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Structure of a plant cell. Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae.Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or ...
A primitive cell is a unit cell that contains exactly one lattice point. For unit cells generally, lattice points that are shared by n cells are counted as 1 / n of the lattice points contained in each of those cells; so for example a primitive unit cell in three dimensions which has lattice points only at its eight vertices is considered to contain 1 / 8 of each of them. [3]
The cell is the basic structural and functional unit of all forms of life.Every cell consists of cytoplasm enclosed within a membrane; many cells contain organelles, each with a specific function.
A pioneering system of plant taxonomy, Linnaeus's Systema Naturae, Leiden, 1735 This list of systems of plant taxonomy presents "taxonomic systems" used in plant classification.
Indeed, three are the atoms in the middle layer (inside the prism); in addition, for the top and bottom layers (on the bases of the prism), the central atom is shared with the adjacent cell, and each of the six atoms at the vertices is shared with other six adjacent cells. So the total number of atoms in the cell is 3 + (1/2)×2 + (1/6)×6×2 = 6.
Homonuclear triatomic molecules contain three of the same kind of atom. That molecule will be an allotrope of that element. Ozone, O 3 is an example of a triatomic molecule with all atoms the same. Triatomic hydrogen, H 3, is unstable and breaks up spontaneously. H 3 +, the trihydrogen cation is stable by itself and is symmetric.
In the rock-salt structure, each of the two atom types forms a separate face-centered cubic lattice, with the two lattices interpenetrating so as to form a 3D checkerboard pattern. The rock-salt structure has octahedral coordination : Each atom's nearest neighbors consist of six atoms of the opposite type, positioned like the six vertices of a ...
The seesaw geometry occurs when a molecule has a steric number of 5, with the central atom being bonded to 4 other atoms and 1 lone pair (AX 4 E 1 in AXE notation). An atom bonded to 5 other atoms (and no lone pairs) forms a trigonal bipyramid with two axial and three equatorial positions, but in the seesaw geometry one of the atoms is replaced ...