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Found Membrane 244 times.

Displaying results 1 to 10.

1. 12-O-tetradecanoylphorbol-13-acetate (TPA)
A plant phorbol ester which promotes tumor formation by activating membrane protein kinase C.

2. Abrin (agglutinin, toxalbumin)
A highly poisonous protein found in the seeds of Abrus precatorius, the rosary pea. Abrin is toxic because it inhibits protein synthesis, causing symptoms such as internal bleeding, intestinal upset, and the irritation of mucous membranes. It was formerly used to treat some chronic eye disorders and it is currently being researched as a potential chemotherapy drug.

3. Acetylcholine
A chemical released at neuromuscular junctions that binds to receptors on the surface of the plasma membrane of muscle cells, causing an electrical impulse to be transmitted. The impulse ultimately leads to muscle contraction.

4. Acrosome
A membrane-bound section at the tip of the head of a sperm which contains lytic enzyme s (hyaluronidase in mammalian sperm) which break down the outer coat of the egg and allow the sperm to inject its haploid DNA .

5. Acrosome
Anterior membrane-bound compartment covering the sperm head that contains lytic enzyme s, which help the sperm digest through the tough outer surface of the egg . The compartment is secreted by the Golgi apparatus of the spermatid (young sperm cell).

6. Action potential (nerve impulse)
The sequential, electrochemical polarization and depolarization that travels across the membrane of a nerve cell (neuron) in response to stimulation (touch, pain, cold, etc.)

7. Action potential
A reversal of the electrical potential in the plasma membrane of a neuron that occurs when a nerve cell is stimulated; caused by rapid changes in membrane permeability to sodium and potassium.

8. Active transport
Transport of molecules against a concentration gradient (from regions of low concentration to regions of high concentration) with the aid of proteins in the cell membrane and energy from ATP .

9. Amebiasis (amebic dysentery)
Amebiasis is an infection with amoebas (a type of protozoan), particularly Entamoeba histolytica. The disease is contracted by eating food or drinking water that has been infected with encysted forms of the amoebas. The symptoms include diarrhea, weakness, and sometimes jaundice. During the course of the disease, sores and abscesses form on the mucous membrane of the large intestine (sometimes causing perforations), and the abscesses may be carried to the liver via the portal vein. Patients are usually treated with drugs called metronidazole (Flagyl) and chloroquinine; they may need to be medicated for up to three months to clear the infection.

10. Anisotropic membrane
This type of synthetic membrane has an asymmetric pore structure: a thin film with tight pores backed by a thicker film with wider pores. This type of membrane is used for ultrafiltration and reverse osmosis ; the porous side faces the feed stream and the tight-pored side faces the product stream.

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