Cell Menbrane

Fluid Mosaic Model

A mixed composition or a mosaic of phospholipids, glycolipids, sterols and proteins.

Transport Proteins

Passively let specific solutes diffuse through a menbrene-spanning channel in their interior or actively pump them through.

Recetor Proteins

Are designed so special molecules can bind to them, and send messages to the cell that trigger some sort of reaction within the cell.

Recognition Proteins

Indentify the type of substances that enter the cell.




Adhesion Proteins

Join cells to form a tissue.

Comunication Proteins

Comunicate a cell to another






Diffusion

The process by which molecules spread from areas of high concentratiion, to areas of low concentration. When the molecules are even throughout a space

Electric Gradient


Is a spatial variation of both electrical potential and chemical concentration across a membrane.



Pressure Gradient

 Is a physical quantity that describes in which direction and at what rate the pressure changes the most rapidly around a particular location.




Osmosis

 Is the movement of solvent molecules through a selectively-permeable membrane into a region of higher solute concentration, aiming to equalize the solute concentrations on the two sides.

Hypotonic Solution

 Is the same as the solute concentration of another solution with which it is compared.

Hypertonic Solution

 Is a solution having a lesser solute concentration than the cytosol.

Isotonic Solution

Solutions that have equal osmotic pressure, such as the isotonic environment.

Hydrostatic Pressure

 Is the pressure exerted by a fluid at equilibrium due to the force of gravity.




Osmotic Pressure

Is the pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane.

Endocytosis

A small patch of plasma menbrane balloons inward and pinchesoff inside the cytoplasm.

Exocytosis

A vesicle moves to the cell surface, and then the protein-studded lipid bilayer of  its menbrane.

Phagocytosis

("cell eating")   

Cell Structure and Funtion

Nucleoid


 Region of the cytoplasm that is not enclosed in a menbraneous sac

Lipid bilayer


 Is a continuous, oily boundary that prevent the free passage of water-soluble substances.

Wavelength


 Is the distance from the peak of one wave to the peak behind.

Electron microscope

 Use magnetic lense to bend and diffract beams of electron.

Transmittion electron microscope


Pass throught an specimen  and is use to make images of internal details.


Scanning electron microscope


A beam of electron back and forth across a surface of the specimen, which has been given a thin metal coating.


Organelles


Start out life with a nucleus and other menbrane.


Secretory Pathway


Polypeptide chains from some ribosomes, through ER , and Golgi bodies and out of the cell.


Endocytic pathway


Move  ions and molecules into cytoplasm.


Vesicles


Tiny sacs.


Nuclear envelope


Is a double menbrane in which two lipids bilayers are pressed against each other.


Nucleolus


Is a non-membrane bound structure composed of proteins and nucleic acids found within the nucleus.


Chromatic


Cell collection and all proteins associated with it. 


Peroxisomes


Are organellesfound in virtually all eukaryotic cells. They are involved in the catabolism ofvery long chain fatty acids, branche chain fatty acids D-amino acids polyamines, and biosynthesis of plasmalogens.


Cell Junctions


Are mollecular structure whre cell send and receives signals or materials or recognizes and glues itself to alls.


Basal Body


Is an organelleformed from a centriole, and a short cylindrical array of microtubules


Pseudopods


False feet.