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Biology-Related Homework Help Cell Biology Topic started by: barry on Feb 9, 2012



Title: Compare and contrast passive and active transport mechanisms, and give an exampl
Post by: barry on Feb 9, 2012
Compare and contrast passive and active transport mechanisms, and give an example of each.


Title: Re: Compare and contrast passive and active transport mechanisms, and give an exampl
Post by: bio_man on Feb 9, 2012
Passive transport involves the movement of molecules across a membrane along the concentration gradient without ATP. Examples of passive transport include simple diffusion, facilitated diffusion, and osmosis. Diffusion is the net movement of particles from regions of greater to lower concentration until equilibrium is reached. Facilitated diffusion is the movement of a substance from higher to lower concentration with aid from a membrane protein. Osmosis is the diffusion of water across a membrane from areas of higher to lower concentrations. Active transport requires the input of energy (ATP) for the movement of solutes typically against the concentration gradient.


Title: Re: Compare and contrast passive and active transport mechanisms, and give an exampl
Post by: Needing help please on Apr 16, 2012
Compare and contrast active transport and passive transport mechanisms?  (Such As)
1 diffusion
2 osmosis
3 endocytosis
4 exocytosis
5 phagocytosis
6 pinocytosis
can anyone help me out please?


Title: Re: Compare and contrast passive and active transport mechanisms, and give an exampl
Post by: ppk on Apr 16, 2012
Active transport requires that the cell uses enegry, or ATP, adenosine triphosphate.

Passive transport requires no energey from the cell as it moves with the concentration gradient.


Title: Re: Compare and contrast passive and active transport mechanisms, and give an exampl
Post by: physioex9need on Apr 16, 2012
Contrasts:

Firstly, the movement of Particles, where Active Transport moves against its concentration gradient, where it can move from a low concentration to a high concentration, such as the transport of Ions and Glucose, whereas Passive Transport moves with its concentration gradient, from a high concentration, to a low concentration to level the concentration, such as the movement of water in Osmosis and the movement of Particles in Diffusion.
Secondly, the mechanisms involved in Active Transport and Passive Transport, as pumps and channels are needed to move specific particles or proteins against the concentration gradient, whereas Passive Transport involves lower mechanisms to move particles across the membrane, as small particles move across the Phospholipids.
Finally, the last contrast is the involvement of ATP in Active Transport, but not in Passive Transport. ATP is a class of Energy and energy is needed more in Active Transport than Passive Transport as particles need to be forced against the concentration gradient. Also the particles will be large and need a "helping hand" during the process of them moving against its concentration gradient.

Comparisons:

Firstly, Active Transport and Passive Transport are both involved within the Phospholipid Bilayer naturally. This is because Active Transport mechanisms, such as protein channels, are embedded with or lie on the Phospholipid Bilayer. Also in Passive Transport, molecules slip within the Phospholipids and out on the other side.
Finally, Active Transport and Passive Transport naturally transport Partilcles across the Phospholipid Bilayer, to supply the cell with its requirements. Active Transport does this by Protein Channels and Vesicles, whereas Passive Transport use methods like Diffusion and Osmosis