cell membrane

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membrane

 [mem´brān]
a thin layer of tissue that covers a surface, lines a cavity, or divides a space or organ. adj., adj mem´branous.
alveolar-capillary membrane (alveolocapillary membrane) a thin tissue barrier through which gases are exchanged between the alveolar air and the blood in the pulmonary capillaries. Called also blood-air barrier and blood-gas barrier.
alveolodental membrane periodontium.
arachnoid membrane arachnoid.
basement membrane a sheet of amorphous extracellular material upon which the basal surfaces of epithelial cells rest; it is also associated with muscle cells, Schwann cells, fat cells, and capillaries, interposed between the cellular elements and the underlying connective tissue. It comprises two layers, the basal lamina and the reticular lamina, and is composed of Type IV collagen (which is unique to basement membranes), laminin, fibronectin, and heparan sulfate proteoglycans.
basilar membrane the lower boundary of the scala media of the ear.
Bowman's membrane a thin layer of basement membrane between the outer layer of stratified epithelium and the substantia propria of the cornea.
Bruch's membrane the inner layer of the choroid, separating it from the pigmented layer of the retina.
cell membrane plasma membrane.
decidual m's (deciduous m's) decidua.
Descemet's membrane the posterior lining membrane of the cornea; it is a thin hyaline membrane between the substantia propria and the endothelial layer of the cornea.
diphtheritic membrane the peculiar false membrane characteristic of diphtheria, formed by coagulation necrosis.
drum membrane tympanic membrane.
epiretinal membrane a pathologic membrane partially covering the surface of the retina, probably originating chiefly from the retinal pigment epithelial and glial cells; membranes peripheral to the macula are generally asymptomatic, while those involving the macula or adjacent to it may cause reduction in vision, visual distortion, and diplopia.
extraembryonic m's those that protect the embryo or fetus and provide for its nutrition, respiration, and excretion; the yolk sac (umbilical vesicle), allantois, amnion, chorion, decidua, and placenta. Called also fetal membranes.
false membrane a membranous exudate, such as the diphtheritic membrane; called also neomembrane.
fenestrated membrane one of the perforated elastic sheets of the tunica intima and tunica media of arteries.
hemodialyzer membrane the semipermeable membrane that filters the blood in a hemodialyzer, commonly made of cuprophane, cellulose acetate, polyacrylonitrile, polymethyl methacrylate, or polysulfone.
Henle's membrane fenestrated membrane.
high efficiency membrane a hemodialyzer membrane that has clearance characteristics that increase progressively with increases in dialysis blood flow rates; this usually implies that the membrane is not a high flux membrane.
high flux membrane a hemodialyzer membrane that has a high permeability to fluids and solutes and thus a high rate of clearance of fluids and solutes composed of large molecules.
hyaline membrane
1. a membrane between the outer root sheath and inner fibrous layer of a hair follicle.
3. a homogeneous eosinophilic membrane lining alveolar ducts and alveoli, frequently found at autopsy of infants that were preterm. See also hyaline membrane disease.
hyoglossal membrane a fibrous lamina connecting the undersurface of the tongue with the hyoid bone.
impaired oral mucous membrane a nursing diagnosis approved by the North American Nursing Diagnosis Association, defined as disruptions of the lips and soft tissue of the oral cavity. Changes in the integrity and health of the oral mucous membrane can occur as a characteristic of such medical disorders as periodontal disease, uncontrolled diabetes mellitus, oral cancer, and infection with herpes. Chemical irritants such as alcohol and tobacco can also adversely affect the oral mucous membrane, as can mechanical trauma due to broken teeth, poorly fitting dentures, and endotracheal intubation. Other etiologic factors include dehydration, mouth breathing, poor oral hygiene, radiation to the head or neck, and antineoplastic agents.

Preventive measures that can help maintain the health and integrity of the oral mucosa will depend on the cause. Routinely brushing and flossing the teeth during the day and at bedtime can help avoid dental caries and periodontal disease. Some patients may need instruction in the proper procedure for cleaning the teeth and removing debris and plaque, or they may need assistance in devising ways to cope with physical disabilities that make good oral hygiene difficult for them. Patients who are unconscious or unable to perform self-care activities should have mouth care as often as needed to keep the mouth clean and moist and avoid aspiration of debris and infectious microorganisms. Adequate hydration and a lip lubricant can help avoid alterations in the oral mucosa and promote comfort.
limiting membrane one that constitutes the border of some tissue or structure.
mucous membrane the membrane covered with epithelium that lines the tubular organs of the body.
Nasmyth's membrane primary cuticle.
nuclear membrane
1. either of the membranes, inner and outer, comprising the nuclear envelope.
olfactory membrane the olfactory portion of the mucous membrane lining the nasal fossa.
placental membrane the membrane that separates the fetal from the maternal blood in the placenta.
plasma membrane the membrane that encloses a cell; it is composed of phospholipids, glycolipids, cholesterol, and proteins. The primary structure is a lipid bilayer. Phospholipid molecules have an electrically charged “head” that attracts water and a hydrocarbon “tail” that repels water; they line up side by side in two opposing layers with their heads on the inner or outer surface of the membrane and their tails in the core, from which water is excluded. The other lipids affect the structural properties of the membrane. Proteins embedded in the membrane transport specific molecules across the membrane, act as hormone receptors, or perform other functions.
Reissner's membrane the thin anterior wall of the cochlear duct, separating it from the scala vestibuli.
membrane of round window secondary tympanic membrane.
Scarpa's membrane tympanic membrane, secondary.
semipermeable membrane one permitting passage through it of some but not all substances.
serous membrane the membrane lining the walls of the body cavities and enclosing the contained organs; it consists of mesothelium lying upon a connective tissue layer and it secretes a watery fluid.
synovial membrane the inner of the two layers of the articular capsule of a synovial joint; composed of loose connective tissue and having a free smooth surface that lines the joint cavity.
tympanic membrane see tympanic membrane.
tympanic membrane, secondary the membrane enclosing the round window; called also Scarpa's membrane.
unit membrane the trilaminar structure of all cellular membranes (such as the plasma membrane, nuclear membranes, mitochondrial membranes, endoplasmic reticulum, lysosomes) as they appear in electron micrographs. The biochemical structure is a lipid bilayer.
virginal membrane hymen.
vitelline membrane the external envelope of an ovum.
vitreous membrane
2. hyaline membrane (def. 1).
4. a delicate boundary layer investing the vitreous body.

cell mem·brane

the protoplasmic boundary of all cells that controls permeability and may serve other functions through surface specializations, for example, active ion transport absorption by formation of pinocytotic vesicles or receptor-mediated antigen recognition; its fine structure is trilaminar and consists of the electron-dense lamina externa and lamina interna with an electron-lucent lamina intermedia.

cell membrane

n.
The semipermeable membrane that encloses the cytoplasm of a cell. Also called cytomembrane, plasmalemma, plasma membrane.

cell mem·brane

(sel mem'brān)
The protoplasmic boundary of all cells that controls permeability and may serve other functions through surface specializations (e.g., active ion transport, absorption by formation of pinocytotic vesicles, and antigen recognition). Its fine structure is trilaminar and consists of the electron-dense lamina externa and lamina interna with an electron-lucent lamina intermedia.
Synonym(s): plasma membrane, plasmalemma, Wachendorf membrane (2) .

cell membrane

or

plasma membrane

the outer boundary of cells, the structure of which is visible only under the ELECTRON MICROSCOPE and which is still not clearly understood. Two major models have been proposed for membrane structure: the UNIT MEMBRANE MODEL (now outdated) and the FLUID-MOSAIC MODEL structures. The cell membrane gives shape and some protection to the cell, and also acts as a regulatory filter for transport of materials in and out of the cell (see ACTIVE TRANSPORT, DIFFUSION). Higher plants, fungi and most bacteria have a CELL WALL outside the cell membrane.

Wachendorf,

Eberhard J., German botanist and anatomist, 1702-1758.
Wachendorf membrane - the protoplasmic boundary of all cells that controls permeability and may serve other functions through surface specializations. Synonym(s): cell membrane; pupillary membrane

cell mem·brane

(sel mem'brān)
The protoplasmic boundary of all cells that controls permeability and may serve other functions through surface specializations.
Synonym(s): plasma membrane, plasmalemma, Wachendorf membrane (2) .
References in periodicals archive ?
Meanwhile, AsA treatment protected seeds cellular structure against damage of ROS, as presented that cytoplasmic membrane, nuclear membrane, mitochondria and cristae were all normal and complete (Fig.
The most important function of cytoplasmic membrane of bacteria is to form a permeable barrier, regulating the passage of solutes between the cell and the outer environment.
Keywords: Escherichia coli, outer membrane, cytoplasmic membrane, periplasmic space, nucleoid, ribosomes, vesicles, aberrant mesosomes, betaine
The host cell looses the ability to synthesize protein, RNA and DNA and can no longer respire exogenous substrates and its cytoplasmic membrane becomes permeable to small molecules.
A synthetic peptide derived from human lactoferricinhas been found to be effective indepolarizing the bacterial cytoplasmic membrane with a loss of pH gradient [107].
So, release of APh is related with damage of alkaline border and cytoplasmic membrane of tubular epithelium of proximal channels.
Freeze-drying causes damages in cytoplasmic membrane of PseudomonasfluorescensBTP1 as shown by increased electrical conductivity and cytometric analysis.
Unlike the beta-lactams and quinolones, which utilize porin channels to cross the outer membrane to get to their target, the aminoglycosides bind to the lipopolysaccharide (LPS) on the outer membrane surface, increasing the permeability of the membrane so that the aminoglycoside can get to the cytoplasmic membrane. OprH is an outer membrane protein that protects LPS from being bound by the aminoglycosides.

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