Cell Definition and 899 Threads

OK, here's the deal: I was wondering, "what is the general opinion, ethically, on embryonic stem cell research?" so, I made a poll When you vote, use your own opinion, and afterwards, post what you voted and why. please be informed, or don't vote/post.

Homework Statement Is mitosis the same as cell division? Homework Equations The Attempt at a Solution I want to say yes because mitosis is a type of cell division and when you speak of mitosis, it's usually referred to cell division. However, mitosis doesn't include all of cell...

What sort of circuit would I have to set up to figure out the internal resistance of a dry cell? Also, what would i need to be measuring and doing etc, to find this internal resistance? Thanks, Jack.

Homework Statement Current solar-panel technology has the efficiency of converting 12% of the solar energy to electricity. Given that on a sunny day in Arizona the average solar radiation energy flux is 1.0 kW/m^2 , and that the area of Arizona is 3.0 × 10^5 km^2 , 1. What percentage of...

Hi Everyone, I've been trying to find a load cell for a report and I need one with a maximum capacity of >200Kg and and accuracy of 10 grams or better (used in compression). I've taken a look on the web and the highest accuracy I can find is about 0.03% of the maximum capacity; which with a...

Homework Statement 20. The probabilities that a certain type of cell produces during its lifetime 0,1,2 cells of the first generation are 1/4 , 1/2, 1/4, and any cell of the first generation produces cells of the second generation under the same conditions. Find the probabilities...

I'm planning on making a simple solar powered cell phone charger for a demonstration speech in my gen-ed speech class because it seemed like it would be fun at least. The best solar panel I could find for cheap has an output of 6v and 50 mA. My cell phone charger has an output of 5.0v and 700...

Homework Statement A cell membrane is composed of lipid molecules and approximately 10.29 nm thick. If the dielectric constant of the lipid is kappa= 5 , what is the approximate capacitance of a spherical cell that has a diameter of 10.29 micro meters? Homework Equations E=KQ/r^2...

Homework Statement Two learners, Wade and Tang are working together on a project. They were asked by their teacher to assemble a galvanic cell that would produce a large enough voltage to light up a 1.5V bulb. They are allowed to use two electrodes, one of which must be a zinc electrode...

Hi, I am designing an amorphous silicon solar cell and i wanted some pointers on how I should calculate the width of the intrinsic layer to get maximum absorption of light into my cell. I have designed my cell with the doping concentrations of p and n layer as 10^18 and 10^15 respectively.

I am using a cellphone with 2 accelerometers in it. So, in all I have 2*3 readings from accelerometer ( 3--> x,y, z axis). I am trying to find the orientation (up and down) and the tilt/angle of the cell phone. The cell phone won't be kept in the horizontal surface, instead it would be rotated...

Hi guys, I am currently doing a university project on the reliability studies of a a-Si thin-film solar cell with specs of 3V@25mA. However, I am stuck at the first step, which requires me to obtain the I-V characterisation curve to derive the parameters of Isc,Voc and Pmax. My lab has a...

How to obtain the I-V characterisation curve of a-Si solar cell?? Hi guys, I am currently doing a university project on the reliability studies of a a-Si thin-film solar cell with specs of 3V@25mA. However, I am stuck at the first step, which requires me to obtain the I-V characterisation...

Homework Statement A photovoltaic cell has area 80 sq cm and efficiency converting energy in the form of sunlight to electricity of 7%. The sun's intensity is 800 W / sq m and the rays are perpendicular to the cell's surface. What power will be produced by this cell (in W)? Take care in...

Superbooster™ cell phone "booster" fraud The following image is a freeze-frame from the product ad, as found on the parent website of the marketing company who makes and sells the product: http://img33.imageshack.us/img33/2258/superbooster.jpg This is an image of a type of RF-based EAS...

Hi is there anyone here who does work with stem cells/has done it, who knows places that will do it privately, for any purpose as opposed to just some sicknesses? Maybe someone who could elaborate more on it/who could pm me their contact info or anything? thanks

I want to make my own small and simple walkie talkie with a range of 2Km or more. I can't find a small and simple schematic of that. I also want to make a cell phone jammer which will also be simple and small. I have a small knowledge and experience about electronics so suggest me a circuit...

Hey guys. I am going to finally catch up with technology and get a smart phone of sorts. But I have a dilemma: I have been with Sprint for ~7 years. It is part of a family plan, so it ends up being like $40 / month for my share. I am eligible for an upgrade and could get a Blackberry or...

Considering the thermodynamic law of entropy it would be considered impossible for a sub-infinite number of genetic combinations to code for a single cell, in light of the massive amounts of early UV radiation. Even considering genes of DNA and RNA allowed to replicate in a lab, the...

Could replacing one or more parts of the cell, using artifical and or/biological material for the replacement(s) possibly make it so mutations did not cause aging in a way where the aging from the mutations is permanent except if/when organ replacements are done. Why/why not. if someone answers...

Homework Statement General questions about how cancer affects the cell cycle... 1) Does cancer actually speed up the individual phases of mitosis (prophase, metaphase, anaphase, telophase) ... ie metaphase occurs 100x sooner following prophase in a cancer cell compared to a normal cell...

I use to do XRD from room temperature to High temperature and then cooling again at room temperature. I see there is constant going to the right for all the peaks and also their intensities are decreasing, also the width of peaks is becoming larger. I would like to interpret those data and also...

How big would a solar power cell need to be...to power a 0.5 A load (240v)? How about 1 A?2? 10? 50? Just curious.

A couple of decades ago it was feared that the Dutch economy would slowly smother in the traffic jams. The invention of the cell phone however appeared to have countered that. People just continue doing business by cell phone, while waiting in the traffic jams. I just discovered that cell...

Hey guys, I am trying to find what type of hospital jobs are suitable for a person who will have a B.Sc in cell microbiology. There are jobs (some have been stated many times in this forum) such as doctor, pharmacist, etc, but are there more? I know that a B.Sc will not get me much in a...

Homework Statement I am doing an investigation on the factors that affect the voltage of a galvanic cell (or daniell cell). I have two beakers with zinc and copper strips and zinc sulphate and copper sulphate. How would there be an electrical current produced (significantly lower however) with...

This will be the next thing that one is not supposed to while driving. Air Writing: Next Big Thing in Cell Phones? http://news.yahoo.com/s/livescience/20090610/sc_livescience/airwritingnextbigthingincellphones

ive noticed several times that when I am watching tv, and my phone rings, that my ringtone will actually play through my tv speakers. does anyone know why that happens?? thanks.

In order to build a QE measurement system, I want to confirm the following issues: (1) Is collimated light required for QE characterization of the entire solar cell? How "bad" it could be if having Gaussian beam? (2) It seems LBIC is most common for QE mapping. Is it possible to use...

Anyone one here, knows any link where there will be a diagram of the epidermal cell of the root hair cell? If not, could you please explain to me everything about the epidermal cell of the root hair.

I'm working on a project for class. The project requires a certain level of difficulty. The idea: A system that would theoretically monitor the current through EACH solar cell in a Photovoltaic panel to ensure it wasn't shaded or defective.(For those that don't know, when a solar panel is...

From the UK's Sunday Times:

Hello, I'm doing work in Fuel Cells and am having difficulty with a simple issue; the Nernst Voltage (E) is greater than the Standard Potential (EO) The only electrochemical reaction considered is H2 + 0.5O2 --> H2O The Nernst equation for this reaction is E = EO - (RT / 2F) ln (PH2O / (PH2...

Imagine that it is possible to design cells of varying size. A cell is to be designed with a membrane that has a stable number of open channels. To this end, the number of channels must meet the following condition: the standard deviation of the number of open channels shall be no more than...

I am beginning study Crystal structure. I am finding K-points of unit cell each lattice structure. I have to simulation bandgap structure of all lattice structure. Tell me please! Thanks sansab

Hi I'm quite new to MATLAB and I'm stuck on a problem which I think is probably relatively simple. Any help much appreciated! Right, I have 2 cells, both of dimension 51x1 called n_cbc and n_load. Each of the 51 rows in the n_cbc cell contains a 5x1 matrix. Each of the 51 rows in the...

Hi, I am trying to write a model that simulates calcium input and output based on the induced strain, strain rate, and frequency of the applied strain. But before I can do that, I am trying to know more about the biophysics of the cell. How does the calcium pump/channel physically react...

what happen's if one cell organelle quits working how does it affect the cell?

Hey people, I wanted to try this experiment. My experiment is to shine a light on a solar cell and try to figure out the frequency of the light. I do have some idea on how to do this using energy concepts. E_i+W_n_c=E_f E_i= initial energy in the system (joules) W_n_c= work that...

Explain why cell potentials are not multiplied by the coefficients in the balanced redox equation. (Use the relationship between delta G and cell potential to do this.) i know that cell potential is an intensive property but i don't know how to explain why you don't multiply the the cell...

Homework Statement 2 H2(g) + O2(g) 2 H2O(l) K = 1.28e83 As temperature increases, does the maximum amount of work obtained from the fuel cell reaction increase, decrease, or remain the same? Homework Equations 1. G = -RTln(K) 2. dG = dH - tdS 3. w_max = dG The Attempt...

Considering the fact that the standard cell phone frequency range (0.8-2GHz) is less than the atandars Wi-Fi range (2-5GHz), why are people afraid of cell phone radiation and not of wireless networks?

Homework Statement The membrane surrounding a living cell consists of an inner and an outer wall that are separated by a small space. Assume that the membrane acts like a parallel plate capacitor in which the effective charge density on the inner and outer walls has a magnitude of 7.31 x 10-6...

A baby is born weighing 4kg. It starts its life from a single cell, which then divides into 2 cells, each of those two divide then again, and so on. Use information from the problem above above to calculate how many diffusion process happen in the 9 months of pregnancy. Is this a realistic...

Materials -- unit cell question "In terms of the atomic radius, R, determine the distance between the centers of adjacent atoms for the BCC crystal structure along the [111] direction." I got the answer 4R but it is wrong. I came up with this by assuming that atoms touch each other in the...

Homework Statement Describe a wet cell battery and explain its operation? How would would ensure getting maximum voltage. Assume you are only permitted a single cell.The Attempt at a Solution I got the first question, but i don't get how to answer the second question. i know that when a wet...

Researchers have found that cell phone signals can alter four essential features of fertile, grade A sperm: 1. Mobility -- How well they move; 2. Viability -- How tough they are; 3. Sperm count -- How many there are; 4. Morphology -- Proper composition. In men who use cell phones, multiple...

1.If I double the diameter of a cell, by what factor does the capacitance of the membrane change? 2. Help! The Attempt at a Solution

[SIZE="3"]Ok, well there were about 75 questions I had to do. I've done most, but have a lot of blanks. I've checked the internet and my book. But still nothing. It would be great if you could help me :wink: I am currently in Pre-IB Biology in 9th grade. These are not questions that we...

While I'm not at all surprised by the results of the study reported in this article with regard to how badly distracted drivers are while on the cell phone, even hands-free, I am a bit surprised it was so much different from having a chatty passenger in the car. I would have thought a passenger...