Explain the difference between a change in rise time of the postsynaptic potential vs. a change in slope. What changes in the presynaptic cell might cause these two different changes in the postsynaptic cell?
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Easy, by measuring from the postsynaptic neuron, you can see how many neurotransmitters were actually received.  Knowing the rate of neurotransmitter response, release can be determined.  Besides, its more practical to do it this way.  The derivative of the change in rise time is the slope.  In other words, the slope describes the rate at which the change in rise time occurs.  Finally, there are several factors which could contribute to both the change in rise time and the rate of change.  Namely, change in pH and introdution of various bacteria.
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this is the  answer for the two, the others, you can ask to this site\nhttp://www.answers.com/\n\nhttp://cm.bell-labs.com/cm/ms/departments/sia/jmc/pub.html\n\nhttp://www.answers.com/research%20journal%20of%20Chang%20S%20H
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I'm not 100% sure but I think your idea is correct. Longitudinal sound waves in the metal, which travel at a different and faster speed than the visible wave, reflect off the pulse or kink (because there's a discontinuity in sound speed at that point). Because the pulse is moving away, the reflected wave has a lowered frequency each time it's reflected - that's expected behavior.\n\nAn equivalent way of saying the same thing (although it seems different) is that the fundamental wavelength of the standing wave based on the length of the tape between the two endpoints: the top of the tape and the pulse, is continuously lengthening or shrinking causing the pitch to go down or up continuously like the pitch of a guitar string when the hand slides along the fingerboard.\n\nThis can't be a case of a Doppler shift caused by a moving sound source - because in that situation, the pitch would be lowered (for a source travelling directly away) but not continuously decreasing.\n\nWith respect to the other question:\n\nIt's quite certain that there can't be any difference in speed between a wave moving up or down (at a given point on the tape). The only possible effect of gravity is as explained by Epidavros, to gradually increase the wave speed at higher levels - *if* it so happens that total weight of the tape (e.g. when it's rolled up) is comparable to the spring tension.
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Unfortunately there isnt any average cell-as said before, there is variation from minutes, in the case of some immune and germ cells, to never in the case of most neurons.  But, to give you a way to answer your homework, you can say a hypothetical cell takes 24 hours to divide-there are quite a few cell types that take about this long, so you would be safe choosing this time.
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Your "thought" of movement starts in the precentral gyrus, the signal travels to the cerebellum via pontine nuclei, then the action potential is sent, but it is sloppy movement and still needs calibration.  This is done after afferent signals from the proprioceptive neurons combine with the first set of efferents and the 2 are compared.  The signals then are refined by the precentral gyrus and secondary impusles for the same movement are again sent down the pathway.
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i think that if you categorise it  under physics/biology/chemistry, you might get a better response.\n\nnevertheless:\n\nhttp://school.discovery.com/homeworkhelp/bjpinchbeck/bjscience.html
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The quantity of neurotransmitters in the terminals is kept relatively constant and independent of nerve activity by tight regulation of neurotransmitter formation. Regulation varies among neurons and is achieved by modifying precursor uptake or the activity of enzymes involved in neurotransmitter synthesis or destruction. Stimulation or blockade of postsynaptic receptors can decrease or increase presynaptic neurotransmitter synthesis.\n\nNeurotransmitters diffuse across the synaptic cleft, bind briefly to receptors, and activate them, causing physiologic responses. Depending on the receptor, the response may be excitatory (ie, initiating a new action potential) or inhibitory (ie, inhibiting the development of a new action potential).\n\nThe neurotransmitter-receptor interaction must be terminated quickly so that the same receptors can be rapidly activated repeatedly. The neurotransmitter is quickly pumped back into the presynaptic nerve terminals by active processes (reuptake), is destroyed by enzymes near the receptors, or diffuses into the surrounding area and is destroyed.\n\nAbnormalities of neurotransmitter synthesis, storage, release, or degradation or changes in the number and affinity of receptors can affect neurotransmission and cause clinical disorders
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the cell dividing force lol. theres no such force. it's a spontaneous occurence
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SURFACE AREA INCREASES\n\nIT'S VICE VERSA
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The resting membrane potential at -70mv would become disrupted, since it depends on sodium being extracellular and potassium being intracellular. One affect, say on the heart, might be heart arrythmias.
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electrical signals. "An important characteristic of neurons is that they have excitable membranes which allow them to generate and propagate electrical signals." "Membrane potential (or transmembrane potential or transmembrane potential difference or transmembrane potential gradient), is the electrical potential difference (voltage) across a cell's plasma membrane. In membrane biophysics it is sometimes used interchangeably with cell potential, but is applicable to any lipid bilayer or membrane. Hence every organelle and every membranous compartment (such as a synthetic vesicle) has a transmembrane potential (although the size of this potential may be zero)."
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C) By interfering with the electron transport chain, energy production (in the form of ATP) would be significantly reduced.  Neurons use a great amount of energy to maintain the ionic gradient that allows synaptic transmission.  In he absence of ATP, the ionic pumps, primarily sodium/potassium, would not function, the ionic gradient would break down, and it would halt neuronal transmission.
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What is the width? We can calculate the area with your information, but not the volume. The rate of rise will decrease as it fills due to the increase of area, the formula needs to be shown on your homework page when it is turned in. The resulting formula is linear and the resulting point is defineable with a little more info.
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The fact that he took his return trip later just complicates the problem. The question can be restated as one person leaves from the top of the mountain and one person leaves from the bottom of the mountain. They leave at the same time. Explain why, if they follow the same path, they will run into each other each other at some point. Stated this way, it is obvious, right?\n\nIf you want a more rigorous solution, here you go. This is a continuity question. Let f(t) denote the distance *from the bottom of the mountain* at time t on the trip up the mountain and let g(t) denote the distance *from the bottom of the mountain* at time t. Change your units so that your time starts at zero (so 8AM is t=0) and you make it up the mountain in time 1 (so 1PM is t=1) and your distance from the bottom to the top of the mountain is 1. With this set up, g(x) lies in the interval [0,1] for every x in the interval [0,1], and the same holds for f(x). Consider the function g(t)-f(t). The physical interpretation makes it clear that f(t) and g(t), hence g(t)-f(t), are continuous functions of t; that is, you don't just disappear at one point and reappear at another point without having travelled through every point in between. g(0)-f(0)=1-0=1>0 and g(1)-f(1)=g(1)-1<=0. The intermediate value theorem tells you that there is some time t_0 such that g(t_0)-f(t_0)=0. That is, there is some time t_0 such that g(t_0)) = f(t_0). Your deja vu moment happens at time t_0.
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i'm not sure exactly what you mean. \n\nthe slope is the slant of a line or rise over run.\n\nhope this helped!
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It is about negative feedback which involves:\n\n* Sense that temp has deviated from the homeostatic set point\n* That message is sent to the integrating system in the brain\n* Then an action potential is sent to the effector target to stimulate    muscles contraction to get the temp back up to the set point
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Nervous system is much faster in their rate of control mostly because of the way they communicate.  Nervous system communicates via neurotransmitters that are sent from one neuron to the next at a synapse.  This neurotransmitter, such as acetylcholine, will cause ion channels to open and an action potential to take place.  The rate at which these action potentials take place determines the action or sense that your nervous system transmits.  The endocrine system, on the other hand is a lot slower because the hormone molecules it sends out have to find its way to the effector organs.  To do this, the hormones have to travel through the blood system, reach the organs, and then bind to the cellular receptors.  Even after this has happened, these endocrine hormones tend to cause cascades in target cells to take place before the initended effect takes place.  These cascades include tyrosine kinase or g-protein coupled receptor phosphorylation cascades that ultimately result in transcription and translation of genes.  This process also is a lot slower than the process of action potential in the nervous system.