Cells Definition and 429 Threads

If eight flashlight batteries in series have an emf of about 12 V, similar to that of a car battery, could they be used to start a car with a dead battery? Why or why not? My friend posed to me this question and then I just sort of stumbled and was dumbfounded. I answered it by saying the...

Hi, could someone care to explain two things: 1) Whats happens when the resistance load of a circuit powered by a PV cell generates a higher voltage then that produced by the PV cell (does band gap get affected). 2) Why does current drop near the Open Circuit Voltage? Surely the generation...

Could someone PLEASE explain in simple language "procedures whereby scientists modify the germ plasm of plants and animals by the use of X rays?" And, how might that effect chromosomes? If you do not know, please advise where I can find this information. I am not a student and this is related...

Just curious as to why you don't find heat pipes or any passive cooling in larger PEM type fuel cells. I have seen them used in methanol fuel cells but not FCs for hydrogen. Is there a good reason for this? Is it because the power density of fuel cells is typically higher than that in many...

What is the difference between dendritic cells and FOLLULAR dendritic cells? where are these found in the periheral tissues? thanks

I know that smooth and cardiac muscle cells (myofibers) are connected to each other by gap junctions. How are skeletal muscle cells connected to each other (to transmit the AP)? Thanks, any responses appreciated

For those of you that arent very familiar with PEM fuel cells, their shortcomings basically revolve around the carbon/platinum membrane and is essentially the "heart" of the fuel cell. But why does a fuel cell need a membrane to function? If you think about it, just about all energy conversion...

I've learned about memory B and T cells. I'm wondering how many of each a person has for a specific antigen? How long do they live?

How many molecules have a white blood cells and red blood cells? What are the chemical description and information about these above molecules?

How much electrical energy does it take to manufacture a solar cell? I'm curious about the break-even time. Silicon boules are grown in an over--probably electric. More machining follows. If the frame is aluminum, it's smelted in an electric arc furnace. This is really an oversimplifed...

If one gene is inserted into the sequence of a second gene, will both genes by transcribed in the eukaryotic cell?

Why do muscle cells have more golgi bodies than, say, cheek cells?

Hi, I was looking around at graduate schools and was curious if anyone knew of places where they are doing research into organic electronics or organic photovoltaics? I found a research department at MIT and Stanford, but I was looking for something perhaps one tier below that. It...

could anyone shed some light on the following... the language might not be too precise here, but I'm trying to get a feel for the subject in a battery one terminal (metal) has an excess on electrons which have come from the other +ve terminal (metal), this causes a difference in potential...

Ultraviolet light can kill skin cells but infrared light only warms skin cells even though both types of lights are from the sun. Why is this, explain using the photon theory...?

Hi, Can someone provide a list of anucleate cells in human body? i know platelets and red blood cells are anucleate. Are there more? Thanks a million.

Do germ line cells accumulate DNA Damage like the rest of the body? I've heard things about them that make them seem to have very different characteristics to the rest of the body. Ie could germ line cells, or anything, contain your original DNA when you're like 50 or 100, or would the only DNA...

You are required to plan an investigation to find out the rate of glucose uptake by yeast cells varies with glucose concentration material resources - 10% glucose solution - disilled water -yeast suspension - Benedicts reagent I have done the introduction, apparatus required, but I am...

What does the operating temperature of a fuel cell mean? Is this the temperature the cell generates or the temperature the cell is brought to so that it can operate? I see articles that state operating temperatures for different fuel cell systems---i.e. solid oxide 600 to 1000 C, phosphoric acid...

1) Will yeast cells or corn seedling have a higher metabolic rate when compared on a mass specific basis? 2) How will decreasing the amount of glucose affect the rate of ATP production by the cells if the amount of yeast is held constant? Answer: the rate of ATP production will...

I understand how we get microspheres and coacervates, which aren't really living, but how do we get prom these to the first prokaryotes? I understand that once you have the prokaryotes they can coexist to form eukaryotes and so forth, but I can't seem to find out what that little step is that's...

Is Plasmodium an example of a syncytium, or is there a slight difference between the two terms? Thank you.

Can you force older cells to express more delta protein? Would the cells expressing more delta protein be good or bad?

[b]1. Homework Statement [ Six cells are connected in series to form a battery. Each cell has a rating of 1.5 volts and 1 amp. AWG 18-gauge wire joins the positive terminal of the battery formed by the series of cells to an indicator lamp 300ft away. Another 300ft length of AWG 18 wire runs...

Do all cells and microorganisms fulfill the criteria of life? Homeostasis Organisation Metabolism Growth Adaption Response to Stimuli Reproduction I'm asking, because I know that there are animal species which don't fulfill all those criteria (I know a mule can't reproduce) and I was...

What kind of stem cell technology is being used in humans right now and by what places? I mean some stem cell technology is being used currently in humans right?

I read in maplin.co.uk that SR-41 button cells are superior to LR-41s. In what ways and by how much? Thanks

i have a question. please tell me the Miller Indices for Crystal Planes of HCP unit cells +packing density of it. thank you

Iam doing an experiment on voltaic cells in particular Iam studying the effect that the thickness of the salt bridge has on the emf of the cell over time. iam thinking that the thicker the salt bridge the longer it will last. I think that will happen because maybe there is more surface area...

Hi there! Could anyone help me out with this question? Which steps should I take in solving this question? Chemical cells can produce quite large charge flows for substantial times before their chemicals have all reacted. If zinc is the metal losing electrons under chemical attack, what mass...

Sex cell? Quick question: Does every sperm cell in a male testicle contain the same genes, or can some sperm cells contain different genes, even though they are from the same person?

Hi! I'm django, new member. Right, I would like to talk about fuel cells. At first glance they are great, right! 99% fuel efficieny. But what most peopkle don't realize, is that although hydrogen might well be the most predominant element in the Universe, it is not available on Earth in...

So my question is what is the difference between these cells? This always confuses me. I know that electrolytic cells are nonspontaneous and that their cathode is negative which means that electrons are going against their gradients here. I am also aware of the fact that a galvanic cells is...

The set S={1,2,3,4}, there are 4 cells. What is the probability for 2 different digits (from S) to appear in 4 cells? Example: 1,1,1,2 =>good 3,4,4,3 =>good 2,4,2,2 =>good 1,2,3,4 =>not good 1,2,3,3 =>not good 1,1,1,1=>not good

The problem http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/animations/CuZncell.html After veiwing the animation found at the website above answer these questions: Is there an electron transfer between species? Which species is losing electrons Which species...

Homework Statement Use half-reactions and E's to determine the result of storing a solution of CuSO4 in a tin container. Homework Equations [Table of Standard Reduction Potentials of Half-Cells] The Attempt at a Solution My question isn't exactly how to do this question. I was just...

In a galvanic cell is it the anions from the electrolyte which is attracted to the cathode or is it the anions produced from the anode dissolving which flow to the cathode?? Also it mentions that the charges increase in energy as they pass through the power supply and they decrease when they...

Hi everyone I need to know where can I buy Peltier cells in internet. can someone help me? Thank in advance

I have an upcoming paper to write for my solar cells course. The question is something along the lines of, if we have a p-n junction which side should we shine the light on for efficiency? Should it shine on the p side or the n side? Efficiency at this point is defined loosely, and can range...

Homework Statement I have got a battery with two half cells. One cell with. A silver rod in a 100 mL AgNO3 0,025 M solution. One cell with. A zinc rod in a 100 mL Zn(NO3)2 0,150 M solution. So my question is what reactions happen? And which reaction is the electricity providing...

I am thinking I should study electrical engineering as well as materials engineering up to a bachelor level; is this a wise plan if I hope to design solar cells. Also, how easily could I collaborate with others to do research in order to gain connections to get such a job, or at least related...

In a http://www.sciam.com/article.cfm?chanID=sa003&articleID=CF2AA0B2-E7F2-99DF-34CD01DE3E68F8ED&ref=rss", it says: What do they mean when they say 10,000 genes "could be active"? What are these genes doing in the brain cell which is interpreted as 'being active'?

I'm a physics student trying to do a project on fuels cells. One thing I don't get is, when the atom goes through the electr-- whatever, how does it separate into electrons and protons. I thought the only way to separate electrons from the nucleus is by extreme heat and pressure, like that...

Nutrients in cells question?? This question may again be too technical but does anyone now how long nutrients used for 'fuel' remain in cells (when they're not being stored - I believe they're only stored in muscle, fat and liver tissue)? For example, if a glucose molecule enters a cell from...

When spermatogonia divide by mitosis, do there telomeres shorten ? I am just trying to ask if reproductive cells age as well as with the rest of our bodies cells ? If so wouldn't a baby born from old parents have a shorter than average life expectancy due to older or more aged DNA ?

My Bio textbook says that, by introducing the virus coat protein gene into a plant cell the cell becomes virus resistant. How is that possible?

I've only taken high school biology and I'm actually a computer science major, but I've had an idea rolling around in my head recently and I think it might be better realized if I approach the problem from a biological standpoint. I'm sort of stuck at a particular problem that I can't seem to...

Greetings! I have read/heard from various sources that none of the cells in my (or any other human's) body now are the same as they were seven (At least one source said nine years) years ago. I remember reading from one source that some cells don't "die" but all of the separate parts are...

Biology Help ! Female cimpanzees often mate with more than one male. The different males' sperm cells race each other to reach the egg first. Both Modja and Tatu have mated with Tanu in the last hour. a) In which part of a sperm cell and an egg cell are the genes found? b) What do genes...

I was checking out diamond anvil cells and i have few questions. I have been on this sites: http://www.physlink.com/Education/askExperts/ae483.cfm (1) http://www.matweb.com/search/SpecificMaterial.asp?bassnum=CDiamA (2) http://merkel.zoneo.net/FEM/index.php?lang=en (3) 1.what is max...