What types of particles are transported using diffusion?
Types of Transport
- Simple diffusion – movement of small or lipophilic molecules (e.g. O2, CO2, etc.)
- Osmosis – movement of water molecules (dependent on solute concentrations)
- Facilitated diffusion – movement of large or charged molecules via membrane proteins (e.g. ions, sucrose, etc.)
What type of molecules pass through simple diffusion?
In simple diffusion, small noncharged molecules or lipid soluble molecules pass between the phospholipids to enter or leave the cell, moving from areas of high concentration to areas of low concentration (they move down their concentration gradient).
What are some molecules that pass through the membrane by diffusion?
3 – Simple Diffusion Across the Cell (Plasma) Membrane: The structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.
What are types of transport proteins?
There are two classes of membrane transport proteins—carriers and channels. Both form continuous protein pathways across the lipid bilayer. Whereas transport by carriers can be either active or passive, solute flow through channel proteins is always passive.
Are transport proteins specific?
Yes. A transport protein is specific for the substance it translocates, allowing only a certain substance to cross the membrane. Aquaporins are channel proteins that facilitate the passage of water molecules through the membrane of certain cells.
How are proteins transported into mitochondria?
Proteins are translocated into the mitochondrial matrix space by passing through the TOM and TIM complexes at sites of adhesion between the outer and inner membranes known as contact sites. Some imported proteins also contain an internal signal sequence that guides their further transport.
What proteins are found in the mitochondria?
|Tim9||YEL020W-A||Complexed with Tim10|
|Tim10||YHR005C-A||Complexed with Tim9|
|Tim12||YBR091C||Associated with Tim22 complex|
|Tim13||YGR181W||Complexed with Tim8|