A porous membrane has openings scattered on its surface of various size and frequency. This means that such membranes allow various substances to pass through. Any molecules that are larger than the membrane's openings will not pass through.
It means that the plasma membrane lets water through it. A plasma membrane is actually semipermeable, which means that certain molecules can pass through it by diffusion. Other molecules will be too big to pass through the membrane.
Look at the words - "selective" and "permeable".
What does 'selective' mean? You select what to eat - an apple or an orange; you select where to sleep - the bed or the floor; you select what movie to see.
So, selective means to have a choice between things.
Permeable, with respect to membrances, means allowing substances to go through.
In human terms, a DOOR is permeable, but a wall is not. [and technically speaking, sometimes a window is permeable]
So, if a membrane is "selectively permeable" this means that only some things can go in or out through the membrane.
We have many of these membranes in our bodies' cells - membranes that let sodium [Na+] ions in but not calcium [Ca+2] ions.
This is like a rock concert, and only some people have tickets to go in.
It means the substance is able to pass through the membrane.
People live in towns. People are multicellular organisms consisting of trillions of cells. Each cell has a cell membrane.
i would say tha some unexample of plasma membrane would be butts or boobies or maybe even penisis and vaginias ,but thats just my oppinion
If a subsance is applied to a cell that makes the membrane more permeable to ions, the interior voltage changes. If the interior voltage becomes more positive (say from Ð70 mV to Ð60 mV), this is called a depolarization. If the interior voltage becomes more negative (say from Ð70 mV to Ð80 mV) it's called a hyperpolarization.
phospholipids and most proteins to drift about in the plane of the membrane
Visking tubing contains millions of tiny holes which only let small molecules, like water, diffuse through. Large molecules, such as starch, cannot cross the membrane. We say it is partially permeable (permeable means a substance is able to pass through). This is similar to a cell membrane. Visking tubing can therefore be used as a model of a cell.
yes, it is
A selectively permeable membrane is most often attributed to the cell membrane (plasma membrane) of cells. It is constructed of nonpolar phospholipids that will not dissolve many substances, like ions or large molecules. There are carrier proteins embedded in the membrane that allow only certain substances through.
Yes.
People live in towns. People are multicellular organisms consisting of trillions of cells. Each cell has a cell membrane.
it means that any biological membrane allows only certain solute or we can say nutrients that are required by cell, to enter into cell through itself and not other unnecessary particles hrmful to cell.. Such property is called selectively permeable or semi permeable...
plasma membrane is the membrane which surrounds the cells and the other organelle's so if it is non living it will not allow the imp. thing inside and the cells will die,..so i should say it living
i would say tha some unexample of plasma membrane would be butts or boobies or maybe even penisis and vaginias ,but thats just my oppinion
If a subsance is applied to a cell that makes the membrane more permeable to ions, the interior voltage changes. If the interior voltage becomes more positive (say from Ð70 mV to Ð60 mV), this is called a depolarization. If the interior voltage becomes more negative (say from Ð70 mV to Ð80 mV) it's called a hyperpolarization.
i would say tha some unexample of plasma membrane would be butts or boobies or maybe even penisis and vaginias ,but thats just my oppinion
phospholipids and most proteins to drift about in the plane of the membrane
Semi-permeable means that which only allows certain things to pass through. The cell membrane needs to be semi permeable so that it only allows beneficial things (say, ions or water molecules) into the cell whilst keeping harmful things out (eg. toxins and viruses). That's all. Hope this helps you (:
Visking tubing contains millions of tiny holes which only let small molecules, like water, diffuse through. Large molecules, such as starch, cannot cross the membrane. We say it is partially permeable (permeable means a substance is able to pass through). This is similar to a cell membrane. Visking tubing can therefore be used as a model of a cell.