Week 1: Monday Flashcards
What is the primary role of the CVS?
transport
What are the two modes of transportation
- diffusion
- bulk flow
what is diffusion
- slow over short distances
- passive
- primary mechanism for which dissolved substances move across vessel walls
capillaries
what is bulk flow
- rapid flow over long distances
- requires energy
what are the 5 components of the CVS and their functions
- heart - the pump
- vasculature - transport
- lymphatics - maintain fluid homeostasis
- blood - carries nutrients, gases, hormones, antibodies, and waste
- associated organs - spleen, kidney, bone marrow, liver
what are thoracic sacs
- thorax is compartmentalized by membranes
- distinct functions for the function of heart and lungs
- two plural sacs (around lungs) with different regions
- sac surrounding the heart
what are the 4 different regions of the plural sacs
- costal parietal pleura
- diaphragmatic parietal pleura
- mediastinal parietal pleura
- visceral pleura
where is the heart located
within themediastinum of the thorax
what are the functions of the pericardium
- protect the heart against friction during beating
- anchor the heart
- act as a barrier against the spread of disease
what is the function of the heart
- pump blood
- keep oxygenated and deoxygenated blood separated
- respond to altered physiological demands
why does the left ventricular wall thicker than the right
it needs to pump blood into aorta which pumps blood to entire body
heart valves are responsible for ____ blood flow
unidirectional
what are the 2 atrioventricular (AV) valves and what do they contain
- tricuspid and mitral valves
- papillary muscles and chordae tendineae
what is the function of chordae tendineae
to prevent valve from opening backward during systolic contraction
what are the 2 semilunar valves and what do they lack
- aortic and pulmonic
- lack chordae tendineae
what does the intervenous tubercle do
directs blood from the venae cavae ventrally towards the atrioventricular ostium
what does the trabeculae carneae do
reduce turbulence in the ventricles
what is the cardiac skeleton
- encircles valve openings and separates atria from ventricles
- serves as an attachment site for valves and cardiac muscle
- the trigone can ossify
- act as electrical insulator
electrical activoty in cardiac muscle is ____
myogenic
what does myogenic mean
can spontaneously depolarize on its own
where are action potentials in the heart initiated
sinoatrial node (SA node)
what does the travecula septomarginalis (moderator band) do
provides a shortcut in the conducting pathways
what does nutritional blood supply do
nourishes the organ so it can function
what are the nutritional blood supplies of the heart, lungs, and liver
- heart: coronary arteries
- lungs: bronchial arteries
- liver: hepatic artery
what is functional blood supply
involved with organs function
what are the function blood supplies of the heart, lungs, and liver
- heart: venae caveae and pulmonary veins
- lungs: pulmonic arteries
- liver: portal vein
what is the coronary circulation
- coronary arteries feed the heart
- differences in the coronary patterns across (and within) species
what does the vasculature serve to do
- transport substances throughout body
- help regulate blood pressure
- direct blood to areas where its needed most
- aid in homeostasis (temp, water balance)
the CVS is a ____ system
closed
what is the pulmonic circuit
- all vessels within the lungs
- vessles connecting lungs with heart
- blood flows in series
what is the systemic circuit
- the vasculature throughout the rest of body
- blood flows in parallel
- venous side (volume reservoir)
- arterial side (pressure reservoir)
what supplies blood to the large vessels
vasa vasorum
what is countercurrent exchange
temp conservation, solute balance, local hormone signaling
what is cavernous tissue
found in erectile tissue
what are portal systems
blood flows from one capillary bed straight to another without first returning to the heart/pulmonary circuit
what are vascular anastomoses
- arterio-arterial anastomosis
- veno-venous anastomosus
- arterio-venous anastomosis
connection between to vesses - like a bypass
in postnatal mammals what to arteries do
blood away from heart, oxygenated (systemic circuit)
in postnatal mammals what do veins do
bring blood toward the heart, deoxygenated (systemic circuit)
describe circulation in the fetus
- oxygenated blood enters the fetus from the placenta via the umbilical vein
- deoxygenated blood moves to the placenta via the umbilical arteries
what is the ductus venosus in the fetus
- blood bypasses the liver
- becomes the ligamentum venosum in adults
what is the ductus arteriosus in the fetus
- blood bypasses the lungs
- becomes the ligament arteriosum in adults
what is the foramen ovale in the fetus
- blood bypasses the lungs
- becomes the fossa ovalis in adults
what do the umbilical arteries do in the fetus
- return blood to placenta
- becomes the round ligament of the bladder in adults
what do umbilical veins do in the fetus
- brings blood from the placenta
- becomes the round ligament of the liver in adults
what is blood
- connective tissue
- medium for transport
- helps maintain homeostasis
what is blood composed of
- platelets
- cells (erythrocytes - RBC)
what is the lifecycle of a RBC
- made in bone marrow & triggered to be made by erythropoitetin thats released by kidneys
- kidneys produce EPO that riggers bone marrow to make RBC
- bone marrow releases reticulocytes into bloodstream - mature into erythrocytes that circulate for 120 days
- old and dammaged erythrocytes are phagocytized by macrophages in bone marrow, liver, and spleen
- globin of hemoglobin is metabolized into amino acids and reused in protein synthesis
- heme portion broken down into biliverdin for transport in blood
how to evaluate RBC in blood
- clinicians evalutate froma kinetic and morphological approach:
- concentration/amount
- size
- color
what are some RBC measurements and indices
- RBC count (cells/L or uL)
- hematocrit/packed cell volume (% of RBC in whole blood)
- blood hemoglobin concentration (g/dL)
- mean corpuscular volume (fL or um^3)
- mean corpuscular hemoglobin (pg/cell)
- mean corpuscular hemoglobin concentration (g/dL)
what are the 3 causes of anemia
- inappropriate removal/destruction of RBC
- inappropriate production of RBC
- excessive blood loss
what are the two types of anemia
- regenerative
- non-regenerative
