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How does increase venous return increase heart rate?
Increase in Venous returns increases end diastolic volume (EDV). This increase in volume stretch the atrial and ventricular walls. This also stretches the SA nodal fibers and AV nodal fibers triggering a homeostatic response to increase heart rate by up to 15-30% depending on individual and other factors.
What is the right PAV in the coronary arteries of the heart?
''Distal right coronary artery continuation segment (R PAV): The terminal portion of the right coronary artery in a right dominant circulation. This segment lies in or near the atrioventricular (AV) groove and gives rise to a variable number of right posterolateral segments. This segment is the terminal portion of the right coronary artery and begins at the bifurcation of the distal RCA and PDA and gives rise to the AV nodal artery as well.
Where is the nervous tissue located in the heart?
Sympathetic innervation of the heart is from cardiac accelerator nerves descending from the uppermost thoracic sympathetic ganglia and the cervical sympathetic ganglia. Parasympathetic innervation comes from the vagus nerve (Cranial Nerve X). These nerves continue into the walls of the heart and provide autonomic innervation, which can only modify the rate and contractility of the heart. Inside the heart, intrinsic pacemaking comes from the sinoatrial node, which automatically paces the heart due to the existence of "funny currents" (seriously, that's what they're called) that depolarize the node. The SA node is located in the right atrium and the depolarization follows tracks to the left atrium and the atrioventricular node. The AV node can automatically depolarize, but it does so at a lower rate than the SA node, so the SA node overrides the AV nodal rhythm. From the AV node, the electrical signal goes through Bundles of His and Purkinje Fibers to deliver a wave of depolarization to the cardiac muscle. These cells are modified cardiac myocytes between the endocardium and the myocardium specialized for the transmission of electrical impulse. Technically, these are not nerves, though they function similar to nerves. Beyond that, there are gap junctions between cardiac myocytes in the intercalated disks that allow for the coordinated contraction of cardiac muscle. In other words, the cells are arranged like a net and the depolarization and contraction of one cell leads to the depolarization and contraction of the cells next to it that have not yet been depolarized.
How electrons move in dumb bell 'p' orbitals?
Answer given by Ptorquemada, I couldn't do better, so credits to him. Copy/pasted: You're probably not going to like this answer much: The same way it moves in any other orbital. You're most likely being confused by the depiction of a p orbital as a "figure 8" shape and the common (mis)conception that orbitals are like orbits. In actuality, the behavior of electrons is very different from that of ordinary objects large enough for us to observe directly. The truth is that the electron in a p (or any other) orbital has a certain probability, described by the wavefunction, of being found at any particular location. In a p orbital, there is a nodal plane, where the electron has zero probability of being found ever; on both sides of the nodal plane, there is a nonzero probability of finding the electron. So how does it get from one side to the other if it can't go through the plane in between? Welcome to Quantum Mechanics, where you're not allowed to ask questions like that. (Actually, it's because you're thinking of an electron as a particle, but here is where its wave character comes out; it's on both sides at the same time, and only when you attempt to detect it does the wavefunction collapse and give it a definite location, which has to be on one side or the other.)
Does the sedimentation rate-westergren in a CBC tell if you have Hodgins Lymphoma?
No the erythrocytes sedimentation rate, (ESR), Westergren method is a non specific blood test that indicates inflammation or infection in a person , however it wil not indicate what the cause of the test result is.The following is a section from wikipedia that makes mention of the SED rate in hodgins lymhoma.Other studies have reported the following to be the most important adverse prognostic factors: mixed-cellularity or lymphocyte-depleted histologies, male sex, large number of involved nodal sites, advanced stage, age of 40 years or more, the presence of B symptoms, high erythrocyte sedimentation rate, and bulky disease (widening of the mediastinum by more than one third, or the presence of a nodal mass measuring more than 10 cm in any dimension.)To learn more on this subject go to the related link(hodgins lymhoma.) belowA sedimentation rate is blood test that can detect and monitors inflammation in the body.It is a measurement of the red blood cells (erythrocytes) sedimenting in a tube over a given period of time. this test is referred to as an ESR.Red blood cells settle in the bottom of the test tube given time leaving leaving the blood serum visible above. The sedimentation rate is simply how far the top of the RBC layer has fallen (in millimeters) in one hour. The sedimentation rate increases with more inflammation.The normal sedimentation rate (Westergren method) for males is 0-15 millimeters per hour, and for females is 0-20 millimeters per hour. The sedimentation rate can be slightly more elevated in the elderly and is much lower for children.
