enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Crystal structure - Wikipedia

    en.wikipedia.org/wiki/Crystal_structure

    Crystal structure of table salt (sodium in purple, chlorine in green) In crystallography, crystal structure is a description of ordered arrangement of atoms, ions, or molecules in a crystalline material. [1] Ordered structures occur from intrinsic nature of constituent particles to form symmetric patterns that repeat along the principal ...

  3. Cell membrane - Wikipedia

    en.wikipedia.org/wiki/Cell_membrane

    Another example of a transmembrane protein is a cell-surface receptor, which allow cell signaling molecules to communicate between cells. [31] 3. Endocytosis: Endocytosis is the process in which cells absorb molecules by engulfing them. The plasma membrane creates a small deformation inward, called an invagination, in which the substance to be ...

  4. Nuclear envelope - Wikipedia

    en.wikipedia.org/wiki/Nuclear_envelope

    Nuclear envelope. The nuclear envelope, also known as the nuclear membrane, [1][a] is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membranes: an inner nuclear membrane and an outer nuclear membrane. [4]

  5. Lipid bilayer - Wikipedia

    en.wikipedia.org/wiki/Lipid_bilayer

    The three main structures phospholipids form in solution; the liposome (a closed bilayer), the micelle and the bilayer. The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells.

  6. Cubic crystal system - Wikipedia

    en.wikipedia.org/wiki/Cubic_crystal_system

    A network model of a primitive cubic system. The primitive and cubic close-packed (also known as face-centered cubic) unit cells. In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals.

  7. Crystallization - Wikipedia

    en.wikipedia.org/wiki/Crystallization

    Crystallization occurs in two major steps. The first is nucleation, the appearance of a crystalline phase from either a supercooled liquid or a supersaturated solvent. The second step is known as crystal growth, which is the increase in the size of particles and leads to a crystal state. An important feature of this step is that loose particles ...

  8. Atomic packing factor - Wikipedia

    en.wikipedia.org/wiki/Atomic_packing_factor

    where N particle is the number of particles in the unit cell, V particle is the volume of each particle, and V unit cell is the volume occupied by the unit cell. It can be proven mathematically that for one-component structures, the most dense arrangement of atoms has an APF of about 0.74 (see Kepler conjecture), obtained by the close-packed ...

  9. Biomolecular structure - Wikipedia

    en.wikipedia.org/wiki/Biomolecular_structure

    Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule of protein, DNA, or RNA, and that is important to its function.The structure of these molecules may be considered at any of several length scales ranging from the level of individual atoms to the relationships among entire protein subunits.