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The process where a nonpolar molecule can just passively get across a membrane is called?
Wiki User
∙ 14y ago
facilitated diffusion
Wiki User
∙ 12y ago
Wiki User
∙ 14y agodiffusion
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What process moves water out of a cell?
Osmosis. It's a type of facilitated diffusion in cells because a water molecule is too large to passively diffuse across a plasma membrane. You need to set it on fire first.
Why did detergent disrupt the bacterial cell membrane but not destry our skin cell?
I guess that is because bacterial membrane has different phospholipids, phospatidyl ethanolamine while we have phosphatidyl choline. I don't think all detergent can disrupt the bacterial membrane, but antibacterial soap.
What is diffusion in biology?
Diffusion is the process that occurs when a certain concentrated volume of material moves to a less concentrated state. Facilitated diffusion is different and is done with the help of pumps actively transporting materials across the cell membrane to create the equilibrium on both sides of the membrane. ža specific type of passive transport žthe movement of particles from an area of high concentration to an area of low concentration ždissolved particles that are small or nonpolar can diffuse through the cell membrane ždiffusion is used to reach equilibrium –equilibrium: a condition in which the concentration of a substance is equal throughout a space
When a cell will engulf a large food molecule to take it in?
This would be called phagocytosis. Pseudopodia would extend out from the cell and sorround the large foreign particle, thereby engulfing it in its own membrane. This membrane would break off and re-connect together, leaving the particle in a membrane, able to then have enzymes injected to dissolve it for varoius purposes depending on what it is.
What is the need for a semi permeable membrane?
we need a semipermeable membrane for a process called osmosis...
When hydrostatic pressure forces water across a membrane passively the process is called?
It's called Filtration
What process moves water out of a cell?
Osmosis. It's a type of facilitated diffusion in cells because a water molecule is too large to passively diffuse across a plasma membrane. You need to set it on fire first.
How would a polar molecule like water travel through the plasma membrane?
The structure of cell membrane allows nonpolar molecules to diffuse, but not polar molecules. Membrane architecture is in the form of a phospholipid bilayer. A single phospholipid has a "head" composed of a polar NH3 group, and two "tails" composed of nonpolar fatty acids. The lipids spontaneously arrange themselves into bilayers with the hydrophilic heads directed outward, and the hydrophobic tails facing inward. Because nonpolar solvents can only dissolve nonpolar solutes, polar molecules cannot mix with the nonpolar inside of the lipid bilayer. A polar molecule cannot cross the cell's lipid membrane without aid from a carrier protein. While this is true, there are multiple forces that dictate whether or not a molecule can cross a phospholipid membrane, including electrochemical gradients and size. Very small and non-polar molecules have a very easy time crossing the phospholipid bilayer. However, very small, polar molecules like water can also cross the phospholipid bilayer due to hydrostatic pressure and concentration gradient differences. Water will, but with some difficulty because of it's polarity. Aquaporins, protein channels embedded into cellular membranes allow for sufficient amounts of water to diffuse into cells.
What process requires energy to bring molecule across the cell membrane?
active transport
In which process does a portion of the cell membrane fold inward and surround molecule to bring them into the cell?
ENDOCYTOSIS
What is the process by which substances are moved through the cell membrane by a carrier molecule?
facilitated diffusion or active transport
When molecule cause cell membrane to bulge inward forming a vesicle it is undergoings?
This process is called endocytosis.
What is the process called when molecules must join with another molecule such as a protein to get through a membrane?
facilitated diffusion
What is it called when a part of a cell membrane closes around a molecule to allow the molecule to enter the cell?
This is called endocytosis.
A small polar molecule enters a cell with help from a membrane protein. No additional energy was needed to complete this process. What type of transport is this?
Facilitated
How can cells stop diffusion through protein channels?
Well there are many different factors that might dictate whether or not a molecule is capable of passively (diffusion) crossing the threshold of the phosolipid bi-layer (cell membrane). The size would be one variable. If it is too large, it might require assistance to cross over. The polarity of the molecule as it might interact negatively (no pun intended) with the polarity of either the cell membrane or the cell entirely, if it contains large amounts of opposing ions. And then, of course, the concentration gradient of the molecule and how much of this same molecule exists in and outside the cell itself. If any of these obstacles exists, the molecule would require active transport into the cell, which means it would require the expenditure of energy, or a pump or gateway of some kind, depending on the substance...
Why did detergent disrupt the bacterial cell membrane but not destry our skin cell?
I guess that is because bacterial membrane has different phospholipids, phospatidyl ethanolamine while we have phosphatidyl choline. I don't think all detergent can disrupt the bacterial membrane, but antibacterial soap.
