Final Exam Flashcards
1
Q
why is the fibrous skeleton critical?
A
The fibrous skeleton of the heart is critical for helping to maintain electrical isolation of the upper and lower chambers so that they contract and relax in turn during a single heartbeat
2
Q
are the valves and fibrous structure all part of the same skeleton? is there an electrical connection through the skeleton?
A
the heart valves and white fibrous structures supporting those valves are all part of the skeleton. the only electrical connection through the fibrous skeleton is via the AV node and the AV bundle.
3
Q
Explain the function and terminology for the heart valves
A
Atrioventricular Valves- divides the aorta from the ventricles
- Right AV valve=tricuspid valve
- Left AV valve=bicuspid valve=mitral
Semilunar Valves-divide the ventricles from the blood vessels
*Aortic semilunar valve-controls blood flow from Left ventricle to aorta
Pulmonary semilunar- valve controls blood flow from R ventricle to pulmonary trunk
4
Q
describe in order the pathway of blood through the heart.
A
- blood enters right atrium from superior and inferior venae cavae
- blood in right atrium flows through right AV valve into right ventricle
- contraction of right ventricle forces pulmonary valve open
- blood flows through pulmonary trunk
- blood is distributed by right and left pulmonary arteries to the lungs, where it unloads CO2 and loads O2
- blood returns from lungs via pulmonary veins to left atrium
- blood in left atrium flows through left AV valve into left ventricle
- contraction of left ventricle (simultaneous with step 3) forces aortic valve open
- blood flows through aortic valve into ascending aorta
- blood in aorta is distributed to every organ in the body where it unloads O2 and loads CO2
- blood returns to heart via venae cavae
5
Q
what is the importance of the chordae tendinae and the papillary muscles? what are their functions?
A
the chordae tendineae (tendinous cords) holding ends of AV valves to papillary muscles in the heart wall. these one way flap-type valves are seen throughout the cardiovascular system and help to maintain one-way-flow. Pressure will open them but shut them from the “flap” side. Pressure difference will either open or shut the valve depending on which side of the valve has higher pressure. the pressure in the left ventricle is so great during ventricular contraction that the tendinous cords and contraction of the papillary muscles are needed to prevent the valve flaps from being blown upwards into the atria
*if such and event occurs it is called mitral valve prolapes
6
Q
what are the layers and membranes of the heart in order from the outside in?
A
*Parietal Pericardium-lines pericardial cavity
*Parietal Cavity
*Visceral Pericardium- lines heart
*Myocardium-muscle
Endocardium-lines chambers
(Epicardium=visceral pericardium)
7
Q
is there a fluid that reduces friction that lies between the visceral pericardium and parietal pericardium?
A
yes, pericardial fluid fills the parietal cavity to reduce friction during contractions of the heart
8
Q
What makes up the heart wall specifically.
A
- endocardium
- myocardium
- epicardium
9
Q
what is the description of the endocardium and it’s functions?
A
- Lines chambers
- helps prevent clotting
- continuous with endothelium of blood vessels
10
Q
what is the description of the myocardium and it’s functions?
A
- heart muscle
- electrically connected muscle cells & some special fibers for conducting electrical current
- contains connective tissue fiber skeleton (anchors reinforces, supports & electrically isolates in places)
11
Q
what is the description of the epicardium and it’s functions?
A
- thin outer layer of mesothelium (membrane)
- some adipocytes; simple squamous epithelium & areolar tissue (general term for connective, reticular, and adipose tissue)
12
Q
are there intercalated cardiac muscles that provide an electric connection?
A
yes, intercalated discs containing desmosomes & gap junctions which provide electrical connections between adjacent cells
13
Q
what does the special conducting system of the heart do and what does it include?
A
Coordinates and conducts electrical activity through the hear, thus coordinating sequence and timing of contraction for arterial and ventricular muscle cells.
- includes:
- Pace maker cells- sinoatrial (SA) node, atrioventricular node and atrioventricular bundle (bundle of his)
- other conducting cells and fibers -right and left bundle branches and purkinje fibers
14
Q
Explain the difference in the action potentials of the conducting system and pace maker cells
A
there are 2 types of action potentials generated in different cell types within this system
the first type is seen in specialized cells that are called pacemaker cells. they are modified muscle cells in specific locations. their action potential has a different shape from the other action potentials in the heart because the initial rising phase is generated by a voltage gated calcium channel rather than by voltage gated sodium channels.
*pacemaker cells do not have a membrane potential. they have pacemaker potentials
15
Q
what is a pacemaker potential?
A
the pacemaker potential is slowly depolarizing baseline membrane potential that eventually reaches threshold triggering an action potential
16
Q
What is the combination of gates that work sequentially to produce a drifting baseline membrane potential (pacemaker potential)?
A
It is generated by a combination of calcium sodium and potassium channels that work sequentially to generate this drifting baseline membrane potential know as the pacemaker potential.
17
Q
where are pacemaker cells located?
A
pacemaker cells are located in the (SA) node the AV node and the uppermost part of the bundle of his (AV bundle)
18
Q
do the bundle branches and purkinje fibers have a resting membrane potential?
A
Yes they exhibit resting membrane potentials seen in cardiac muscle cells
19
Q
do the resting membrane potentials of purkinje fibers and bundle branches still differ from conventional action/resting potentials?
A
these are still different from the action potentials involved with skeletal muscles and neurons because it involves a voltage gated calcium channel in addition to the normal voltage-gated sodium channel and voltage-gated potassium channel.
20
Q
what is the sequence of excitation of cells? How many steps are there and name them
A
The cells of the heart are electrically connected via gap junctions such tat the cells will fire AP's in a specific sequence. 1. SA node 2 Atrial muscle cells 3. AV node 4. AV bundle (bundle of his) 5. R and L bundle branches 6. Purkinje fibers 7. ventricular muscle fibers
21
Q
Are pacemakers different from myoblasts?
A
Pacemaker cells and the other cells of the cardiac conduction system are cells that differentiate from other myoblasts in specific locations as heart develops.
22
Q
what makes them different?
A
They express channels that are not found in other cells making them able to produce a pacemaker potential, depolarizing baseline that triggers the action potentials
23
Q
What makes pacemaker cells unusual?
A
Some of the conducting cells are pacemaker cells
-capable of spontaneously depolarizing over threshold (pacemaker potential)
-action potentials generated by different currents and channels than cardiac muscle cells
24
Q
what does permeability mean?
A
a decrease in permeability means a channel closed
an increase in permeability means a channel opened.
25
Explain in detail and sequential order the action potential of a ventricular cardiocyte (myocyte).
1. Voltage-gated Na+ channels open
2. Na+ inflow depolarizes the membrane and triggers the opening of still more Na+ channels creating a positive feedback cycle and a rapidly rising membrane voltage.
3. Na+ channels close when the cell depolarizes and the voltage peaks at nearly +30 mv
4. Ca++ entering through slow Ca++ channels prolongs depolarization of membrane, creating a plateau. plateau falls slightly because some K+ leakage, but most K+ channels remain closed until end of plateau
5. Ca++ channels close and Ca++ is transported out of cell. K+ channels open, and rapid K+ outflow returns membrane to its resting potential
26
what is important about a prolonged calcium influx during the plateau phase?
Calcium influx occurring during the plateau phase is needed to bind to troponin to allow muscle contraction in heart muscle cells, some calcium comes form the sarcoplasmic reticulum, but much of it comes in via these voltage-gated calcium channels. longer action potentials with more calcium influx can actually lead to stronger longer contractions of heart muscle.
*contraction starts a little after the action potential begins and stops about the same time the action potential ends
27
what are the basic physics of blood flow?
* Flow (F)
* Pressure at 2 points (P1 & P2), difference delta
* Resistance (R)
* F=deltaP/R
28
What are the principles of volume?
Pressure and flow. fluid doesn't change its volume under normal conditions found in the body
29
When pressure is applied what happens
when pressure is applied that pressure is increased within the fluid causing it to generate force (pressure) on the walls of its container
30
When pressure is present what are the actions that take place?
When pressure in one place (P1) is greater than pressure in (P2) the fluid will flow form point 1 to point 2
31
The amount of flow is a function of what?
The amount of flow is a function of the difference between the pressures at each point (deltaP) and the resistance to flow inherent to the container or tube.
32
other than a thick viscous fluid what else resists movement?
the sides of the chamber or tube create friction or turbulence that also adds to resistance
33
what are the cardiac phases?
*ventricular filling (diastole)
-passive
-active=atrial systole
*ventricular contraction (systole)
-isovolumetric contraction -ventricles contract
to raise pressure
-ejection- pressure high enough to open valves,
blood moves out
*isovolumetric relaxation (early part of diastole)
-ventricles relax after semilunar valve shuts (all
valves closed)
-pressure decreasing until AV valve opens
-volume in ventricle =end systole volume
34
what happens to valves during the sounds 1-3?
S1="lubb" closing of AV valves
S2="dub" closing of semilunar valves
S3=heard during ventricular filling
35
what does the frank starling mechanism posit? (sterlings law of the heart)
increased venous return=increased stroke volume
*the increase in stroke volume is greater than the increase in venous return ( because of EDV-end diastolic volume)
36
what are the events that lead to the starling law of the heart?
the frank starling principle is due to both increase in volume of blood returned to the heart (increased veous return and EDV) and due to increased force of contraction of the ventricle wall (decreased ESV)
on is a direct result of the increased stretch in the ventricular wall. The increased stretch leads an elastic recoil that helps increase force, and this stretch also leads to a more favorable length-tension relationship for cardiac muscle, which also helps increase force generated by ventricular myocyte.
37
what does sympathetic activity and innervation dot to the heart? what are two hormones involved?
Sympathetic activity and innervation (norepinephrine, epinephrine) speeds up the heart and increases the force of contraction of the heart.
38
what does the parasympathetic innervation do to the heart rate? name a hormone and receptor?
parasympathetic innervation (acetylcholine onto a muscarinic cholinergic receptor) will slow down the heart rate.
39
how do alterations in the heart rate happen?
alterations in the heart rate happen by increasing the speed of the pacemaker potential or decreasing the speed of the pacemaker potential.
40
what is the heart rate of a heart that doesn't receive innervation?
the rate of a heart that does not receive innervation is about 100 bpm. the heart is said to have a parasympathetic tone (e.g. avg bpm 72)
41
What do some of the most common types of signaling pathways include?
A protein known as the G-Protein
42
Why are G-proteins called G-proteins? Also, what do they do?
These proteins are called G-proteins because they bind and break down a GTP molecule as they perform their action, much like myosin binds and breaks down ATP as it helps create muscle contractions.
43
Receptors that have G-Protein involved in their signaling pathway are called what?
G-Protein Coupled Receptors or GPCRs
44
Do G-proteins utilize a second messenger during their signaling pathway?
Most G-proteins utilize a second messenger, a chemical whose concentration rises within the cell cytosol so that it will bind and activate another protein such as an enzyme or calmodulin.
45
Calmodulin
An intracellular protein that binds calcium ions and mediates many of the second messenger effects of calcium.
46
Second messenger pathways
* cAMP (cyclic adenosine monophosphate)
* Calcium
* Inosital trisphosphate (IP3)
* Diacylglycerol
* cGMP (cyclic guanosine monophosphate)
47
What is the time to activity in the target cell? How long does it take to effect things?
* Cell membrane receptors = seconds to minutes
* Intracellular receptors= hours to days
! Water soluble hormones will only use cell membrane receptors !
! Lipid Soluble (hydrophobic) hormones generally have intracellular receptors with some cell membrane receptors !
48
what do kinase enzymes do?
they attach phosphate groups
49
What are some divisions of the ANS (Autonomic Nervous System)? Also< what are the hormones and receptors responsible for carrying out some of the ANSs functions
* Sympathetic Division (Fight/Flight/Fright)
- Epinephrine (hormone from adrenal modulla)
- Norepinephrine- sympathetic fibers
-Adrenergic receptors on target cells
*Alpha receptors - contract smooth muscle
usually inhibit hormone secretion
*Beta receptors-relax smooth muscle
usually stimulates hormone secretion
50
Is the sympathetic division of the ANS needed for emergency situations?
The sympathetic division, of the ANS, generates the reactions known as fight, fright, flight in an extreme activation of the system.
51
What other division of the ANS does the sympathetic division work with to achieve homeostasis?
The sympathetic division of the ANS works every minute of every day in balance with the parasympathetic division to regulate homeostasis and cycles of activity and rest in your body.
52
What occurs in the body during an extreme activation of the sympathetic division of the ANS?
-increased blood pressure
-increased heart rate
-halted urine production
-halted digestion
-conservation of fluids and energy
-blood directed away form kidney and intestines
(vasoconstriction)
-blood directed toward skeletal muscles
(vasodilation)
-dilated pupils and relaxed ciliary muscles for
flattened lenses.
(enemy detection)
53
What are the hormones and receptors involved?
| What are some characteristics of a parasympathetic activation?
Relax and take care of living
* Parasympathetic Division
- Acetycholine for parasympathetic fibers
- Muscarinic cholinergic receptors
- Cleaning blood
- making urine
- digesting food
! during sex the body is relaxed and excited parasympathetic and sympathetic divisions !
54
what are the characteristics of arteries
away from heart
- aorta
- arteries
* large, medium, small
- arterioles
55
What do capillaries do
exchange
56
what are the characteristics of veins
toward heart
- venules
- veins-large, medium, small
- vina cava -inferior and superior
57
what do large arteries tend to have?
| what do medium/small arteries have?
very thick internal elastic layer while some medium/smaller arteries have a proportionally large muscular layer
58
why do veins have a larger radius relative to arteries at same distance from heart?
it allows for similar flow in veins with lower pressure and velocity than the matched artery
59
what is involved in controlling the perfusion of capillary eds, local and systemic?
local controls
- oxygen
- carbon dioxide
- K+
- nitric oxide
systemic control
- norepinephrine
- epinephrine
- vasopressin (ADH)
- angiotensin
60
define perfusion.
blood flowing into capillary beds
61
are precapillary sphincters involved in control of blood flow?
precapillary sphincters control the flow of blood into a capillary bed thus controlling the level of perfusion of that bed and the tissue it supplies.
62
what is a metarteriole?
a metarteriole is a more direct passage through the capillary bed
63
with less perfusion do you get more blood flow through the metarteriole?
with less perfusion more blood would flow through the metarteriole
64
an arteriovenous anastomosis is a direct connection that serves for a bypass for what?
an arteriovenous anastomosis is a direct connection between the arteriole and venule that serve as a bypass for the capillary bed
65
explain what regulates the level of perfusion at a local level?
the level of perfusion of capillary beds is under primarily local controls from chemical signals, through sympathetic signals (nerves and hormones) can regulate perfusion in some situations.
66
list the local effectors of vasodilation and vasoconstriction
vasodilators
- low O2 and or high CO2
- lactic acid
- nitric oxide (NO) from endothelium
- high K+ or H+ in interstitial fluid
- local inflammation (e.g. histamine, NO)
vasoconstrictors
- prostaglandins
- throwboxanes
- endothelin
67
what is the endothelin and what produces it as well as releases it?
endothelin is a chemical messenger produced and released by endothelium
68
is adenosine a vasodilator?
adenosine is also listed as a vasodilator it may by an important local vasodilator for the heart
69
where are baroreceptors and chemoreceptors located?
baroreceptors and chemoreceptors in the arteries superior to the heart
70
specifically where are baroreceptors and what are their functions?
there are baroreceptors )fundamentally stretch receptors) in the aortic arch and carotid sinuses.
- they trach blood pressure for flow of blood to
the body (aortic arch) and brain (carotid sinus)
71
what do chemoreceptors form?
there are chemoreceptor cells clustered to form aortic bodies (where corotids branch from aorta) and carotid bodies (where internal and external carotids branch )
peripheral chemoreceptors in these blood vessels detect oxygen, carbon dioxide and PH levels in the blood
72
what do the peripheral chemoreceptors detect in the blood?
peripheral chemoreceptors in these blood vessels detect oxygen, carbon dioxide and PH levels in the blood
-the pressure, blood gas and PH information is
all transmitted to the brain stem via the vagus
(X) and glossopharngeal (IX) cranial nerves
73
what can these receptors affect? how does it affect it?
signals from these receptors can affect the ananomic nervous system drive to the heart to increase blood pressure (baroreceptors) and respiratory rythms (chemoreceptors) to keep blood gases and PH within normal reange
74
what are the 3 main types of capillaries?
continuous capillaries
fenestrated capillaries
sinusoids
75
describe continuous capillaries.
structure of a continuous capillary: small gaps between endothelial cells called intercellular clefts that let fluid in and out of the capillary
*specialized continuous capillaries in the brain have tight junctions between epithelial cells rather than clefts to form the blood-brain barrier
76
describe fenestrated capillaries
structure of fenestrated capillaries: capillaries with pores that span the epithelial cells
-these make these capillaries more porous than
continuous capillaries
-found in choroid plexus of brain, most classical
endocrine organs, intestines and kidneys
77
describe sinusoids
structure of sinusoids: flattened or irregularly shaped with large gaps between adjacent epithelial cells
-allows for greater exchange with surrounding
tissues
-found in liver spleen and bonemarrow
78
do arteries act as a reserve for pressure?
| do veins act as a reserve for blood volume?
Arteries act as a reserve of pressure within the cardiovascular system, but veins act as reserve for blood volume
79
what has to happen for your blood to start circulating faster?
when you need to get blood circulating faster constriction of larger veins will greatly increase venous return helping to boost cardiac output
80
what portion of the nervous system controls vasoconstriction of veins?
sympathetic innervation controls the vasoconstriction of veins
81
do most tissues have a simple pathway?
most tissue have the simple pathway
82
is there a portal system in the hypothalamus and pituitary?
there is a portal system in the hypothalamus and pituitary
83
what is the portal system between the liver and intestine called?
the hepatic portal system
84
where are AV shunts most commonly found?
AV shunts are most common in fingers and toes for conserving heart
85
does the blood supply to and from the brain have lots of anastomoses?
the blood supply to and from the brain has lots of anastomoses
86
what are the differences in arterial and venous systemic circulation?
Arterial
- conduit between heart and capillaries
- pressure reservoir
- damp oscillations in pressure and flow
- control distribution to capillary networks
Venous side
- conduit between capillaries and heart
- volume reservoir
- low pressure aided by various mechanisms
* one way valves
* skeletal muscle pumping
* respiratory pumping
87
Is TPR affected by arterial diameter?
Total Paripheral Resistance (TPR)
| Arteriole diameter -big factor in TPR
88
why are baroreceptors called different things according to where they are found?
baroreceptors in the arterial side monitor blood pressure and sometimes are called high pressure baroreceptors while those in the venous side (primarily right atrium and a few large veins ) are called low pressure baroreceptors.
89
describe pressur flow and resistance
Blood flow (F)- is always from an area of higher pressure to lower pressure
Hydrostatic pressure (P)-is the pressure exerted by any fluid
resistance (R)- is the measure of forces tat impede flow
90
what is the equation fro flow?
F=^(greek delta)P/R
91
name and describe the different pressures that arise in the body?
```
blood pressure
capillary pressure
venous pressure
pulse pressure
mean arterial pressure (MAP)
```
92
how is blood pressure usually reported?
usually reported as arterial pressure at about level of heart
-systolic BP/diastolic BP
93
what is another name for capillary pressure and what is it a major factor in determining?
capillary pressure of capillary hydrostatic pressure (CHP)-is a major factor in determining the level of exchange of fluids with surrounding tissue
94
Is venous pressure usually low?
venous pressure is usually quite low; this is why there are additional mechanisms to help maintain good flow within the venous side of the systemic circuit
95
what is pulse pressure?
pulse pressure is the difference between systolic and diastolic pressure. It is a crude measure of total peripheral resistance and compliance (elasticity) of blood vessels.
96
what is MAP a measurement of?
mean arterial pressure is a measurement of the average force behind the blood flow withing the arterial side of the systemic circuit
97
Is MAP and indicator of something?
it is a good indicator of whether or not there is sufficient force to get a adequate brain blood flow and of the degree of stimulation of baroreceptors that signal blood pressure to the ANS
98
how is MAN equated?
MAP=DP + 1/3 (SP-DP)
MAP (mean arteriole pressure)
DP (diastolic pressure)
SP (systolic pressure)
99
when does BP fall?
| when is BP the lowest?
- Pressure falls as blood flows through the circuit
| - lowest pressure as blood re-enters the heart (superior vena cava)
100
what type of blood vessel has the greatest ability to change radius?
arterioles have the greatest ability to change radius of all the blood vessels, and thus, their changes usually determine the minute to minute changes in (TPR) total periperal resistance
101
is the blood flow the same at all points in the systemic system ?
does velocity slow at any point?
- blood flow same at all points in system
- velocity slows in capillaries
- small readius
- many capillaries
102
where is blood pressure the slowest?
blood flow is the slowest in the caillaries
103
do capillaries have a large cross section?
capillaries actually has the largest cross sectional area of any point within the circuit
104
flow is the result of differences in pressures at 2 points?
Flow (F)=P(point 1)------P(point 2)
| P=pressure
105
is flow inversely related to resistance?
Flow(F) is inversely related t resistance
106
is there a positive correlation between viscosity and resistance?
yes, Resistance = viscosity ^ = Resistance ^
107
is there an inverse relationship with resistance and vessel diameter?
is there an inverse relationship with resistance and vessel diameter?
108
what can affect cardiac output?
Cardiac output
| -ANS (and epinephrine)
109
what affects blood volume?
Blood volume
- hormones
- ANS
110
what has a affect on arteriole diameter?
Arteriole diameter-local/systemic
- ANS
- hormones - vasopressin, angiotensin
- local signals and chemical messengers
111
what do the hormones vasopressin and angiotensin do?
vasopressin (AVP or ADH), and angiotensin are hormones that affect both blood voluje and directly alter blood pressure through vasoconstriction in some blood vessels
112
aldosterone and natriuretic peptides regulate what?
aldosterone and natriuretic peptides (ANP & BNP) are additional regulators of blood volume
113
adrenergic chemical messenger stimulate receptors that do what?
beta adrenergic receptors cause vasodilation
| alpha adrenergic receptors cause vasoconstriction
114
cardio vascular regulation is controlled by what?
Neural mechanisms
endocrine
Autoregulation
115
how does the neural mechanisms affect cardio vascular regulation?
neural mechanisms - ANS
- systemically or
- within specific tissues/organs
116
how does the endocrine system affect cardio vascular regulation?
endocrine
-direct via ANS (epiphrine) or other hormones (e.g.
thyroid hormone)
-indirect via regulation of blood volume
117
how does autoregulation factors affect cardio vascular regulation?
autoregulation
| -with local factors e.g. 02 chemical messengers
118
where are the sensors found that mediate autoregulation?
Sensors tat mediate autoregulation are found locally within blood vessel walls
119
what are the sensors that regulate neural control?
sensors that regulate neural control are baroreceptors (detect pressure) and chemoreceptors (detect oxygen, carbon dioxide and PH levels)
120
what is the process involved in the negative feedback control of blood pressure?
high blood pressure activates baroreceptors in the aortic arch and corotid sinus.
this triggers decreased sympathetic activity at the sinoatrial node ( SA node AKA pacemaker cell) of the heart and increased parasympathetic activity at the SA node. The resulting decrease in cardiac output reduces blood pressure.
121
what is the sequential order of lowering BP?
1.Elevated BP
2.Causes arteries to stretch
3.baroreceptors detect pressure change and begin increasing their firing rate
4.cardioinhibitory neurons are stimulated
5.increased vagal tone
6.reduced heart rate
7. reduced BP
Simultaneously starting at 4.
4.vasomotor center is inhibited
5.reduced sympathetic tone
6.reduced vasomotor tone
7.Vasodilation
8.reduced BP
122
is redirection of blood flow in response to changing metabolic needs typically mediated by local and systemic changes?
typically changes in blood flow are mediated by both local and systemic factors
123
does digestion increase blood flow primarily through local signals leading to vasodialation?
digestion would increase blood flow to the intestines primarily through local signals leading to vasodilation as food and chyme moved through the digestive track.
124
does increased sympathetic activity as well as local changes affect blood flow to muscles?
increased sympathetic activity as well as local changes in oxygen and carbon dioxide levels around muscles will increase blood flow to skeletal muscles during exercise
125
what are the responses in vasodilation, venous return, cardiac output and stress response with light exercising?
* light exercise
- extensive vasodilation of skeletal muscle (O2)
- venous return increases
* skeletal muscle pumping
* respiratory pumping
- cardiac output increases
* frank starling
* sympathetic stimulation
126
what are the responses in vasodilation, venous return, cardiac output and stress response with heavey exercise?
* Heavy exercise
- stress response
* blood flow shifts
* large increase in heart rate and BP
127
how does capillary filtration and reabsorption occur?
exchange of fluids and dissolved substances occurs in capillary beds because of capillary hydrostatic pressure pushing fluid out and colloidial osmotic pressure pulling fluid into the capillary
128
what is the term for the difference in osmotic pressure and hydrostatic pressure?
the difference between these 2 pressures is called the net filtration pressure
129
is the net filtration pressure positive on the end of arterials?
the net filtration pressure is positive on the arterial end of the capillary causing fluid to move out
130
is the net filtration pressure negative on the venous side?
it is negative on the venous side causing fluid to come into the capillary
131
what is colloidal osmotic pressure usually generated by? what is this pressure sometimes called?
colloidal osmotic pressure is the osmotic pressure of blood generated by large blood proteins, primarily albumins. It is sometimes called on oncotic pressure
132
waht are the mechanisms aiding venous blood flow
one way valves
skeletal muscles pumping
respiratory pumping
133
can deep breathing help bring blood from the legs back to the heart?
the peristaltic pumping action on the outside of the inferior vena cava caused by the pressure changes inside the thoracic cavity as you breathe can help to draw blood up form the legs and return it to the heart (deep breathing)
134
what are the components of whole blood?
```
plasma
formed elements (cells)
```
135
what does plasma contain?
hormones, ions, glucose, lipids, clotting proteins etc
136
how many types of formed elements are there?
erythrocytes (RBCs)
leukocytes (WBCs)
platelets
137
how many and what type of leukocytes are present in whole blood?
```
Granulocytes
-Neutrophils (C)
-Eosinophils (acidophils P)
-Basophils (B)
Agranulocytes
-Lymphocytes
-monocytes
```
138
what does the lymphocytes include?
T,B and plasma cells
139
are monocytes precursors?
monocytes are precursors to macrophages
140
what are the characteristics of RBCs?
* most abundant cell in blood (37%-54%)
* Biconcave disc
* Lose organelles except cytoskeleton
141
what is the RBC count?
concentration of RBCs/vol
142
what are some attributes of a biconcave disc?
* large surface to volume ratio
* allows cells to stack
* allows cells to bend and flex
143
What does hematocrit include?
includes all the formed elements
144
are WBCs and platelets a large % of whole blood?
the wbc and platelets are a very small % of the cells in whole blood
145
what is at the top of whole blood following centrifugation of blood?
it separates to form the "buffy coat" at the top of the formed elements ( the wbcs and the platelets)
146
what do mature rbcs contain?
rbcs contain lots of hemoglobin for carrying oxygen, some glycolytic enzymes, but not much else
147
how long do rbcs last in circulation?
mature rbcs last about 120 days (4 months) in circulation.
148
where do rbcs degrade?
generally they are trapped in the spleen or the liver where they degrade.
149
how long does it take for a mature rbc to form?
about 8 weeks to make new rbcs from first stem cell division to mature rbc
150
what is the structure of hemoglobin?
-4 subunits
*2 pair identical subunits(a&b)
-Heme group at center with
Fe (iro
151
what is its function? (hemoglobin)
* function
- oxyhemoglobin
- deoxyhemoglobin
- carbaminohemoglobin
152
where does O2 bind to hemoglobin?
the O2 binds to the iron of the heme group in the center of each subunit
153
how is fetal hemoglobin different form adult hemoglobin and how is its function different?
hemoglobin in a fetus uses a different gene for 2 of the subunits resulting in a form of hemoglobin that binds oxygen more easily and tightly than normal adult hemoglobin
154
what is the capacity of hemoglobin?
each hemoglobin molecule can carry 4 molecules or 8 atoms of oxygen
155
what is a reticulocyte?
reticulocyte-immature rbcs that have just entered circulation from the bone marrow, but have not yet lost all their endoplasmic reticulum.
156
the amount of reticulocytes are a good indication of what?
their number is a good indication of recent rbc synthesis
157
can wbcs leave the bloodstream?
yes all can leave through diapedesis
158
what does thrombopoietin stimulate?
thrombopoietin stimulates maturation of Tcells
159
what is bilirubin?
bilirubin is a bile pigment created by the breakdown of hemoglobin and secreted into bile by the liver
160
do men have more rbcs than women?
yes, because testosterone stimulates erythropoietin production which stimulates erythropoiesis (production of rbcs) thus given men more oxygen carrying capacity than women.
161
what is required for erythropoiesis?
```
erythropoiesis
*red marrow
*timing
*requires
-amino acids
-iron (Fe)
-B12 B6 and folic acid
*erythropoieitin
* hemocytoblast to myeloid
stem cell to erythroblast
```
162
how long does erythropoiesis take?
-8 weeks total
-3-5 days (ECFU
to reticulocyte)
-2 day (reticulocyte to RBC)
163
what is another name for red bone marrow?
myeloid tissue
164
where is red marrow found?
red marrow is located in the axial skeleton except for the skull (adults), and it is also found in the proximal head of the femur and humorous
165
what are hemoblast and what can they do?
hemoblasts (bone marrow stem cells) can differentiate into myeloid stem cells or lymphoid stem cells
166
what are myeloid stem cells?
myeloid stem cells can divide to produce cells that will eventually lead to the formation of rbcs and several classes of wbc
167
what are the steps in rbc breakdown
* trapping in spleen and liver
* hemolysis and phagocytosis
* proteins lysed and recycled
* heme unit broken down into fe2 and billiverdin
* billiverdin converted to bilirubin
* bilirubin transported to liver and excreted in bile
168
what are some reasons one would have inadequate hemoglobin?
* proximal causes
- low hematocrit
- low hemoglobin/erythrocyte
* ultimate causes
- blood loss
- diet
- bone marrow (cancer/chemotherapy)
- disease (e.g. sickle cell anemia)
169
what is pernicious anemia?
lack of B12
170
what is Polycythemia?
too many RBCs
171
what is Anemia?
lack of oxygen carrying capacity whether due to lack of rbc or a lack of hemoglobin
172
what are the proteins for ABO
- A version (antigenic)
- B version (antigenic)
- O version (not antigentic)
173
what does antigenic mean?
if a substance is introduced into the body and it stimulates the production of antibodies then it is deemed antigenic
174
Is the "D" protein in RH blood group antigenic
yes, "D" is antigenic
175
does the blood type indicate the type of protein on the RBC?
yes, type indicates protein type
176
what is the transfusion rule?
don't give anyone an antigen that they don't have
177
what does the blood group equal?
a blood group equals a locus (gene location in DNA)
178
how many alleles can a you have at a location in any one person?
you an lonly have 2 alleles (version of a gene) at that location in any one person
179
how many alleles do the ABO blood group have?
for the ABO blood group there are 3 possible alleles, A,B, and O
180
are A&B co-dominant?
yes
181
is "O" recessive? is it the most common?
"O" is recessive but is the most common blood type in the world
182
how many alleles does RH or "D" blood group have?
RH or "D" blood group has only 2 alleles
183
what does RH stand for?
Rhesus (REE-SUS)
| *comes from the Rhesus Macaque (MA-CAC) a monkey native to asia
184
if "D" protein is present what does it equal?
if "D" protein is present it equals +
185
If "D" protein is not present what does it equal?
If "D" protein is not present it equals -
186
if you have two alleles with no "D" (RH) what is the charge?
you have to have two negatives in order to have RH negative (D-)
187
if you have "D" protein on one allele and none on the other what is the charge?
if you have one positive and one negative your RH is positive (D+)
188
does agglutination cause clumps of cells to form?
the binding of antibodies to multiple RBCs leads to the formation of large clumps of cells
189
what happens when antibodies recognize foreign proteins on RBC?
antibodies recognize foreign proteins on the surface of the RBC and bind to it
190
when antibodies bind to RBCs do to foreign proteins what does this represent?
this initiates immune system responses that lead to breaking of the RBC, which is called hemolysis
191
what does agglutination indicate?
agglutination indicates presence of one of the proteins
192
can a pregnant RH- mother develop antibodies in response to her RH+ fetus?
if an RH- mother gestates an Rh + fetus, she can develop antibodies to the child's D protein
193
what produces platelets?
megakayocytes
194
what is involved in hemostasis?
* Vascular spasm
* Platelet pug formation
* Coagulation-clot formation
195
what is the opposite of hemostasis?
hemorrhage
196
what is involved in platelet plug formation?
adhesion
aggregation
plug
197
is response to an injured blood vessel hemostasis?
hemostasis is the response to an injured blood vessel
198
when damage to blood vessel endothelium happens release of chemical messengers trigger what?
damage to blood vessel endothelium that exposes underlying collagen fibers will begin the release of many different chemical messengers that will trigger hemostasis, immune system activity and tissue repair in the area of the injury
199
do some chemical messengers provide the sensation of pain? why?
some of these chemical messengers also provide the sensation of pain; pain gets your attention to encourage behavior changes to decrease or prevent further damage to the injured area
200
do endothelial cells retract to expose underlying tissues?
in addition endothelial cells retract to expose underlying tissues in the vessel wall as well as becoming "sticky". this combination helps to initiate platelet plug formation and clotting
201
what has to work together to constrict blood flow?
endothelin released by endothelial cells of blood vessels, thromboxane A2 and serotonin ( a vasoconstrictor), released by platelets, work together to cause dramatic vascular spasm to constrict blood flow.
202
what causes platelets to begin sticking aggregating and degranulating in the area of vessel damage?
exposed collagen fibers in the blood vessel wall and underlying tissues cause platelets to begin sticking, aggregating and degranulating in the area of vessel damage
203
when platelets begin sticking aggregating and degranulating what does it initiate?
this initiates a positive feedback cycle until the damaged area is coated and sealed and blood loss is contained
204
the positive feed back cycle in blood clotting leads to the conversion of what?
these steps also lead to conversion of soluble protein fibrinogen present in plasma, to the insoluble fibrin
205
do the fibers and platelets and cells seal the vessel wall?
these fibers trap more platelets and cells as they form a clot that seals the break in the vessel wall. (another name for a clot is a thrombus)
206
what are the pathways of coagulation?
* Extrinsic mechanism
| * Intrinsic mechanism
207
what is the extrinsic mechanism?
clotting factors released by the damaged blood vessel and perivascular (situated or occurring around a blood vessel) tissues
Damaged perivascular tissues
leads to
thromboplastin (factor III)
208
does the intrinsic mechanism use clotting factors just in its blood?
uses clotting factors found in the blood itself
Platelets
lead to
factor XII
209
do extrinsic and intrinsic mechanisms usually work together?
in most cases of bleeding both extrinsic and intrinsic mechanisms work simultaneously to contribute to hemostasis
210
do bother extrinsic and intrinsic pathways give rise to the activation of Factor X?
extrinsic and intrinsic mechanisms both give rise to the activation of Factor X
211
what are the pathways of coagulation?
a series of enzymatic reactions
212
how many clotting proteins are there? are any skipped?
the 11 proteins involved in coagulation are numbered from 1 to 13 skipping 4&6
213
are most clotting proteins present in the blood and made in the liver?
with the exception of tissue factor (factor III) these proteins and Ca++ are present in the blood (made by the liver)or are formed form other clotting factors in the blood during the coagulation process
214
where are platelet factors 1-4 released from?
platelet factors 1-4 are released form platelets
215
is the final pathway initiated regardless of the initial process?
regardless of how the coagulation starts bother pathways can activate the final common pathway
216
what does the final common pathway cause the formation of?
the final common pathway causes formation of fibrin fibers to mesh with the platelets forming the clot
217
is calcium critical to both extrinsic and intrinsic pathways?
calcium is critical to both the extrinsic and intrinsic pathways
218
does tissue factor released initiate the extrinsic pathway
tissue factor released by damaged endothelial cells or tissue initiates the extrinsic pathway
219
what is the intrinsic pathway initiated by? what causes this to occur?
the intrinsic pathway is triggered by activation of factor XII (hageman factor
this occurs when this protein is exposed to collagen fibers from damaged tissue plus platelet factor (PF-3) from aggregating platelets
220
what are LS capillaries?
lymphatic capillaries are blind-ended tubes with flaps on the ends that are stuck between the capillaries
221
what is the pressure that opens the one way flap type valves in the LS capillaries
it is hydrostatic pressure from interstitial fluid that will open these valves to get flow into the lymphatic capillaries
222
where do the thoracic duct and cysterna chyli (sisterna kiilii) collect lymph from?
the thoracic duct and cysterna chyli collect lymph form the lower part of the body and the left half of the upper body
223
the right lymphatic duct collects lymph from where?
the right lymphatic duct collects lymph from the right upper part of the body
224
the thoracic duct drains into what, before it joins the jugular to form the brachioceplatic vein?
the thoracic duct drains into the left subclavian vein just before it joins the jugular to form the brachiocephalic vein
225
where does the right lymphatic duct drain?
the right lymphatic duct similarly drains into the right subclavian vein near where it joins the jugular
226
how much lymphatic collection does the thoracic and right duct handle?
the thoracic duct handles lymphatic collection from 3/4 of the body while the right duct handles drainage only from the right 1/4
227
does innate immunity require exposure
no
228
what are some mechanisms of components of the immune sysem that fall under innate immunity?
* NK cells
* acid (skin, stomach)
* Macrophages in respiratory and digestive tracts
* granulocytes
* complement system
* inflammation
* fever
229
does adaptive immunity require exposure? if yes does this exposure help to develop anything?
yes,
* antibodies (humoral)
* cytotoxic T cells (cell mediated)
230
is innate immunity nonspecific immunity?
innate immunity is sometimes called nonspecific immunity
231
is adaptive immunity specific or acquired?
adaptive immunity is specific or acquired immunity
232
do innate immunities help to stimulate adaptive immunities?
innate immunity mechanisms help to stimulate adaptive immunity and vice versa
233
do adaptive and innate immunities work together?
yes these two parts of immunity work together to help prevent and kill infection
234
what does the blood group equal?
a blood group =s a locus (gene location DNA)
235
how many alleles can you have at a location in any one person?
you can only have 2 alleles (versions of a gene) at that location in any one person.
236
how many alleles do the ABO blood group have?
the ABO blood group there are 3 possible alleles, A, B, and O
237
how do the cells of the immune system communicate with each other and other cells in the body?
the cells of the immune system communicate with other cells in your body as well as each other with a multitude of cell surface proteins and chemical messengers (cytokines)
238
what do the surface proteins and cytokines help to turn on and off?
the surface proteins and cytokines help to stimulate (turn on) and inhibit (turn off) the destructive activity of certain types of lymphocytes and of the phagocytic cells
239
do cytokines also help to regulate immune responses?
cytokines also help to regulate immune response within immune system cells such as lymphocytes and phagocytic cells but also within cells in most tissues within the body
240
what are the three types of cells in the immune system?
lymphocytes
phagocytic cells
basophils and mast cells
241
what are the cells in the lymphocyte category?
T cells
B cells
NK cells
242
what are the cells in the phagocytic category?
microphages
macrophages
dendritic cells
243
what do T cells do?
T cells: coordination and cell mediated immunity
244
what are the two types of T cells and what do they do?
Helper T cells (CD4)-stimulates and coordinates activity of other T and B cells
Cytotoxic T cells (CD8)- kill specific foreign cells infected cells and cancerous cells
245
what do B cells do?
humoral immunity (adaptive immunity)
246
what are the 3 types of B cells and what do they do?
undifferentiated B cell
plasma cells-make antibodies
memory cell-gives long term immunity
247
what do NK cells do?
NK cells attack foreign cells, infected cells cancerous cells (nonspecific)
248
what are T cells dependent on?
T cells are dependent on the thymus and its hormones for their maturation and differentiation
249
what are B cells dependent on?
B cells are dependent on the bone for their maturation and differentiation
250
are both T and B cells originally formed in red bone marrow
both cells are originally formed in red bone marrow
251
how are lymphocytes identified?
lymphocytes are identified based on the proteins they have on their cell membranes
252
why are T cells and cytotoxic T cells called something different now?
helper T cells are now called CD4 cells and cytotoxic T cells are now called CD8 cells because these proteins are crucial to their functions
253
what were regulatory T cells
regulatory T cells used to be called suppressor T cells
254
did cytotoxic T cells used to be called killer T cells
cytotoxic T cell used to be called killer T cells. cytotoxic T cells require co-stimulation by helper T cells; NK does not
255
do B cells require co-stimulation by helper T cells?
B cells also require co-stimulation by helper T cells
256
is a natural Killer T cell different form a natural killer cell?
there is another type of T cell called a natural killer T cell. this is distinct form a natural killer cell
-the Natural killer T cell expresses some of the protein markers of a NK cell and some of the proteins of a T cell
257
do NK T cells and NK cells produce large amounts of a particular cytokine?
yes these cells are able to produce large quantities of particular cytokines
258
what are NK cells also know as?
they are also know as large granular lymphocytes
259
how do NK cells and cytotoxic T cells kill cells?
NK cells and Cytotoxic T cells are able to kill cells by triggering apoptosis (programmed cell death)
260
are cytotoxic T cells responsible for mediated cell immunity?
yes CT cells are responsible for cell mediated immunity
261
what are B cells responsible for?
b cells and plasma cells are responsible for anibody mediated or humoral immunity
262
can T cells CD$ and CD* and B cells be naïve activated and memory
they can be naïve meaning they have not been exposed to an antigen they recognize yet
they can be activated meaning they have been exposed recently and are currently actively trying to kill the antigen
they can be memory, meaning they were exposed to the antigen in the past and can become activated again quickly if exposed again.
