Part of plant and animal cells outside the
nucleus (and outside the large vacuole of plant cells). Strictly speaking, this includes all the
organelles (mitochondria, chloroplasts, and so on) and is the area in which most cell activities take place. However, cytoplasm is often used to refer to the jellylike matter in which the organelles are embedded (correctly termed the cytosol). Most of the activities in the cytoplasm are chemical reactions (metabolism), for example, protein synthesis.
In many cells, the cytoplasm is made up of two parts: the
ectoplasm (or plasmagel), a dense gelatinous outer layer concerned with cell movement, and the
endoplasm (or plasmasol), a more fluid inner part where most of the organelles are found.
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