Exam 2-Cardiovascular System Flashcards
What is cardiac output?
Volume of blood pumped by the heart in one minute.
Cardiac output can be found by multiplying heart rate by the stroke volume; an increase in stroke volume or an increase in heart rate will increase the cardiac output and vice versa.
The rate at which blood is returned to the atria from the vein in one minute is considered ________ return?
Venous
This rate can limit cardiac output.
What is stroke volume?
The volume of blood pumped out of each ventricle with each contraction
The period of cardiac contraction and emptying is the _______ period?
Systolic
Systolic pressure is the measure of what?
The pressure in the artery after blood has been ejected from the left ventricle; this is the highest arterial pressure measurement during the whole cardiac cycle.
What is the period called when the heart relaxes and feel back up with blood?
Diastolic
_______ pressure measures the pressure on the artery when no blood is being ejected from the left ventricle; when the lowest arterial pressure is being measured during the cardiac cycle.
Diastolic
What is pulse pressure?
The difference between the systolic and diastolic pressure
The end _______ volume is the volume in the ventricle before ejection; when the heart is ready to contract.
Diastolic (preload volume)
What is the end systolic volume measuring?
The volume in the ventricle after ejection
What is the equation for the MAP or mean arterial pressure? What is this measuring?
Diastolic pressure+ 1/3( Systolic pressure-Diastolic pressure); The average pressure responsible for driving blood forward into the tissues throughout the cardiac cycle.
What are the three characteristics of blood?
- Viscosity: thicker than water because RBCs
- Temperature: higher than than body temp.
- Slightly alkaline: contains less CO2
The three functions of blood in the body are ______, _______ and __________.
Protection, transportation, and regulation
What must be present in order for the liver to synthesize the clotting factors II, VII, IX, X?
Vitamin K
What is happening to the ventricles during the ST segment?
They are depolarizing, contracting and emptying
What phase of the action potention propagation does the ST segment correspond with?
Phase two: The plateau phase of the action potential in ventricular muscle cells
During the PR segment what is happening to the AV node?
The AV node is delayed in its induction
Why is the AV node’s conduction delayed?
In order to let the atria empty the blood into the ventricle before the ventricle contracts
What part on an ECG represents the area form the end of the P wave to the begining of the QRS complex?
The PR segment
What is the period on the ECG called that begins at the end of the S wave and ends in the begining of the T wave?
The ST segment
How do you calculate the HR using a rhythm strip?
Count the # of QRS complexes between the 3 second markers and multiply by 20
or
Count the # of QRS complexes between the first and third markers (6 seconds) and multiply that number by 10 (more accurate)
True or False: An erythrocyte has an endoplasmic reticulum and a nucleus
False; an erythrocyte is a fully mature red blood cell which loses those structures
What type of cell derives from hemocytoblast and commits to becoming a red blood cell?
Myeloid stem cell
What are erythroblasts called that lose their nucleus?
Reticulocytes
If the length occupied by plasma is 42mm and the length occupied by red blood cells is 38mm, what is the hematocrit value?
42 + 38 = 80
38/80 = 48%
What is the process call when red blood cells are created and are mature?
Erythropoesis