Pharmaceutical botany - Lighthouse Survival Blog

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PHARMACEUTICAL BOTANY
istics. Similarly among the bacilli characteristic forms result as single individuals
and others which form chains of various lengths.
Rapidity of Growth and Multiplication.—The rapidity with which bacteria
grow and multiply is dependent upon species and environment. The rapidity of
the growth is surprising. Under favorable conditions they may elongate and divide
every 20 or 30 minutes. If they should continue to reproduce at this rate for twenty-
four hours a single individual would have 17 million descendants. If each of these
should continue to grow at the same rate, each would have in twenty-four hours
more, 17 million offspring, and then the numbers would develop beyond conception.
However, such multiplication is not possible under natural or even artificial condi-
tions, both on account of lack of nutritive material and because of the inhibition
of the growth of the bacteria by their own products. If they did multiply at this
rate in a few days there would be no room in the world but bacteria.
Chemical Composition of Bacteria.—The quantitative chemical composition
of bacteria is subject to wide variations, dependent upon the nutritive materials
furnished them. About 80 to 85 per cent, of the bacterial body is water; proteid
substances constitute about 50 to 80 per cent, of the dry residue. When these are
extracted, there remain fats, in some cases wax, in some bacteria traces of cellulose
appear, and the remainder consists of i to 2 per cent. ash.
The proteids consist partly of nucleo-proteids, globulins, and protein substances
differing materially from ordinary proteids. Toxic substances known as endotoxins
to distinguish them from bacterial poisons secreted by certain bacteria during the
process of growth, also occur.
SUBDIVISION III.—ALGiE
Low forms of thallophytes of terrestrial and aquatic distribution
consisting for the most part of single cells or rows of single cells
joined end to end to form filaments. They contain chlorophyll or some
other pigment, and so can use the CO2 and H2O in the same manner
as higher plants, e.g., in assimilating and providing for their own
nutrition.
Class I. Chlorophyce^, The Green Alg^
In this group the cells are observed to possess distinct nuclei and
bodies, whose pores contain an oil-like pigment called chlorophyll,
the chloroplasts. The following forms are typical : Spirogyra, Diatoms,
Pleurococcus, Volvo.x, Conferva, and Chara.
Class II. Ph^ophyce^, The Brown Alg^
Mostly marine forms showing great diversity in the form of their
vegetative bodies. Their bodies are usually fixed to some support in the