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
“Lymphocyte maturation takes place in one of three locations. Those lymphocytes that mature in the spleen or in lymph nodes are referred to as ”
B Cells
-Responsible for antibody generation
Lymphocytes that mature in the thymus are called”
T-Cells
“once monocytes leave the bloodstream and enter an organ, monocytes are renamed”
macrophages
Macrophages of CNS
Microglia
Macrophages of skin
Langerhans cells
Macrophages of bone
Osteoclasts
“The production of blood cells and platelets is called”
Hematopoiesis
Triggered by hormones growth factors and cytokine
“is secreted by the kidney and stimulates mainly red blood cell development”
erythropoietin
“secreted by the liver and kidney and stimulates mainly platelet development”
Thrombopoietin
“Red blood cells express surface proteins called”
Antigens
“any specific target (usually a protein) to which the immune system can react.”
Antigen
“The two major antigen families relevant for blood groups are the”
“ABO antigens and the Rh factor.”
“class of erythrocyte cell-surface proteins, the A and B alleles are”
Codominant
“The O allele (i or O) is ______ to both the A and B alleles. ”
Recessive
“Because the A and B alleles are dominant, the genotypes for A may be”
IAIA or IAi
“(IA and IB are codominant, i is recessive).”
Type O blood people can receive blood from
Only O
An Rh neg individual who has never been exposed to Rh + positive blood has antibodies?
No.
Must be exposed to it first
This is unlike the ABO antigens which we automatically have antibodies for the antigens we don’t have.
“Rh-positivity follows __________ inheritance;
Excerpt From: Kaplan. “Kaplan MCAT Biology Review: Created for MCAT 2015 (Kaplan Test Prep).” iBooks.
Autosomal Dominant inheritance
one positive allele is enough for the protein to be expressed.”
“Capillaries within the body can dilate and constrict to”
Maintain proper body temperature
“The largest drop in blood pressure occurs across the _________.
Arterioles
This is necessary because the capillaries are thin-walled and unable to withstand the pressure of the arterial side of the vasculature.”
Oms law (V=IR) can be translated to pressure difference equation in the circulatory system how
ΔP = CO × TPR
“where ΔP is the pressure differential across the circulation, CO is the cardiac output, and TPR is the total peripheral (vascular) resistance.”
“Resistance is based on three factors:”
Resistivity, Lengh, and crossectional area
“The longer a blood vessel is, the ______ resistance it offers. The larger the cross-sectional area of a blood vessel, the _______ resistance it offers.”
More, less
_________ are specialized neurons that detect changes in the mechanical forces on the walls of the vessel.”
Baroreceptors
“Oxygen is carried primarily by ______ in the blood”
hemoglobin
The binding of oxygen occurs at
the heme groups central iron atom
“The binding or releasing of oxygen to or from the iron atom in the heme group is an
oxidation–reduction reaction.”
“some oxygen does diffuse into the blood and dissolve into the plasma, but this amount is _______ compared to the quantity of oxygen bound to hemoglobin”
negligible
“The level of oxygen in the blood is often measured as the partial pressure of O2 within the blood, or PaO2. A normal PaO2 is approximately ”
70-100mmhg
involves taking blood sample from artery
“percentage of hemoglobin molecules carrying oxygen”
Oxygen saturation
“As the first oxygen binds to a heme group, it induces a conformational shift in the shape of hemoglobin from taut to relaxed. This shift increases hemoglobin’s affinity for oxygen, making it _______ for subsequent molecules of oxygen to bind to the remaining three unoccupied heme groups. ”
Easier
Once all of the hemoglobin subunits are bound to oxygen, the removal of one molecule of oxygen will induce a conformational shift, decreasing the overall affinity for oxygen, and making it easier for the other molecules of oxygen to leave the heme groups.
“This phenomenon is a form of allosteric regulation referred to as cooperative binding and results in the classic sigmoidal (S-shaped) oxyhemoglobin dissociation curve”
“Carbon dioxide can be carried by hemoglobin, but hemoglobin has a much ________ affinity for carbon dioxide than for oxygen.”
Lower
“The vast majority of CO2 exists in the blood as the
bicarbonate ion (HCO−3).”
“Increased carbon dioxide production will cause a _______ in the bicarbonate buffer equation, resulting in decreased pH (increased [H+]).”
Excerpt From: Kaplan. “Kaplan MCAT Biology Review: Created for MCAT 2015 (Kaplan Test Prep).” iBooks.
Right shift
“These protons can bind to hemoglobin, reducing hemoglobin’s affinity for oxygen. This decreased affinity can be seen in the oxyhemoglobin curve as a shift to the right; this is known as the Bohr effect.”
“Causes of a right shift of the oxyhemoglobin curve”
(Decrease 02 affinity of HB) (increased loading into tissues)
Excerpt From: Kaplan. “Kaplan MCAT Biology Review: Created for MCAT 2015 (Kaplan Test Prep).” iBooks.
“Exercise is the right thing to do”
Things that occur during exercise
- Increased PaCO2
- Increased [H+] (decreased pH)
- Increased temperature
- 2,3-bisphosphoglycerate (2,3-BPG), a side product of glycolysis in red blood cells.”
“A left shift, like the blue line in Figure 7.10, may occur due to
decreased PaCO2, decreased [H+], increased pH, decreased temperature, and decreased 2,3-BPG.” Fetal hemoglobin (HbF) Higher affinity
“Fetal hemoglobin has a _____ affinity for oxygen than adult hemoglobin, and therefore has a left-shifted curve compared to adult hemoglobin.”
Higher
Fats are absorbed into in________ the small intestine, bypassing the hepatic portal circulation to enter system circulation via the_______
lacteals, thoracic duct
2 Two types of pressure gradients essential for maintaining proper fluid volume and solute concentrations between blood and the intersititium
Hydrostatic and osmotic (oncotic) pressures
The force per unit area that the blood exerts agains the vessel walls
Hydrostatic Pressure
Can be measured as blood pressure in the large arteries
The Sucking pressure generated by solutes as they attempt to draw water into the bloodstream
Osmotic pressure
most of the osmotic pressure is attributable to plasma proteins and usually called oncotic pressure
At the arteriole end of capillary bed hydrostatic pressure is much _____ than oncotic pressure. When fluid moves out hydrostatic pressure drops but ________ stays the same. So at the venue end of capillary bed _________ is below onconitc pressure and fluid moves _______
Greater, Osmotic pressure, In
_________ pressure pushes fluid out of vessels and is dependent on blood pressure driven by the heard and elastic arteries
Hydrostatic pressure
________ pulls fluid back into the vessels and is dependent on the number of particles dissolved in the plasma.
Osmotic pressure
-Most are proteins so we often refer to this as oncotic pressure
Acummulaiton of excess fluid in the intersitium results in
Edema
interstitial fluid taken up by lymphatic system
Lymphatic fluid (lymph) return to circulatory system by way of the
Thoracic duct
The balance of the opposing pressure of hydrostatic pressure and osmotic pressure is called
Starling forces
Clots are composed of what 2 things
Coagulation factors (protein) and platelets
When endothelium damaged, it exposes undying ct which contains
Collagen and protein called tissue factor
Platelets detect injury and release contents and climb together
Coagulation factors secreted by the _______ sense tissue factor and initiate a complex ________
Liver, Activation cascade
Endpoint of the clotting cascade is
Thromboplastin converts prothrombin to thrombin
Thrombin then converts fibrinogen to fibrin
(fibrin forms small fibers that aggregate into woven structure)
(clot is broken down by plasmin generated from plasminogen)
To break down a clot it is accomplished primarily by ______ which is generated from
Plasmin, Plasminogen
Systole refers to period during ventricular contraction when the _______ valves are close
AV
Diastole is when the heart is relaxed and the _______ valves are closed
Semilunar
Cardiac output is product of what
Heart rate and stroke volume
A _______ system is one in which blood passes through 2 capillary beds in series.
Portal system
Hepatic, hypophyseal, and renal
In the _______ blood travels from gut capillary beds to liver capillary bed via hepatic portal vein
Hepatic portal system
In the _______blood travels from hypothalamus to anterior pituitary
Hypophyseal portal system
In the ___________ blood travels from the glomerulus to the vasa recta through an efferent arteriole
Renal portal system
Postitive Rh factor is _________
Dominant!
Rh- will ONLY create anti Rh ab after exposure to Rh+ blood
