Some spicules are formed of the mineralized substances calcium carbonate and silica, while others are made of an organic substance called spongin. Sponginskeletons<span> were and are used as scrubbers in bathtubs, though they are fairly expensive. The ubiquitous bathtub accessory called a lufa is NOT a </span>sponge<span>, but a plant.</span>
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Population density just represents the average number of individuals per unit of area or volume. Often, individuals in a population are not spread out evenly. ... Population distribution describes how the individuals are distributed, or spread throughout their habitat.
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The Cambrian lasted 55.6 million years from the end of the preceding Ediacaran Period 541 million years ago (mya) to the beginning of the Ordovician Period 485.4 mya. Its subdivisions, and its base, are somewhat in flux.
Once purified, the isolated species can then be cultivated with the knowledge that only the desired microorganism is being grown.
A pure culture can be correctly identified for accurate studying and testing, and diagnosis in a clinical environment.
Testing/experimenting with a pure culture ensures that the same results can be achieved regardless of how many time the test is repeated.
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Seeds are the result of plant reproduction. ... When pollen lands on the flower's stigma, it germinates and forms a pollen tube, which then quickly grows towards the plant's ovary. Once it finds an ovule, the pollen tube bursts to release sperm cells, which fertilize the ovule and initiate seed formation.
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