Chapter 34 Part A: Circulatory System Flashcards
1
Q
What are the functions of the vertebrate circulatory system?
A
• Transportation – Respiratory role – Nutritive role – Excretory role • Regulation – Hormones of endocrine system – Temperature regulation • Protection – Blood clotting – Immune system
2
Q
What are the components of the vertebrate circulatory system?
A
• Blood & interstitial fluid • Blood vessels – Arteries, veins, & capillaries • Lymphatic system • Heart
3
Q
Blood & Interstitial Fluid
• Blood
A
– Composed of fluid plasma & “formed elements” (red & white blood cells, & cell fragments)
– Adult human has ~ 5.7 liters (1.5 gal) blood • ~ 55% is plasma
• ~ 45% is formed elements
4
Q
Adult human has ~ __ liters of blood
A
5.7 liters (1.5 gal)
5
Q
~1% of blood is plasma
~2% of blood is formed elements
A
- 55%
2. 45%
6
Q
Blood & Interstitial Fluid
• Plasma
A
– 90% water
– 7-8% soluble proteins
• Albumins: (60% of sol. proteins) main contributor to osmotic pressure, transport molecule, & pH buffer
• Globulins: (36%) large, diverse family, includes immunoglobulins, transport globulins (lipoprotein)
• Fibrinogen: (4%) source of fibrin in blood clots
– 1% electrolyes: mostly sodium, chloride, bicarbonate
– 1-2% materials in transit: nutrients, metabolic intermediates, dissolved gasses, hormones
– Plasma minus the fibrinogen is serum
7
Q
Plasma is: _1_% water _2_% soluble proteins _3_% electrolytes _4_% materials in transit
A
- 90%
- 7-8%
- 1%
- 1-2%
8
Q
_____ is the main contributor to osmotic pressure
A
Albumins
9
Q
Plasma minus fibrinogen is _____
A
Serum
10
Q
Blood & Interstitial Fluid
• Formed elements
– Red blood cells, or erythrocytes
A
• Contain hemoglobin, function in O2 transport, but also 20% of CO2
• In mammals, RBC’s lose nucleus and protein synthesizing machinery
– take on “biconcave shape” (30% more surface area than sphere)
– Live about 120 days
• Fraction of blood volume that is rbc’s is called the
hematocrit, ~45% in humans
• ~7-8μm in human, ~5,000,000 per mm3
• formed in red bone marrow, primarily of axial skeleton & girdles, proximal ends of femur & humerus; ~100 billion per day
11
Q
Erythrocytes contain _______ that functions in 02 transport, but also 20% of C02
A
Hemoglobin
12
Q
In ______, RBC’s lose nucleus and protein synthesizing
A
Mammals
13
Q
“Biconcave shape” of RBC’s increase surface area by __%
A
30%
14
Q
RBC’s live about ___ days
A
120 days
15
Q
Fraction of blood volume that is RBC’s is called the ______, ~45% in humans
A
Hematocrit
16
Q
RBC’s are ~__2__ small in humans
~__2__ per mm3
A
- 7-8μm
2. 5,000,000
17
Q
How many RBC’s are formed per day in red bone marrow?
A
~100 billion per day
18
Q
Blood & Interstitial Fluid
• Formed elements
– White blood cells, or leucocytes
A
• Nucleated, larger than rbc’s (~10-14μm)
• Commonly amoeboid, not confined to blood vessels like rbc’s
• 5 distinct types, names derived from staining properties (e.g., neutrophils, eosinophils, basophils, lymphocytes, monocytes, etc.)
– Life spans vary with type: a few hours to years, most are a few days
• Defense against invading microorganisms and foreign bodies
– Including role in immune system
• ~5,000 per mm3 , so ~1/1000 frequency of rbc’s
• Also formed in red bone marrow, but some complete differentiation in lymphoid tissue
19
Q
WBC’s are nucleated and __1__ in diameter, making them __2__ than RBC’s
A
- ~10-14μm
2. Larger
20
Q
WBC’s life span vary with type, ranging from __1__ to __2__, though most are __3__
A
- A few hours
- Years
- A few days
21
Q
WBC’s primary function is…
A
Defense against invading microorganisms and foreign bodies, including role in immune system
22
Q
WBC’s frequency is ~____ per mm3
A
~5,000 per mm3, so ~1/1000 frequency of RBC’s
23
Q
WBC’s are formed in red bone marrow, but some complete differentiation in ______ tissue
A
Lymphoid
24
Q
Blood & Interstitial Fluid
• Formed elements
– Platelets (cell fragments)
A
• In mammals, membrane-bound cell fragments, anucleate
• Accumulate at site of broken blood vessel and form a plug
• Plug (clot) is reinforced by network of fibers of the protein fibrin, from fibrinogen of plasma
– Complex cascading series of steps
• Platelets “bud off” special bone marrow cells (called megakaryocytes), very large (~60 μm diameter)
• Platelets ~ 2-4 μm diameter, 250,000 – 400,000 per mm3
• Life span: 5 – 10 days
25
True or False: In mammals, platelets are anucleate
True
26
True or False: Platelets accumulate at site of broken blood vessel and form a plug (clot)
True
27
Platelets are ~____ in diameter
2-4 μm
28
Platelets frequency is ____-____ per mm3
250,000-400,000 per mm3
29
Platelets life is __-__ days
5-10 days
30
Blood & Interstitial Fluid
| • Interstitial fluid
– The fluid that bathes the cells of the body
– “Forced out” of blood plasma by blood pressure in the capillaries
• Similar in composition to plasma but lacks large molecules
– ~ 12 liters in humans (c.f. ~5.7 liters of blood)
31
There is ~__ liters of interstitial fluid in humans
~12 liters (compared to ~5.7 liters of blood)
32
Blood Vessels
* Arteries
* Capillaries
* Veins
* Entire network forms ~60,000 miles in adult human
33
Entire network of blood vessels is ~______ miles in adult human
~60,000 miles
34
Blood Vessels
| • Arteries
– Carry blood away from the heart [this is how arteries are defined, not on basis of oxygen levels]
– Branch into smaller tubes
– Smallest branches called arterioles
– Arterioles feed smallest blood vessels, the capillaries
35
Arteries carry blood _____ the heart
Away from
36
Smallest branches of arteries are called _____
Arterioles, which feed into capillaries
37
Blood Vessels
| • Capillaries
– Smallest & most numerous blood vessels
| – Site of material exchange
38
The site of material exchange is in the _____
Capillaries
39
Blood Vessels
| • Veins
– Return blood from tissues to heart
– Smallest such vessels, on “downstream” side of capillaries, are called venules
– Larger return vessels are called veins
40
Veins carry blood _____ the heart
Back to, return blood from tissues to heart
41
Smallest branches of veins are called _____
Venules
42
Blood Vessels
| • Structure of arteries and veins
– Basic similarity
– From lumen of vessel outward (basically):
• Epithelium (endothelium), simple squamous
• Elastic fibers (more in arteries)
• Circular smooth muscle (arteries have thicker layer)
• Connective tissue
43
True or False: There are more elastic fibers in veins
False, more in arteries.
44
True or False: Arteries have a thicker layer of circular smooth muscle
True
45
Blood Vessels
| • Capillaries
– Only endothelium so very thin walls
– ~8 μm diameter (entire “tube” of a capillary), ~1 mm long
• 125 : 1, Length to Diameter
• So RBC’s (7-8 μm) must go through single file
– Although narrow, very abundant
• Total cross-sectional area exceeds that of arteries or veins
• So pressure and velocity are low
– Blood pressure “forces” some of fluid portion of blood out of capillary (through or between endothelial cells)
• RBC’s and larger molecules remain
• White blood cells are amoeboid and may exit
• Lipid soluble substances may exit
– Resulting osmotic gradient (soluble plasma proteins) returns some of fluid to capillaries exiting capillary bed
46
Capillaries are only made of ______ so they have very thin walls
Endothelium
47
Capillaries are ~_1_ in diameter
| Entire "tube" of a capillary is ~_2_ in length
1. ~8 μm diameter
2. 1 mm long
125 : 1, Length to Diameter
48
True or False: The total cross-sectional area of arteries or veins exceeds that of capillaries
False, Total cross-sectional area of capillaries exceeds that of arteries or veins
49
True or False: RBC's are 7-8 μm so they must go through capillaries, which are ~8 μm, single file.
True
50
The pressure and velocity are ___ in capillaries
Low
51
Blood Vessels
| • Venus return
– Blood pressure is low when blood exits capillaries so how does blood get back to heart?
• This low pressure is main force of venous return
• Veins have one-way valves that block flow back towards capillary bed
– Varicose veins are veins swollen by poor return due to faulty valves and lifestyle
• Veins tend to lie within major muscles, the contraction of which squeezes blood along veins
• Low pressure in veins created by relaxation of heart during normal contraction rhythm (diastole)
• Low pressure in chest cavity during inhalation also helps
52
True or False: The main force of venous return is the high blood pressure.
False, low pressure is the main force
53
______ veins are veins swollen by poor return due to faulty valves and lifestyle
Varicose
54
True or False: Arteries usually lie within major muscles, the contraction of which squeezes blood along
False, Veins usually lie within major muscles, the contraction of which squeezes blood along veins
55
Lymphatic system
• One-way system for draining tissues of excess interstitial fluid not recovered by venous end of capillary network; fluid called lymph
– ~3 liters per day in humans (so 3 L of 12 L total)
• Consists of:
• Lymphatic capillaries (slightly larger than blood
capillaries)
• Lymphatic vessels
• Lymph nodes
• Lymphatic organs (including spleen & thymus)
• Flow driven as for veins (one-way valves)
• In mammals, empties into venous system near the heart
• As lymph passes through lymph nodes (in series) it is “filtered” & exposed to lymphocytes (part of body’s defences)
56
True or False: The lymphatic system is a one-way system for draining tissues of excess interstitial fluid not recovered by venous end of capillary network; fluid called lymph
True
57
The lymphatic system drains ~__ liters of interstitial fluid per day in humans
~3 liters per day (so 3 L of 12 L total)
58
As lymph passes through lymph nodes (in series) it is "filtered" & exposed to ___1___ (part of body's defenses)
Lymphocytes
59
____1____: caused by nematode worms that block lymph flow __2__ lymph nodes.
1. Elephantiasis
| 2. Into
60
Heart
• In adult mammal, heart has 4 chambers
– Left & right atria (sing. atrium), left & right ventricles
• 4 chambers arranged into 2 separate circuits
– Pulmonary circuit: to and from lungs
– Systemic circuit: to and from tissues of body
• Typically drawn as if viewed from ventral surface
– i.e., as if organism is lying on its back, head end up
– So left side of drawing is right side of heart, & vice versa
– Like shaking hands with someone
61
The _______ circuit pumps blood to and from the lungs
Pulmonary
62
The _______ circuit pumps blood to and from the tissues of the body
Systemic
63
Heart
| • Blood flow through heart
– DEOXYGENATED blood from major veins (superior & inferior vena cavae) enters right atrium
– Contraction of RIGHT atrium delivers blood through RIGHT AV (AtrioVentricular or TRIcuspid) valve into RIGHT ventricle
– Contraction of RIGHT ventricle delivers blood through PULMONARY semilunar valve into pulmonary ARTERY and hence to lungs
• Pulmonary artery carries DEOXYGENATED blood
– Blood returns to heart from lungs via pulmonary VEIN
• Pulmonary vein carries OXYGENATED blood
– Pulmonary vein delivers blood to LEFT atrium
64
Heart
• Blood flow through heart
- "2nd half" starting when pulmonary vein delivers blood to LEFT atrium
– Contraction of LEFT atrium delivers blood through LEFT
AV (bicuspid or mitral) valve into LEFT ventricle
– Contraction of LEFT ventricle delivers blood through AORTIC semilunar valve to the aorta (dorsal aorta) and hence to tissues of the body
• Both atria fill and contract in UNISON, as do both ventricles
• Ventricles are STRONGER pumps than atria so are thicker muscle
• LEFT ventricle is STRONGER pump than right (pumping to entire body vs. lungs) so is thicker
65
What type of blood enters the right atrium from the major veins (superior & inferior vena cavae)?
Deoxygenated
66
I am blood in the RIGHT ventricle of the heart, where did I just come from and through what valve?
Came from the RIGHT atrium and passed through the RIGHT AtrioVentricular or TRIcuspid valve.
67
True or False: Contraction of the RIGHT ventricle delivers blood through the AORTIC semilunar valve into the pulmonary VEINS.
False, Contraction of the RIGHT ventricle delivers blood through the PULMONARY semilunar valve into the pulmonary ARTERY.
68
True or False: All veins carry deoxygenated blood, while all arteries carry oxygenated blood.
False, Pulmonary artery carries deoxygenated blood, while the pulmonary vein carries oxygenated blood. All other veins and arteries are the opposite.
69
The pulmonary vein delivers __1__ blood into the __2__ atrium.
1. Oxygenated
| 2. Left
70
True or False: Contraction of LEFT atrium delivers blood through LEFT AV (bicuspid or mitral) valve into LEFT ventricle
True
71
Contraction of __1__ ventricle delivers blood through __2__ semilunar valve to the aorta (dorsal aorta) and hence to tissues of the body
1. Left
| 2. Aortic
72
True or False: Both atria fill and contract in UNISON, while both ventricles contract one after the other
False, both atria fill and contract in UNISON, as do both ventricles.
73
Artia are __1__ (stronger/weaker) pumps than ventricles so are __2__ (thinner/thicker) muscle
1. Weaker
| 2. Thinner
74
True or False :LEFT ventricle is STRONGER pump than RIGHT (pumping to entire body vs. lungs) so is THICKER
True
75
Heart
| • Systole/Diastole
• Heart contraction is called SYSTOLE and relaxation is called DIASTOLE
– So there is atrial systole/diastole and ventricular systole/diastole
76
Heart contraction is called _____
Systole ("syst" rhymes with "fist")
77
Heart relaxation is called _____
Diastole
78
Heart
| • Ventricular diastole
• During ventricular diastole (relaxation)
– Ventricles rebound, semilunar valves close (2nd heart sound, “dup”) preventing backflow into ventricles
– Atria fill, pressure there rises, AV valves open
– Blood moves from atria into ventricles
– Atria then contract, forcing more blood into ventricles
– Then a short pause
79
Heart
| • Ventricular systole
• During ventricular systole (contraction)
– Pressure in ventricles rises
– AV valves close (1st heart sound, “lub”), preventing backflow into atria
– Semilunar valves open
– Blood is forced into the ...
• pulmonary artery (from right ventricle) and
• the aorta (from left ventricle)
80
During ventricular diastole (relaxation): ventricles rebound, semilunar valves close, producing ___ (first/second) heart sound (“dup”), preventing backflow into ventricles
Second
81
During ventricular systole (contraction): AV valves close, producing ___ (first/second) heart sound (“lub”), preventing backflow into atria
First
82
Heart
• Electrical coordination of heart contraction
-Part 1
– Vertebrate cardiac muscle is myogenic
• i.e., it has an intrinsic contractile rhythm
– In mammal heart, the primary source of this rhythmicity is the sinoatrial node (SA node)
• a.k.a. “pacemaker”
• Located in wall of right atrium
• Specialized cardiac muscle cells
• Intrinsic rhythmicity is ~100 X per minute
• Derived from sinus venosus of heart of fish
83
Vertebrate cardiac muscle is ______
Myogenic
84
In mammal heart, the primary source of the intrinsic contractile rhythm is the....
Sinoatrial node (SA node)
85
The sinoatrial node (SA node) is also know as the __1__ and is located in the wall of the __2__ atrium
1. "Pacemaker"
| 2. Right
86
The sinoatrial node produces an intrinsic rhythmicity ~___ times per minute
~100 X per minute
87
Heart
• Electrical coordination of heart contraction
-Part 2
– Wave of depolarization originates in pacemaker (SA node)
• Spreads through right and left atria via gap junctions
• Right and left atria contract nearly simultaneously
– Connective tissue between atria and ventricles stops spread of contraction
– Spread is continued by atrioventricular (AV) “node”
• In interatrial septum just above right AV (tricuspid) valve
• AV node introduces a slight delay (~0.1 s), allows atria to complete contraction and delivery of blood to ventricles
88
Heart
• Electrical coordination of heart contraction
-Part 3
– Contraction SIGNAL continued by AV bundle and Purkinje fibers to bottom of heart
• Signal transmitted down interventricular septum to muscle cells and “bottom” of ventricles
• AV bundle a.k.a. “bundle of His” (“hiss”)
• Fibers specialized for conduction of signal, much faster than muscle to muscle
– So, VENTRICULAR contraction begins at bottom and proceeds up the ventricles, squeezing blood into the arteries (pulmonary & aorta) at “top” of ventricles !
– Time elapsed from initiation (depolarization) by SA node until depolarization of last ventricular cardiac muscle cell is about 0.22 sec.
89
Ventricular contraction begins at the __1__ (top/bottom) and proceeds __2__ (up/down) the ventricles, squeezing blood into the arteries (pulmonary & aorta) at "__3__" (top/bottom) of ventricles.
1. Bottom
2. Up
3. Top
90
Time elapsed from initiation (depolarization) by SA node until depolarization of last ventricular cardiac muscle cell is about ____ seconds
0.22 seconds
91
Heart
| • Electrocardiogram
– Abbreviated ECG or EKG
– Measures electrical signals from heart as a whole
– Typical pattern is 3 distinguishable DEFLECTION WAVES
– P wave
• Atrial contraction (depolarization)
– QRS wave
• Ventricular contraction (depolarization)
– T wave
• Ventricular recovery (repolarization)
• Atrial recovery is obscured by QRS wave
– Pattern can be used to identify diseased or damaged hearts
92
ECG measures electrical signals from heart as a whole, the typical pattern is 3 distinguishable _____ ____
Deflection waves
93
True or False: The P wave represents ventricular contraction (depolarization)
False, The P wave represents ATRIAL contraction (depolarization)
94
True or False: The QRS wave represents ventricular contraction (repolarization)
Fasle, The P wave represents ventricular contraction (DEPOLARIZATION)
95
The T wave represents ventricular ______
Recovery (repolarization)
96
ECG can be used to identify __1__ or __2__ hearts
1. Diseased
2. Damaged
- Don't need to know specifics
97
Heart
| • Central nervous system control
– Property of autonomic nervous system
• Cardiac control centers in medulla oblongata
• Sympathetic “cardioacceleratory center”
• Parasympathetic “cardioinhibitory center”
– At rest, dominant effect of autonomic control is inhibitory
• Cut innervation (vagus nerve, parasympathetic) results in prompt rise in heart rate by about 25 beats/min, to about 100 beats/min (intrinsic rate of SA node)
98
Autonomic control
• Sympathetic “cardioacceleratory center”
– Connects to SA & AV nodes and ventricle muscle
– Responds to fright, anxiety, excitement, exercise
– From medulla via motor neurons down spinal cord to heart
– Neurotransmitter is norepinephrine
• Parasympathetic “cardioinhibitory
center”
– Connects to SA & AV nodes primarily
– Can respond to grief, severe depression
– From medulla via vagus nerve (cranial nerve X)
– Neurotransmitter is acetylcholine, hyperpolarizes membranes by opening K+ channels
99
The sympathetic nervous system is the "________ center"
| (cardio-acceeleratory/cardio-inhibitory), can responds to fright, aniexty, excitement, exercise.
Cardioacceleratory
100
The parasympathetic nervous system is the "________ center", can responds to grief, severe depression
(cardio-acceeleratory/cardio-inhibitory)
Cardioinhibitory
101
True or False: The neurotransmitter in the sympathetic nervous system is norepinephrine
True
102
True or False: The neurotransmitter in the parasympathetic nervous system is acetylcholine
True
