Cell Animations

A & P 1

Membrane Receptors

Membrane Receptor - an important concept in human physiology- uses the lock-and-key approach (shape determines function) to allow a molecule of a particular shape to trigger a change in chemical activity

From http://course1.winona.edu/sberg/Free.htm

 

Golgi Apparatus

Golgi Apparatus. This animation shows how material moves through the Golgi system, eventually producing vesicles (perhaps secretion vesicles [SV] heading for the plasma membrane [PM])

From http://course1.winona.edu/sberg/Free.htm

 

Vesicles

From http://course1.winona.edu/sberg/Free.htm

 

Centrosome

Centrosome.  Notice the pair of centrioles at the center and the associated microtubules extending from the centrosome (microtubule organizing center).

From http://course1.winona.edu/sberg/Free.htm

 

Simple Diffusion

Simple diffusion - the red particles are moving from an area of high concentration to areas of lower concentration (in this case, through channels in a membrane)

From http://course1.winona.edu/sberg/Free.htm

 

Carrier-Mediated Passive Transport

Carrier-mediated passive transport = facilitated diffusion

Similar to above model of simple diffusion, except particles move through a carrier mechanism instead of through a simple channel

From http://course1.winona.edu/sberg/Free.htm

 

Active Transport

Active transport - An energy- consuming type of carrier (notice ATP being used) transports molecules (usually to an area of higher concentration - not visible in this animation)

From http://course1.winona.edu/sberg/Free.htm

 

Cotransport

Cotransport (symport) involves more than one type of particle being transported by in the same direction at the same time by the same mechanism

From http://course1.winona.edu/sberg/Free.htm

 

Sodium-potassium Pump

The sodium-potassium pump (Na+-K+ ATPase) is an example of countertransport in which two kinds of particles are transported at the same time in opposite directions by the same mechanism.

The Na+-K+ pump is present in all cells and is an important part of mechanisms that we'll discuss later. 

From http://course1.winona.edu/sberg/Free.htm

 

Endocytosis

Endocytosis is a kind of bulk transport where large amounts of material are brought into a cell.  Notice the role of receptors in identifying what is "good to eat" and that membrane is removed from the plasma membrane.

From http://course1.winona.edu/sberg/Free.htm

 

Exocytosis

Exocytosis is a kind of bulk transport in which large amounts of material are moved out of a cell.  Notice also that new membrane is added to the plasma membrane (from the secretion vesicle)

From http://course1.winona.edu/sberg/Free.htm