Ch 7- Cardiovascular Flashcards
2 Types of circulation
Pulmonary and Systemic Circulation
Pathway of electrical heart conduction is
SA node, Av node, bundle of his (AV bundle), and purkinje fibers
What is the atrial kick
5-30% of the cardia output that pushes more blood into the ventricles.
Signal is delayed at the AV node why
To allow the ventricles to fill completely
“The muscle cells are connected by _______ which contain many gap junctions directly connecting the cytoplasm of adjacent cells, thereby allowing for coordinated ventricular contraction.”
Intercalated Disks
“Cardiac muscle has myogenic activity, meaning that
it can contract without any neural input.”
“The neural input to the heart is important in speeding up and slowing the rate of contraction, but not generating it in the first place.”
“During _______, the heart is relaxed, the semilunar valves are closed, and blood from the atria fills the ventricles”
Excerpt From: Kaplan. “Kaplan MCAT Biology Review: Created for MCAT 2015 (Kaplan Test Prep).” iBooks.
Diastole
“During _______, ventricular contraction and closure of the AV valves occurs and blood is pumped out of the ventricles.”
Systole
What is Cardiac Output
“total blood volume pumped by a ventricle in a minute”
“Cardiac output (CO) is the product of heart rate (HR, beats per minute) and stroke volume (SV, volume of blood pumped per beat):
CO = HR × SV”
What is the equation for cardiac output?
“Cardiac output (CO) is the product of heart rate (HR, beats per minute) and stroke volume (SV, volume of blood pumped per beat):
CO = HR × SV”
“For humans, cardiac output is about _____ per minute”
5 Liters
“All blood vessels are lined with ______
Endothelial cells
3 Functions of endothelial cells
- Release chemicals that aid in vasodilation-vasoconstriction
- Allow wax to pass through vessel wall
- Release chemicals when damaged for clot formation
Arteries move blood
Away from heart
Only arteries that contain deoxy blood
Pulmonary arteries and umbilical arteries
“there are ______ portal systems in the body, in which blood will pass through two capillary beds in series before returning to the heart.”
What are they?
3
Hepatic portal system, Hypophyseal portal system, Renal Portal System
How does oxygen bind to RBC?
Each erythrocyte contains about 250 million molecules of hemoglobin, each of which can bind four molecules of oxygen. Therefore, each red blood cell can carry approximately 1 billion molecules of oxygen.”
“Oxygen does not simply dissolve in the cytoplasm of the red blood cell—remember, molecular oxygen is nonpolar and therefore has low solubility in aqueous environments. ”
Why are RBC biconcave?
- allows to trade thru tiny capillaries
2. Increases surface area, allows greater gas exchange
“Red blood cells are also unique in that, when they mature, the nuclei, mitochondria, and other membrane-bound organelles are
Lost
Since no mitochondria doesn’t carry out oxidative phosphoralization. Rely on glycolysis for atp and lactic acid fermination.
RBC have no nuclei so they are unable to
Divide
Live for 120 days
“Hemoglobin measures
the quantity of hemoglobin in the blood, giving a result in grams per deciliter.”
“is a measurement of how much of the blood sample consists of red blood cells, given as a percentage. ”
Hematocrit
2 types of leukocytes
Granulocytes, Agranulocytes
2 types of agranulocytes
Lymphocytes and monocytes