Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
183 Cards in this Set
- Front
- Back
|
Burkinge fibers go to which walls?
|
Apex and the ventricular walls.
|
|
|
How many times per minute do Burkinge fibers fire without input from AV node?
|
30 times per minute.
|
|
|
Mechanical events of the cardiac cycle.
|
All events of blood flow through heart in one complete heartbeat.
|
|
|
Systole is what?
|
Contraction.
|
|
|
Diastole is what?
|
Relaxation
|
|
|
What are the phases of the cardiac cycle?
|
Ventricular filling, Ventricular systole, isovolumetric relaxation.
|
|
|
What is ventricular filling?
|
Mid-late diastole, AV valves open, 80% of blood passively flows into ventricles. Atrial Systole is the next 20%.
|
|
|
Ventricular Systole?
|
Atria relax, ventricals begin to contract rising ventricular pressure equals closing of AV valves. Isovolumetric contraction phase= all valves close. Ejection phase= ventricular pressure exceeds pressure in large arteries and forces the SL valves open.
|
|
|
Isovolumetric relaxtion occurs when?
|
Early Diastole.
|
|
|
What is isovolumetric relaxation?
|
Backflow of blood in aorta and pulmonary trunk closes the SL valves and causes the dicrotic notch(brief rise in aortic pressure)
|
|
|
Cardio Output(CO)
|
Volume of blood pumped by each ventricle in one minute.
|
|
|
How do you calculate CO?
|
CO=heart rate x stroke volume. Look in book how to figure out the rest, do it now!!!
|
|
|
Homestatic imbalances?
|
Tachycardia=abnormally fast heart rate, x>100bpm.
Bradicardia=slow heart rate. x<60 bpm. |
|
|
If tachycardia is present it can lead to?
|
Fribulation.
|
|
|
Bradicardia if persistant may result in?
|
Inadequate blood circulation.
|
|
|
What are the embryonic heart chambers?
|
Sinus eneous.
Atrium. Ventricle. Bulbous cortis. |
|
|
What is foramen ovale?
|
Connects the two atria in fetal heart structures.
|
|
|
What is the ductus arteriosus?
|
Connects the pulmonary trunk and the aorta in fetal heart structures.
|
|
|
Three types of blood vessels?
|
Arteries
Veins Cappilaries |
|
|
What are arteries?
|
Blood flow away from the heart, containing oxygen except pulmonary circulation and umbillical vessels of fetus.
|
|
|
What are cappilaries?
|
Contact tissue cells
|
|
|
What are veins?
|
Structures that carry blood towards the heart.
|
|
|
What are the 3 layers of arteries and veins?
|
Tunica intima
Tunica media Tunica externa |
|
|
What is the structure of the lumen?
|
Central blood containing space.
|
|
|
What is the structure of capillaries?
|
Endothelium with sparse basal lamina.
|
|
|
Define Elastic arteries?
|
Conducting arteries are large thick walled with elastin in all 3 tunics.
|
|
|
Give an example of an elastic artery.
|
The aorta and it's major branches.
|
|
|
What does a large lumen in an elastic artery give rise to?
|
Low resistance to blood flow, and also acts as a pressure reservoir as blood is ejected from the heart.
|
|
|
Describe muscular arteries and arterioles.
|
Distal to the elastic arteries and deliver blood to the body.
Have a thick tunica media and more smooth muscle. Active in vasoconstriction, or bringing the blood to the center of the body. |
|
|
Desribe arterioles.
|
Smallest arteries, lead to capillary beds, and control flow into capillary via vasodialation or vasoconstriction.
|
|
|
What are the 3 structural types of capilarries?
|
Continuous capillaries
Fenestrated capillaries Sinusoidal capillaries(aka sinusoids) |
|
|
What are capillaries?
|
Microscopic blood vessels.
|
|
|
Where are capillaries present in the body?
|
In all tissues except:
Cartilage Epithelia Cornea, and the lens of eye |
|
|
What are pericytes?
|
They help to stabilize the walls and control permeability of the capillaries.
|
|
|
What does capillary size affect?
|
Passage of only a single red blood cell at a time.
|
|
|
What are the two types of vessels in capillary beds?
|
Vascular shunt
True capillaries |
|
|
Describe a Vascular Shunt.
|
Metarteriole - thoroughfare channel
Directly connects terminal arteriole and post capillary venule. |
|
|
Describe true capillaries.
|
10-100 exchange vessels per bed.
Branchg off metarteriole or terminal arteriole. |
|
|
What regulates blood flow into true capillaries?
|
Precapillary sphincters regulate flow. Which is controlled by local chemical conditions and vasomotor nerves.
|
|
|
How are venules formed?
|
When capillary beds unite.
|
|
|
Venules contain?
|
1-2 layers of muscle cells
|
|
|
Structure of veins
|
Thinner walls
Larger lumens compared to arteries. |
|
|
Vein BP is what compared to arteries? Higher or lower?
|
Lower
|
|
|
Vein structure
|
Thin tunica media and thick tunica sterna consisting of collagen fibers and elastic networks
|
|
|
Capacitance vessels
|
Blood reservoirs, contain up to 65% of the blood supply
|
|
|
Adaptations ensure 1 way flow of blood how?
|
Large diameter lumens - little resistance
Valves prevent backflow |
|
|
Venous sinuses are?
|
Flattened veins with very thin walls
Example: Coronary sinus of heart and dural sinus of brain |
|
|
Vascular anastomoses are?
|
Interconnectino of blood vessels.
|
|
|
Arterial anastomoses are?
|
Alternate pathways common in joints, abdominal organs, brain, and heart.
|
|
|
Aterovenous anastomoses would be?
|
Vascular shunts of capillaries.
|
|
|
Blood flow defined is.
|
volume flowing through a vessel organ or entire circulation in a given period.
|
|
|
Blood flow is measured as?
|
ML / min
|
|
|
Blood flow is equal to what in your body?
|
Cardiac output for entire vascular system
|
|
|
Blood pressure is?
|
Force per unit area exrted on wall of a blood vessel by blood
|
|
|
Blood pressure is expressed as?
|
mm Hg
|
|
|
What keeps blood flowing?
|
Pressure gradient of blood.
|
|
|
What is the amount of friction that blood encounters?
|
Peripheal resistance.
|
|
|
What are the 3 important sources of blood resistance?
|
blood viscosity
total blood vessel length blood vessel diameter |
|
|
How is blood pressure controlled short term?
|
Neural and hormonal controls by counteracting fluctuations in BP by altering peripheral resistance.
|
|
|
How is blood pressure controlled long term?
|
Blood volume change.
|
|
|
What is the vasomotor center?
|
Sympathetic neurons that cluster in the medulla, oversee changes in vessel diameter.
|
|
|
Where does the vasomotor center recieve input from to control BP?
|
Baroreceptors, chemoreceptors and higher brain centers.
|
|
|
Where are baroreceptors located at?
|
Carotid sinuses
Aortic arch Walls of larger arteries of the neck and thorax |
|
|
Where are chemoreceptors located at?
|
Carotid sinuses
Aortic arch Large arteries of the neck |
|
|
What do chemoreceptors respond to?
|
A rise in C02 or a drop in Ph, or 02.
|
|
|
Which hormones does the medulla secrete to control BP?
|
norepinephrine, and epinephrine cause generalized vasoconstriction and increased cardiac output.
|
|
|
Where is Agiotensin II released from?
|
Generated by kidney release of renin, and causes vasoconstriction.
|
|
|
Which receptors adapt quickly to chronic high or low BP?
|
Caroreceptors
|
|
|
What are the renal mechanisms?
|
Indirect and Direct
|
|
|
How do direct renal mechanisms control BP?
|
angiotensisn works by lowering arterial BP and stimulates ADH through a chain of events.
|
|
|
How do the indirect renal mechanisms control BP?
|
Alters blood volume independently of hormones.
|
|
|
How do you monitor circulatory efficiency?
|
Vital signs
|
|
|
What are vital signs?
|
Pulse
Blood pressure Respiratory rate Body temperature |
|
|
What are alterations in BP?
|
Hypertension and hypotensions?
|
|
|
What are signs of hypotension?
|
Systole less then 100 mm Hg
|
|
|
What is hypotension often linked with?
|
Long life and lack of cardiovascular illness, in other words being healthy.
|
|
|
What is hypertension?
|
High blood pressure
|
|
|
What are the signs of hypertension?
|
Read in the book!
|
|
|
What is blood flow through body tissues?
|
Tissue perfusion
|
|
|
Describe tissue perfusion and it's benefits
|
Delivery of 02 nutrients, removes wastes
Gas exchange(lungs) Absorption of nutrients(digestive tract) Urine formation(kidneys) |
|
|
If tissue perfusion is correct, what is the result?
|
Proper body function
|
|
|
What is autoregulation?
|
The automatic adjustment of flow to each tissue as needed in the body.
|
|
|
How is autoregulation controlled in the arterioles?
|
Modifying the diameter of local arterioles
|
|
|
What are the two types of autoregulation?
|
Metabolic
Myogenic |
|
|
What are the metabolic controls of blood flow in tissues?
|
Vasodialation of arterioles and relaxation of precapillary sphincters.
|
|
|
What does the vasodialation of arterioles and relaxation of precapillary sphincters does what?
|
Results in declining tissue 02.
|
|
|
What are the effects of the metabolic controls to tissue pefusion?
|
Relaxation of vascular smooth muscle
Release of NO from vascular endothelial cells |
|
|
What is a major chemical factor in vasodialation?
|
Nitrous Oxide
|
|
|
What is vasoconstriction?
|
sympathetic stimulation and endothelins
|
|
|
What do the myogenic controls do with tissue perfusion?
|
Keep perfusion constant despite most fluctuation in sympathetic pressure due to vascular smooth muscles
|
|
|
What does the passive stretch in arteries do?
|
increased intravascular pressure
which equals increased tone and vasoconstriction |
|
|
What do reduced stretch in arteries promote?
|
Vasodialation - increasing blood flow to tissues
|
|
|
What are the long term autoregulation method of tissue perfusion?
|
Angiogenesis
Increased number of blood vessels and existing vessels become enlarged. |
|
|
Where is angiogenesis commoin in the body?
|
Heart and thru out the body in high altitude areas.
|
|
|
The blood flow in the brain is what kind of flow?
|
A constant flow.
|
|
|
What do neurons hate when it comes to blood supply?
|
They hate ischemia, or a restricted blood supply.
|
|
|
MAP equals what?
|
Mean Arterial Pressure
|
|
|
The myogenic controls of BP in the brain react to what?
|
MAP
|
|
|
As MAP decreases, cerebral vessels do what in the brain?
|
Dilate for more blood flow.
|
|
|
As MAP increases, cerebral vessels do what in the brain?
|
Constrict, to keep pressure constant.
|
|
|
At what number for MAP does fainting happen?
|
Under 60 mm Hg
|
|
|
Where is the venous plexus?
|
Under the skin surface.
|
|
|
Blood flow through the skin does what?
|
Supplies nutrients to cells
Helps maintain body temperature Provides a blood reservoir |
|
|
Blood flow to the venous plexuses is how much?
|
50-2500 ml/min depending on body temp
|
|
|
What is special with the autoregulation of blood flow in the lungs?
|
It's opposite of most tissues, low 02 = vasodialation.
|
|
|
What happens with the blood flow through the heart?
|
Coronary vessel compress
Myocardial blood flow ceases Stored myoglobin supplies 02 |
|
|
How is the blood flow through the heart controlled when at rest?
|
Most likely myogenic
|
|
|
What is vasomotion through capillaries?
|
slow and intermittent flow
reflects opening and closing of precapillary sphincters |
|
|
What diffuses during cappillary exchange of respiratory gases and nutrients?
|
02 and nutrients
C02 and metabolic wastes |
|
|
Lipid soluble nutrients diffuse how through capillary walls?
|
Directly through.
|
|
|
Water soluble nutrients diffuse how through capillary walls?
|
They pass through holes.
|
|
|
Larger molecules diffuse how through capillary walls?
|
They are actively transported.
|
|
|
What do fluid movements in bulk flow do?
|
Determine relative fluid volumes in blood and interstitial space
|
|
|
The direction and amount of fluid flow depends on what 2 opposing forces?
|
Hydrostatic
Collid osmotic pressure |
|
|
What is hydrostatic pressure mean?
|
Capillary blood pressure.
|
|
|
What is collod osmotic pressure mean?
|
Concentration gradient.
|
|
|
what is blood
|
fluid connective tissure
|
|
|
what is blood composed of?
|
plasma and formed elements
|
|
|
what are formed elements?
|
erythrocytes, leukocytes, and platelets
|
|
|
what are erythrocytes
|
red blood cells
|
|
|
what are leukocytes?
|
white blood cells
|
|
|
What is hematocrit?
|
% of blood that is RBCs
|
|
|
what % of blood is composed of hematocrit?
|
47% +/- 5% for males
42% +/- 5% for females |
|
|
what percent of the blood is composed of plasma?
|
55% of whole blood
|
|
|
From least to most dense list the blood components.
|
Plasma = least dense
Buffy Coat = middle Erythrocytes = most dense |
|
|
What percent of the blood is composed of Erythrocytes?
|
45%
|
|
|
How much of a % of the whole blood is the buffy coat?
|
1%
|
|
|
what are the functions of blood?
|
distribution, regulation, & protection
|
|
|
What does blood distribute?
|
Distributes: o2 and nutrients, metabolic waste, and hormone
|
|
|
what does blood regulate & how?
|
body temp by absorption and distribution,normal pH via buffers and fluid volume
|
|
|
What does blood protect & how?
|
bloodloss (via clotting), infection (via antibodies, pomplements proteins & WBCs)
|
|
|
what is blood plasma composed of?
|
water, proteins, nitrogenous waste, nutrients,electrolytes, respritory gasses & hormones
|
|
|
How much of plasma compositon is water?
|
90%
|
|
|
what proteins are found in plasma? & in what percentages?
|
albumin 60%
globulins 36% fibrogen 4% |
|
|
What process produces nitrogenous waste into the blood plasma? and what nitrogenous waste is present in plasma?
|
metabolism
-lacic acid -urea -creatine |
|
|
what nutrients are present in Blood plasma?
|
glucose, carbs, and amino acids
|
|
|
which electrolytes are present in blood plasma?
|
Na+, K+, Ca2+, Cl-, HCO3-
|
|
|
Which respritory gasses are present in Blood plasma?
|
O2 & CO2
|
|
|
What are formed elements?
|
WBCs, RBCs, & Platelets
|
|
|
How long to most formed elements survive?
|
a few days
|
|
|
where are most formed elements made at?
|
in the bone marrow
|
|
|
What are WBCs?
|
complete cells?
|
|
|
What is different aobut RBCs?
|
They don't have nuclei or organelles.
|
|
|
What are platelets?
|
cell fragments
|
|
|
What is the abbreviation for erythropiotin?
|
EPO
|
|
|
What is tissue hypoxia?
|
Too few red blood cells.
|
|
|
What is the negative side effects of too many RBCs?
|
increased blood viscosity
|
|
|
The balance of RBC destruction and production depends on?
|
Hormonal controls
Adequate supplies of iron, amino acids, and B vitamins. |
|
|
What enhances EPO production?
|
Testosterone
|
|
|
What are the dietary needs for erythropiosis?
|
Nutrient needs include lipids, amino acids, carbs.
Iron and B12. |
|
|
Define erythropiosis.
|
The production of red blood cells.
|
|
|
Where is iron stored at for EPO?
|
Hemoglobin 65%
Liver, spleen, marrow. |
|
|
What are the two different types of iron?
|
Ferretin and hemociderin.
|
|
|
How is iron transported?
|
Loosely, iron is bound to transferin protien.
|
|
|
Why are vitamin B12 and folic acid necessary for DNA synthesis?
|
For cell division.
|
|
|
Where do macrophages engulf dying RBCs?
|
Spleen.
|
|
|
What is globulin metabolized into?
|
Amino acids.
|
|
|
What are the 4 phases of development for RBCs?
|
1. Ribosome synthesis
2. HB accumulation 3. ejectino of the nucleus and formation of reticulocytes 4. Reticulocytes become mature erythrocytes. |
|
|
Your heartbeat's 2 sounds are what? generally speaking
|
sounds of 2 valves closing
|
|
|
What is the first valve that closes in your heartbeat?
|
AV valve closes
|
|
|
What is the second valve closing in your heartbeat?
|
SL valve closes
|
|
|
Which valve closing signals the beginning of diastole?
|
SL valve
|
|
|
Which valve closing in your heart signals the beginning of systole?
|
AV valve
|
|
|
What type of hearbeat happens from a defective SA node?
|
40-60 BPM, and the AV node takes over for the heartbeat.
|
|
|
A defective AV node may result in?
|
Partial or total heart block because few or no impulses from SA node reach the ventricles.
|
|
|
What do the Purkinje fibers basically do?
|
Makes the heart beat evenly.
|
|
|
The right and left bundle branches are found where in the heart?
|
In the 2 pathways in the interventricular septum.
|
|
|
The right and left bundle branches carry impulses towards where in the heart?
|
The apex of the heart.
|
|
|
The atrioventricule bundle is also known as?
|
The bundle of HIS.
|
|
|
What is the only electrical connection between the atria and the ventricles?
|
Atrioventricular bundle.
|
|
|
The SA node constitutes what rhythm in the human body?
|
Sinus rhythm.
|
|
|
What is the pacemaker of the heart?
|
SA node.
|
|
|
How often does the SA node generate impulses?
|
75 times/minute.
|
|
|
What percentage of cardiac cells are automatic?
|
1%
|
|
|
What do gap junctions promote in the heart?
|
That the heart contracts as a unit.
|
|
|
What 3 things trigger a vascular spasm?
|
Direct injury
Chemical releases Pain reflexes |
|
|
What are arterial anastomoses? Where are they most common? 4 spots
|
Alternate pathways that are commin in joints, abdominal organs, brain, and the heart.
|
|
|
What is the common donor blood type?
|
O
|
|
|
What is the common reciever blood type?
|
AB
|
|
|
What are the most numerous WBCs?
|
Neutrophils
|
|
|
Which WBC is the bacteria slayer?
|
Neutrophils
|
|
|
Which WBCs digest parasitc worms that are too large to phagocytized?
|
Eosophils.
|
|
|
What are 2 of the properties of granulocytes?
|
Phagocytic
Lobed nuclei Larger and shorter lived then RBC They stain specifically with the correct stain |
