## cell-
Typical animal cell
Each cell consists of protein-rich material that is differentiated into cytoplasm and a nucleus. Forming a boundary around the cytoplasm is a cell membrane, which in plants and some microorganisms is, in turn, surrounded by a cell wall.
Cells were discovered in 1665 by the English scientist Robert Hooke who first observed them through a primitive microscope. Hooke coined the term "cell," in a biological context, when he described the microscopic structure of cork as being like a tiny, bare room or monk's cell.
tr>Both animal (A) and plant (B) cells have a cell membrane (1), nucleus (2), and cytoplasm (3). But in plants the cell wall is covered with a rigid coating of cellulose (4). • CELL BIOLOGY - (MATHEMATICS) In mathematics, a cell may refer to either of the following. (i) A three-dimensional
object that is part of a higher-dimensional object, such as a polychoron.
A cell is related to higher-dimensional objects in the way that a face,
or (two-dimensional) polygon, is related
to higher-dimensional objects. For example, a cell is to a 4-dimensional polytope, or polychoron, what a face
is to a 3-dimensional polytope, or polyhedron.
Often polytopes are classified simply by how many cells they have. For
example, the tesseract has eight cells,
each one of which is a cube. (ii) The fundamental spatial unit operated
on by the rules of a cellular automaton during one generation.
• MATHEMATICAL TERMINOLOGY
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