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of both animals and plants – a common physical basis of the life. This reduction
of life phenomena established the life science, biology.
The physical chemists tell us that protoplasm consists of matter in the
colloidal state – a condition of matter that chemists have long been familiar with
in the inorganic world. A colloid has been described as matter divided into
particles larger than one molecule and suspended in a medium of different
matter. Therefore, butter and cream are each colloids: the former consisting of
water finely divided and suspended in oil, and the latter essentially of finely
divided oil in water. But protoplasm is a stupendously more complex colloidal
system. It comprises not two, but very many substances, some in simple and
others in highly complex molecular form, so finely divided that they are
invisible with the ordinary microscope.
Now colloidal systems in general are characterized by tremendous surface
activity – the result of energy relations between the contact surfaces of the
particles of the different component substances. This being so, and protoplasm
being a colloid composed of very many different kinds of materials, the total
surface area between suspended substances and suspending media is very great,
and thus affords the requisite conditions for an exceedingly intricate system of
energy relations. And when we add to this the fact that at such surfaces chemical
changes, some involving changes in electrical potential occur, and also that
mechanical changes are induced by precipitation, coagulation and constant
redistribution between the suspending media and the substances in suspension,
we begin to get at last a glimpse of the exceedingly intricate and delicate
energy-transforming system that protoplast really is.
II. Remember the following words and word combinations, consult a dictionary
about the way they are pronounced:
realization понимание
unit единица
accordingly поэтому; соответствено
consider рассматривать
ultimate последний, окончательный
viscid вязкий
fluid жидкость
both… and… как… так и…
denominator знаменатель
suspended (хим.) взвешенный
medium (pl.media, mediums) среда
therefore поэтому, следовательно
finely мелко
invisible невидимый
surface поверхность
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