A character in Dragonball Z. Created by combining the DNA of Vegeta, Piccilo, Son Goku, Gohan, Freeza, and several other powerful people.

Comes from the future in a time machine (apparently stolen from Trunks in an alternate reality) to destroy the Earth (like most other enemies).

Gets his ass kicked by Piccilo, then crawls away.

ASCII Art of a typical plant cell:

   .-----------------.----cell wall (cellulose)
  // , O   ,   '   o \\    
 // o .----------.  ' \\ 
|| ' |            | O ||   vacuole (mostly water
|| o  `--.        |   ||  /  and amino acids)
||, .---. \       | ' ||   
|| /xXxX \ |      | o ||   nucleus                     
||( xxXx / |      |  ,||  /
||o\XxX / /       |O  ||
||    .--'        | ,o||
|| O |            |  o||  cytoplasm
|| '  \__________/ '  || /
 \\o ,   o   O  , '  //    cell membrane (inner wall)
  \\  .O   '  o  o  //    /
   `----------------'

organelles:
xX - chromosomes
O  - chlorplasts (contain chlorophyll for photosynthesis)
o  - starch grain (stores food)
,' - mitochondria

In wireless telcommunications, a cell can be thought of as the area served by one base station. In practice, that association doesn't need to be one-on-one, depending on what you classify as "base station". One point, though, should be mentioned: telecommunication cells usually cover an area (of various size) up to a height of a few hundred meters (at most) - which is one reason why you shouldn't use a cellular phone on an airplane.

A cell is a fixed-length packet used in ATM High-speed internet technology. To be specific, these packets are 53 bytes of which 48 is the payload*. The beauty of these fixed-length packets is that the headers do not need to contain size information, nor does an ATM Switch need to check the size of a packet to make sure it received the whole thing. This allows the ATM Switch to rapidly accept a cell and almost immediately send it back out again. This is in contrast to a router which has to check the size of a packet to know when to stop receiving and when to start sending. This is very fast.



*Why 48 bytes? The story I've heard, and believe, is that two different standards organizations each wanted the payload to be a different sizes. One wanted 32, the other wanted 64 -- they compromised.

A cell is the smallest thing that all organisms are made of (excluding things like viruses). In multi-cellular organisms, cells are specialized. Certain cells do certain things. However, all or almost all cells contain the following parts:

Nucleus

The nucleus is the nuclear membrane, nucleolus, and the chromosomes, as a whole.

Nucleolus

The nucleolus assists in the production of ribosomes.

Chromosomes

In a cell, chromosomes contain genetically encoded information in the form of chromosomal DNA (deoxyribonucleic acid).

Nuclear Membrane

The nuclear membrane controls what gets in/out of the nucleus.

Nuclear Pores

Upon close observation, you will see that the nuclear membrane is not flat, but has many dips. These are nuclear pores, through which things going into/out of the nucleus pass.

Lysosomes

Lysosomes help destroy worn parts, get rid of bacteria, and break down complex molecules. Lysosomes are actually specialized vesicles.

Golgi Apparatus

The Golgi Apparatus helps process/package/transport proteins.

Vesicles

Vesicles help transport things around the cell.

Rough Endoplasmic Reticulum

In a cell, the rough endoplasmic reticulum (ER), and the smooth ER extend all around the cell, and serve as a "highway" through the cell. The rough ER also modifies the proteins created by ribosomes.

Smooth Endoplasmic Reticulum

The smooth ER, unlike the rough ER, does not have ribosomes on it. The smooth ER is mostly involved in the synthesis of lipids and carbohydrates. The smooth ER also specializes in detoxification.

Ribosomes

Ribosomes help in the synthesis of proteins. In a cell, many ribosomes are found floating freely in the cytoplasm, but many are also found on the smooth ER.

Mitochondria

Mitochondria release energy, just like batteries. The energy is stored as ATP (adenosine triphosphate).

Vacuole

The vacuole stores food, water, minerals, proteins, and waste products. In some plants, vacuoles store chemicals that give the flowers their color.

Chloroplast

In a plant cell, the chloroplast, which is green, performs photosynthesis. The energy released from photosynthesis is also stored as ATP.

Cytoplasm

In a cell, cytoplasm, which is 65% water, contains cell parts, enzymes, and dissolved nutrients. The water is a great environment for the biochemical reactions occurring inside the cell.

Cell Wall

The cell wall, found only in plant cells, gives the cell its shape. It allows plants to stand up without a skeleton or other support.

Plasma (Cell) Membrane

The plasma membrane, with its porous surface, controls what gets into/out of the cell. In its function, it is much like the nuclear membrane.

Cytoskeleton

The cytoskeleton is composed of many thin fibers, and helps support the cell. The cytoskeleton can be disassembled and rearranged as needed.

For a long time, I was tricked by cell diagrams. Cell diagrams (such as the one above, written in ASCII, or the more spectacular multicolored diagrams that cover an entire page that you see in biology textbooks) are very interesting to look at, communicating the many different features of a cell, but also showing the neat interlocking way that the internal organelles communitcate with each other and the extracellular area through the clean process of proteins working through electrostatic, "key-in-the-lock" forces.

When I thought about it more, and really compared the size of a cell to the speed of the material inside, I saw that any attempt to compare the workings of the cell to the well worn metaphor of a billiard ball table was projecting a macroscopic model onto something it really wasn't appropriate for.

First, let's look at the size of a cell. A cell in a multicellular organism is usually between 10 and 100 micrometers. I will take 10 micrometers as my sample cell size. The atoms inside of this cell are around 0.1 nanometers, while a small molecule, such as water, sugar or an amino acid is about 1 nanometer. Proteins can go up to 10 nanometers. Which means that using linear measurements, the parts of the cell are from 1/100,000th to 1/1,000th the size of the cell. Of course, cells exist in three dimensions, so if we cube (more properly, we would use the formula for sphere volume, since they are roughly spherical, but cubes will do well enough for our estimate here) these size differences work out to a cell being a billion times larger in volume than its proteins, and some quintillion times larger in volume than the individual atoms contained there.

Personally, I find it hard to wrap my mind around numbers such as these. Translating these numbers into measurements that we may be familiar with will provide some sense of scale, although perhaps not much. If we were to take one of our atoms, at a tenth of a nanometer, and blow it up 100 million times its size, to a centimeter (roughly the size of the d10 I have in my hands right now), a sugar molecule or lipid would be about ten centimeters, the size of a tennis ball, and proteins would be 100 centimeters, or the size of a beach ball. Increasing the volume of the cell 100 million times would make it a kilometer on each side. So to put a cell in context, it would be like an orb a kilometer in diameter, full of objects ranging from the size of marbles to the size of beach balls, all moving around inside.

Even this image isn't all that hard to understand, since it can be roughly approximated by imagining one of those Chuck E. Cheese rooms full of balls, and then just imagining your favorite sports stadium filled in a similiar fashion (a very nice thought!). However, an additional factor to take into consideration is the tremendous speed of the particles inside the cell. It took me a while to realize this, but the normal brownian motion of atoms and small particles, also known as heat, is actually around the speed of sound. After all, when we shout, we aren't accelerating the air to the speed of sound, we are just creating waves in a medium that is already traveling at that speed. The speed of sound is roughly 1000 kilometers an hour, or about 300 meters a second. Which means that the normal atoms inside your body are moving at a speed that roughly translates to 3 trillion times the size of their body, every second.

So, what would happen if we were to increase the speed of our atoms as much as we were increasing their size in our analogy? If an atoms travels 3 trillion times the size of its body every second, what would that look like if it was a centimeter in diameter, instead of a tenth of a nanometer? Three trillion centimeters is 300 billion meters, or 300 million kilometers, which is a little more than the distance from Mars to the Sun. Thus, if an atom was a centimeter across, it would be moving at a velocity of 300 million kilometers a second, or roughly a thousand times faster than the speed of light.

Thus, if we were to visualize a cell as being an orb a kilometer wide, it would be full of around quintillion particles, all moving at a thousand times the speed of light. This, of course, doesn't bring into question the issues of resonance and electrical and ionic forces. But, put at this level, I have to admit that at least personally, I can't really understand the inner workings of a cell. And it is for this reason that whenever people shoot down alternative medicine theories based upon the a priori assumption that a cell can be analyzed in the same way as a "game of billiards" or some other macroscopic mechanical metaphor, I tend to think that perhaps they have misplaced their skepticism.

the Cell is also a new microprocessor design by IBM with Sony and Toshiba, complete with a distributed computing architecture. While at the time of writeup no units have appeared in actually shipped products, the Cell has been officially announced and its architecture has been widely discussed online.

The Cell, for what is known, is a design optimized for speed on integer operations. The design is, in a sense, "simpler" than current Pentium designs, and it leaves a lot of responsibility to the compiler, that must produce code that exploites the unique Cell architecture.

A Cell unit will be composed of one controlling unit, similar to a PowerPC processor, the EIB (Element Interconnect Bus) a very high speed crossbar interconnet (multi Gigabit/s speed) and eight APUs, that's to say Attached Processor Unit. The APUs are vector processors, each one with 128 Kilobytes of local storage and 128 registers, each 128 bits wide. There is no L1 cache, or other forms of caches. The idea is to devote as much of the silicon as possible to the actual execution of instructions.

The EIB handles all off-chip communication.

IBM claims that one single Cell processor will be much faster than the fastest Pentium processor in production. But the real power of the Cell architecture will be that it is supposed to make easy the assembly of multiprocessor machines. IMHO, this thing is really going for Intel's throat - at the very least it will be able to emulate a Pentium.

Applications: the PlayStation3, and consumer electronics by Toshiba. Anything that requires heavy duty integer performance, such as real-time 3D and encoding/decoding of multimedia content.

Cell (?), n. [OF. celle, fr. L. cella; akin to celare to hide, and E. hell, helm, conceal. Cf. Hall.]

1.

A very small and close apartment, as in a prison or in a monastery or convent; the hut of a hermit.

The heroic confessor in his cell. Macaulay.

2.

A small religious house attached to a monastery or convent.

"Cells or dependent priories."

Milman.

3.

Any small cavity, or hollow place.

4. Arch. (a)

The space between the ribs of a vaulted roof.

(b)

Same as Cella.

5. Elec.

A jar of vessel, or a division of a compound vessel, for holding the exciting fluid of a battery.

6. Biol.

One of the minute elementary structures, of which the greater part of the various tissues and organs of animals and plants are composed.

⇒ All cells have their origin in the primary cell from which the organism was developed. In the lowest animal and vegetable forms, one single cell constitutes the complete individual, such being called unicelluter orgamisms. A typical cell is composed of a semifluid mass of protoplasm, more or less granular, generally containing in its center a nucleus which in turn frequently contains one or more nucleoli, the whole being surrounded by a thin membrane, the cell wall. In some cells, as in those of blood, in the ameba, and in embryonic cells (both vegetable and animal), there is no restricting cell wall, while in some of the unicelluliar organisms the nucleus is wholly wanting. See Illust. of Bipolar.

Air cell. See Air cell. -- Cell development (called also cell genesis, cell formation, and cytogenesis), the multiplication, of cells by a process of reproduction under the following common forms; segmentation or fission, gemmation or budding, karyokinesis, and endogenous multiplication. See Segmentation, Gemmation, etc. -- Cell theory. Biol. See Cellular theory, under Cellular.

 

© Webster 1913.


Cell (?), v. t. [imp. & p. p. Celled (?).]

To place or inclosed in a cell.

"Celled under ground." [R.]

Warner.

 

© Webster 1913.

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