria when they are stretched by high blood volume
role: decreases blood pressure
139
Atrial Natriuretic Peptide: what are the effects?!
effects: vasodilation: increases peripheral resistance
increases urine output-lowers blood volume
140
what is hypertension?
chronically elevated blood pressure
systolic over 140mmHg
Diastolic over 90 mmHg
can damage blood vessel walls- atherosclerosis
can thicken arteriole walls- arteriolosclerosis
major cause of heart failure
141
What is hypotension?
chronically decreased blood pressure
systolic under 90mmHg
diastolic under 60mmHg
symptoms: dizziness, fatigue and fainting
142
What is orthostatic hypotension?
is when the drop in blood pressure is due to sudden standing
-regulation is not occurring quickly enough
143
Blood Flow During Exercise
Total Blood Flow
What changes occur while exercising?
heart beats faster and stronger
blood is removed from venous reservoirs
blood is redistributed so more goes to active tissues
144
Blood Flow During Exercise
Total Blood Flow
PROVIDE AT LEAST TWO EXAMPLES;
-flow to coronary vessels increases-heart wall gets more oxygen
-skeletal muscle blood flow increases
-flow to skin increase to dissipate heat
-less blood to abdomen and kidney
145
Describe the entire pathway of pulmonary circulation.
right ventricle(deoxygenated blood)--> pulmonary trunk
-splits into left and right pulmonary arteries
-go to left and right lungs
-arteries divide into smaller arteries and arterioles
arterioles branch into pulmonary capillaries
-gas exchange occurs at air sacs
-capillaries merge into venules and then pulmonary veins
-two left and two right pulmonary veins carry blood (oxygenated) to left atrium
146
How is pulmonary circulation different from systemic circulation?
less elastic
wider lumens
short because lungs are close to heart
lower blood pressure
147
Systemic Arteries: Where do they originate?
brain off the aorta
-oxygenated blood out of the left ventricle
left and right coronary arteries
-arise from ascending aorta
-supply heart wall
148
Systemic Arteries: what comes off the ascending aorta?
aortic arch
149
Systemic Arteries: What comes off the aortic arch? Describe any additional branches off of these vessels.
Brachiocephalic trunk
-becomes right common carotid
-supplies ride side of neck and head
becomes right subclavian arteries
-supplies right upper limb and some thoracic structures
left common carotid artery
-supplies left side of head and neck
left subclavian artery
-supplies left upper limb and some thoracic structures
150
Systemic Arteries: What comes off the descending aorta? Describe any additional branches off of these vessels.
-Branches off the descending thoracic aorta supplies thoracic wall and viscera
-splits at level L4
left and right common iliac arteries
each split into internal/external iliac
151
what does the descending aorta passes through?
-passes through diaphragm-->becomes descending abdominal aorta
152
what supplies the lower limb?
external iliac
153
What three vessels return blood flow to the right atrium?
SUPERIOR VENA CAVA
INFERIOR VENA CAVA
CORONARY SINUS
154
WHAT PARTS OF THE BODY SUPERIOR VENA CAVA IS BRINGING BLOOD FROM?
MERGER OF LEFT AND RIGHT BRACHIOCEPHALIC VEINS
PARTS: DRAINS HEAD, NECK, UPPER LIMBS, THORACIC AND ABDOMINAL WALLS
155
WHAT PARTS OF THE BODY INFERIOR VENA CAVA IS BRINGING BLOOD FROM?
FORMED FROM VEINS BELOW DIAPHRAGM
PARTS: LOWER LIMBS, PELVIS, PERINEUM AND ABDOMINAL STRUCTURES
156
WHAT PARTS OF THE BODY CORONARY SINUS IS BRINGING BLOOD FROM?
CARRIES DEOXYGENATED BLOOD FROM HEART
