Bio 202 - Unit #3 Case Studies: 1- Blood, Heart, and Vessels 1)WHy are lymph nodes enlarged (adenopathy)? How does this fit with his CBC test? J.T’s lymph nodes are enlarged due to a high count of white blood cell count . Jt has a high white blood cell count because his body is trying to fight off an infection. 2)…
• P wave – electrical changes of atrial depolarization. • QRS complex – electrical associated with ventricular depolarization. • T wave – electrical associated with ventricular repolarization. • P-Q segment – associated atria plateau. (no electrical charge) • S-T segment – associated with ventricles plateau.…
Once the cell begins to hyperpolarize, sodium channels open up and allow sodium ions to flood into the membrane. Once the concentration of sodium ions have been let in, the sodium channel is inactivated. Once the inactivation gate is closed, potassium channels open up so the cell can depolarize. This action allows the cell to restore itself to resting membrane potential. The sodium channels then become closed, and the process is restarted and an action potential has been fully propagated.…
The different chemicals that were used in this experiment were Pilocarpine, Atropine Sulfate, Epinephrine, Digitals, Potassium, Sodium, and calcium ion concertation. Pilocarpine stimulates the effect of parasympathetic nerve stimulation by enhancing acetylcholine release. Atropine Sulfate is a drug that blocks the effect of the neurotransmitter acetylcholine which is liberated by the parasympathetic nerve endings. Cardiac muscle and skeletal muscle are both different in functionally and in fine structure. Epinephrine is the fight or flight neurotransmitter that is released to increase awareness.…
1. Point A is considered the S1 area of the graph. At this point in the graph is where the sound “lubb” is heard. At this point is when the AV closes and the semilunar valve closes. 2.…
I. Introduction Action potentials are generated as a result of a neuron’s membrane reaching a specific threshold. In order to reach this threshold, a cell must depolarize. Typically, cells depolarize with the opening of voltage-gated sodium channels. During the rising phase of the action potential, these channels allow positive sodium ions to flow into the cell in what is called the depolarization phase.…
Assignment 2: Pacemaker causes death after contradiction with MRI scan A pacemaker is a medical device that is located in the chest area to regulate abnormal heart rate. This is possible with the generation of small amount of electric impulses that sends electrodes to contract the heart at its atrioventricular (AV) node. (PacemakerDiagram) Magnetic resonance imaging (MRI) scan is a medical imaging technique that creates images from different angles the body for diagnostic purposes. The principle behind an MRI scan is a strong and constant magnetic field and radiofrequency.…
The second device is the implantable cardioverter defibrillator(ICD), which works by noticing when the heart is converting into an unwanted rhythm and shocking the heart until it returns to its normal rhythm. Although an ICD has some similarities to the pacemaker it also has some big differences. The pacemaker and ICD are both implanted the same way, just under the skin of the chest or in the abdomen. Implanting the device is a minor procedure today and is common. Most people only need to stay in the hospital a day or two.…
3. Explain the heart generates and conducts an electrical current. Page 388 The heart has its own built-in conduction system for generating action potentials spontaneously and coordinating contractions during the cardiac cycle. All the cardiac muscle fibers in each region of the heart are electrically linked together.…
Micra has created the smallest pacemaker yet. It is 93% smaller than any conventional pacemaker, which makes it about the size of a large vitamin capsule which is about 1.75g, compared to a 44 x 52 x 6mm, 23.5g pacemaker. Unlike most pacemakers that are placed in the patient's chest with leads running to the heart, Micra is implanted directly into the patient’s heart. Some of the impact on society are: Its less invasive as the Micra is placed in the heart via a vein in the leg, which therefore means that there are no chest incisions, scars or bumps.…
The force potential of a muscle is determined by the number of action potentials that arrive at the NMJ. To maximise this, oxygen and nutrients are needed. Force potential is also increased when the initial overlap of filaments is optimal, and “extends from the edge of the H zone to one end of a thick filament”.…
At 32 Canadian heart centers, a group of physicians performed a study on the effects between physiologic pacing (dual chamber or atrial) and single chamber pacing (ventricular). The researchers were trying to determine whether the physiologic pacing is superior to the single chamber pacing as previous thought. The way they would determine this is to take a sample of patients that will receive one of the above pace makers and compare the results of atrial fibrillation, stroke, or death due to the heart. The researchers gathered their sample by some specific criteria. A total of 7734 patients received a first pacemaker at one of the 32 participating clinics, of these patients only 4499 qualified to participate.…
The action potential will eventually go past -70mV and that will cause a hyperpolarization. That will cause the potassium channels to stay open and then after awhile the ion will go back to its resting level of…
In order to determine the extent to which the reversal potential for potassium determines the resting membrane potential of a given cell, a mechanism is needed to determine the change in membrane voltage across the cell in different extracellular potassium solutions. The intracellular recording technique consists of puncturing a prepared cell with a conductive pipette. The difference in potential between the extracellular electrode and the wire in the pipette is recorded and displayed on the voltage vs. time graph. Figure 1 provides an example of an intracellular voltage recording trace for a muscle fiber cell. The dip in the voltage graph occurs after the insertion of the pipette into the cell and reflects the resting membrane voltage of the…
The features of action potentials are: threshold, all or none, is regenerative, saltatory conduction and refractory period. The threshold is generated when the membrane of the cell is depolarize around -50mv to evoke the action to occur. Action potential is all or none because is either no action potential or a full amplitude of action potential. We say that action potential is regenerative since a new action potential is generated at each location along the cell membrane.…