NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites.IST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites.
The contractile vacuole allows free-living protists to expel extra water. <b>The contractile vacuole allows free-living protists to expel extra water <br /></b>.
In ponds and in different bodies of stagnant water, there are not only protists, but also a variety of multicellular organisms of small or microscopic size. These forms of life are also very interesting to observe. During the observation of protists, you will surely encounter tiny multicellular organisms.