circulatory system Flashcards
right atrium
low pressure receiving chambers
right ventricle
high pressure discharging chambers
left atrium
low pressure receiving chambers
left ventricle
high pressure discharging chambers
Mitral/bicuspid valve
between left ventricle and left atrium
Tricuspid valve
between right atrium and right ventricle
Pulmonary semilunar valve
between right ventricle and pulmonary artery and allows blood to flow from the heart to the lungs
Aortic semilunar valve
between left ventricle and aorta and carries blood from the heart to the rest of the body
Aorta
sends oxygen-rich blood to the body
Superior/inferior vena cava
sends oxygen poor-blood to the right atrium
Pulmonary circulation loop
send oxygen-poor blood to lungs and return oxygenated blood to pulmonary veins and left atrium
Steps of pulmonary circulation loop
Right ventricle
Pulmonary semilunar valve
Pulmonary trunk
Right and left pulmonary arteries (deoxygenated)
Lungs (capillaries transfer)
Pulmonary veins
Left atrium
Bicuspid/mitral valve
Left ventricle
Steps of systemic loop
Left ventricle
Aortic semilunar valve
Aorta
Body
Superior/inferior vena cava
Right atrium
Tricuspid valve
Right ventricle
systemic loop
send oxygen-rich blood to body and return unoxygenated blood to superior/inferior vena cava
systolic pressure
Systolic BP is the first number in measuring BP; peak pressure produced by contraction ventricles/relaxed atria; Lub sound of bicuspid and tricuspid valves closing
diastolic pressure
Diastolic BP is the second number in measuring BP; minimum pressure in arteries when ventricles are relaxed/contracting atria; Dub sound of the pulmonary semilunar valve and aortic semilunar valve closing
increased viscosity has what affects on BP and blood flow
increased resistance, decreased blood flow
Increased vessel length has what affects on BP and blood flow
increased resistance, decreased blood flow
Decreased vessel diameter has what affects on BP and blood flow
increased resistance, decreased blood flow
Relationship between blood flow and resistance
When blood flow increases, resistance decreases
How does the body respond to short term changes in blood pressure
The brain alters the distribution of blood flow around the body by changing the diameter of certain blood vessels
BP stretches the arterial walls and mechanically gated sodium channels open
Increased BP=increased action potentials to the brain, which dilates arterioles and reduces heart rate
why is high blood pressure detrimental to overall health?
Increased blood flow or resistance is bad for the heart because it produces more muscle around the left ventricle, which needs oxygen;
there is not enough blood, therefore there is not enough oxygen
Diuretics
lower the blood pressure by inducing sodium and fluid loss
Beta-blockers
block the effects of the hormone epinephrine, also known as adrenaline, causing the heart to beat more slowly and with less force, which lowers blood pressure.
ACE inhibitors
reduce blood pressure by relaxing your blood vessels
Calcium channel blockers
lower blood pressure by allowing blood vessels to relax and open
arteries
carry oxygen-rich blood away from the heart and to the body
veins
carry oxygen-poor blood back to heart to pump to the lungs
capilaries
transport blood, nutrients and oxygen to cells in your organs and body systems and connect arteries and veins
arterioles
mini arteries that branch into capillaries
venules
mini veins that suck blood out of the capillaries
layers of blood vessels
Tunica intima
Tunica media
Tunica externa
tunica intima
simple squamous epithelial tissue, connective tissue, and internal elastic membrane; allow fluid to flow smoothly and are interspersed with valves that ensure the flow continues in one direction
Tunica media
smooth muscle cells and elastin; provides support for the vessel and changes vessel diameter to regulate blood flow and blood pressure.
Tunica externa
loosely woven collagen fibers that protects and reinforces the blood vessel; controls vasoconstriction and vasodilation
vasoconstriction
the narrowing of blood vessels
vasodilation
the widening of blood vessels
capillary beds
interwoven network of capillaries that delivers oxygen and nutrients in blood to destinations via diffusion
how heat, cold, and activity affect the function of capillary beds?
When they tighten, blood bypasses some capillaries,
meaning less blood is exposed to the cold and you lose less heat;
when we get hot, blood vessels leading to the skin capillaries dilate, allowing more blood to flow through the skin and more heat to be lost
How do pressure gradients move fluid and gasses within the capillary beds?
The cells send their CO2 to the venal end of the capillary exchange where the capillaries unite into venules and then merge into veins that head back to the heart
Pressure in these vessels drops since fluids always flow from higher to lower pressure
Since the pressure is so low in your veins there isn’t much pressure gradient left to push the blood back to your heart, so veins require some extra venous valves that help keep the blood from flowing backward.
how would a blood cell circulate from the heart to a capillary bed and back to the heart again?
Right ventricle
Pulmonary semilunar valve
Pulmonary trunk
Right and left pulmonary arteries (deoxygenated)
Lungs (capillaris transfer)
Pulmonary veins
Thumb Capillary Bed
Radial vein
Brachial vein
Subclavian vein
Superior vena cava
Right atria
Right ventricle
Lungs
Left atria
Left ventricle
Aorta
bulk flow
Movement of large numbers of molecules across membrane
simple diffusions
Automatic flow from high concentration to low concentration (keep molecules close together)
Breathing in
Diaphragm and external intercostals contract, lifting the ribs up/out and chest cavity expands
Lung pressure is lower than air pressure outside body so the lungs fill with outside air
Breathing out
diaphragm and external intercostals relax, depressing the ribs and chest cavity compresses
Lung pressure is higher than air pressure outside body so the lungs empty the air in lungs
How do blood cells exchange oxygen and CO2 to maintain homeostasis
Bronchioles empty into alveolar ducts, which enter alveolar sacs, where gas exchange occurs
Alveoli are lined with wet simple squamous epithelial tissue
Oxygen dissolves across the epithelial cells, endothelial cells or capillaries and into the bloodstream
Carbon dioxide diffuses out in the alveoli
Partial pressure gradients
In a mixture of gases, if there is an area with a high concentration of a particular gas, it will diffuse to an area of less concentration
how do changes in blood temperature change how hemoglobin binds to gasses in the blood?
Heat and CO2 activate the release of oxygen by lowering hemoglobins need for it
Heat and CO2 change the shape of hemoglobin
how do changes in CO2 concentration change how hemoglobin binds to gasses in the blood?
Spike in CO2 released by active muscle tissues makes blood more acidic
Blood when mixed with CO2 created carbonic acid and breaks down into bicarbonate and hydrogen ions, which change the hemoglobin shape and no longer need O2 (Bohr Effect)
how does the lymphatic system collects, filters, and returns interstitial fluid back to the bloodstream
Lymph passes through lymph nodes, which filter and clean the lymph. Eventually, your body discards the waste and returns the filtered lymph to the bloodstream
how does the lymphatic system fights infection?
Lymphocytes in the lymph node can alert macrophages to attack unwanted microorganisms and activate the immune system outside of the node for support
lymph nodes
Monitor and cleanse lymph
lymphoid organs
Spleen, thymus, adenoids and tonsils;
Thymus and spleen hold lymphocytes, which are maturing immune cells
MALT areas
In mucous membranes around the body and outside lymphatic vessels
right lymphatic duct
drains lymph from upper right torso, arm, head and thorax into the internal jugular vein
larger thoracic duct
drains lymph from rest of the body into subclavian vein
hypertension
Creates high BP and blood vessels have to withstand extra pressure; Over time, the increased force of blood against the arterial walls can make them stiffen, leak, or rupture, while the heart itself may simply wear out from all the extra work it’s doing to keep blood moving
Cerebrovascular accident
Lack of blood and oxygen to the brain
lymphedema
Any blockage in the lymph system that causes swelling and can constrain blood flow
pressure ulcers
Constant pressure on the tissue overpowers the pressure of the capillaries, affecting blood flow
chronic obstructive pulmonary disorder
Damage to the airways and lungs
