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Salient: Victoria University Students' Paper. Vol. 25, No. 3. 1962.

The Living Cell

The Living Cell

The study of the living cell is so complex that when it began to develop as an independent research area it soon sub-divided. Each of the separate divisions investigated a narrow aspect—structure or chemistry or morphology. But the cell is a self-contained entity, and researchers found that not only must all these biological sub-divisions be linked, but that other sciences—chemistry and physics—must be called on for their contributions. In one laboratory the cell is subjected to extremes of cold and heat, in another to ultraviolet rays. In the basement, behind thick concrete walls, it is exposed to powerful X-rays. It is simulated with electric current, whirled in high-speed centrifuges, poisoned, dismembered.

One researcher specialises in transplanting the nuclei of amoebae. This must be done to deter mine the relative importance of the nucleus and the cytoplasm in the life of the cell. The transfer is done with a micro-manipulator attached to the microscope. At the operating end of the manipulator are a minute loop and glass pin. The amoeba is driven into the loop and then with the pin the nucleus of one amoeba is carefully transferred to another. The operation takes the utmost delicacy and look a year to perfect.

At the turn of the century, re searchers noticed mat a cell subjected to the light of a mercury lamp radiates a barely perceptible violet glow. This phosphorescence was so weak and varied so little from living to dead matter that scientists did not see the possibilities it offered for peering into me cell until it was suggested that the faint violet glow was actually part or a much stronger radiation in the invisible spectrum, readily detectable on a photographic plate.

A group of biologists made a series of experiments with a Specially designed and built microscope and made an important discovery—that the brilliance of the phosphorescence is determined by the condition of the cell. It is the cell signalling, so to speak, how it feels.

Now comes the problem of reading these signals, a very difficult job, but it has been found that the phosphorescence of blood corpuscles differs in a healthy and an ailing body. The blood cells of an irradiated animal emit a specific phosphorescence. Thus, synthetic cytology in which biologists co-operate with physicists, is beginning to uncover another secret of the cell.

Frozen Sleep

We have no normal parallel for cold as intense as —183 degrees C. (—297 degrees F.) and it has been taken for granted that no living organism could stand temperature that low. Yet it has been demonstrated that a European corn borer caterpillar adapts itself so that it can stay alive for many days in liquid oxygen at —297 degrees Fahrenheit.

Place a flower in liquid oxygen, take it out, tap it with a hummer—it breaks with a silvery tinkle. Drop a live frog into liquid oxygen, take it out after a few minutes, drop it on the ground—it cracks like u piece of thick glass. Experiments like these can be carried on indefinitely, and always with the same conclusion—that living tissue freezes at these low temperatures. The normally constituted cell is 70-80 per cent water, and this water turns into ice crystals that tear the cell and structures.

Given the same treatment the corn borer caterpillar becomes as cold and brittle as an icicle. If broken open, white crystals of ice are found inside the chitin shell. It is lifeless and pounds to dust in a mortar like sugar or salt. But let the frozen caterpillar thaw and a miracle takes place—it gradually comes to life. It has been proved that the complete crystallisation of water in the cell of a complex organism in conditions of deep cooling does not kill the cell if it has undergone preliminary adaption. The caterpillar used in this experiment had been trained to withstand cold.

Aside from its philosophical interest this study is important for theoretical biology, for medicine and for practical agriculture. It also has a bearing on the exciting question man has long asked him self—is there life on other planets?

Our earth is fortunate because it receives just enough heat to create and maintain life. Conditions on the more distant planets are much more severe. Jupiter's temperature is 138 degrees C. below zero (—216 degrees F.). On Mars, the planet that science fiction writers have populated with intelligent beings, the daytime temperature does climb to 25 degrees C.; at night, however, it drops to —40 degrees C. even in the warmest zones.

But the adaptability of the living cell is evidently greater than we had thought. It may be that even the coldest spots on Mars have strange inhabitants who live actively during the day and fall into a state of anabiosis in the bitter cold of the planet's night. Sooner or later a living cell from outer space will be studied through a researcher's microscope for the answers.