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Cell or Plasma Membranes
Every cell has a cell membrane (plasma membrane) that separates the interior of the cell from the outside environment. One of the most important functions of this biological membrane is to protect the cell from outside threats by controlling the movement of substances in and out of the cell.
1,116 Questions
Why plasma membrane cytoplasm and nucleus are common in all animal cell?
That was because of Voldemort, as seen in Harry Potter and the Philosopher's Stone. It was an attempt to destroy Harry Potter, but his magic scar protected him from the attack.
How is water transported across the membrane?
Water is transported by a passive transport called osmosis. Osmosis is diffusion of water across the membrane.
Is phospholipid one of the structured lipid found in cell membranes?
Yes,they are found in plasma membrane.They form the basic structure.
Does biological molecules proteins and lipids have cell membranes?
Proteins and lipids don't have cell membranes but are the molecules that make up the bulk of what a cell membrane is.
Does the cell membrane let sugar water and oxygen enter?
Yes, both are necessary for the cell to produce energy to function.
Is a special type of diffusion that involves moving across a cell membrane?
osmosis is a special type of diffusion that involves water moving across a cell membrane hopefuly this helped :)
What type of barrier are the cell wall and cell membrane?
Well the cell wall is found only in a plant cell while the cell membrane is found in both. The cell wall helps keep the plant in a firm structure. The cell membrane is almost like a gatekeeper however because it lets some particles through that are wanted or need (nutrients etc:) and keeps harmful particles away (wastes ect:)
The biology dictionary describes Cell Wall as "A membrane of the cell that forms external to the cell membrane whose main role is to give cells rigidity, strength and protection against mechanical stress. It is found in cells of plants, bacteria, archaea, fungi, and algae. Animals and most protists do not have cell walls"
The biology dictionary describes a cell membrane as "The cell membrane is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out. It also serves as a base of attachment for the cytoskeleton in some organisms and the cell wall in others. Thus the cell membrane also serves to help support the cell and help maintain its shape. Animal cells, plant cells,prokaryotic cells, and fungal cells have cell membranes."
What the role of protein channels in the cell membrane?
Protein channels are important to facilitate the transport of ions and other larger molecules across the plasma membrane. Large molecules cannot just diffuse thorough the membrane. In addition, polar molecules cannot diffuse through the membrane since it would be energetically unfavorable for them to negotiate the hydrophobic interior of the plasma membrane. Therefore, protein channels are essential in membrane transport.
Could the body survive without bone cells?
There are many organisms that do not have bone cells; these are known as invertebrates. However, if a human being were to have all bone cells removed, then no, such an unfortunate person could not survive. We are not adapted to live as invertebrates. So far there is no way to convert a human being into a living jellyfish, but who knows what future medical research will bring.
What is the layer outside the plant cell membrane?
the layer outside the cell is the Extra Cellular Matrix (ECM). It is composed of glycoproteins, and is used for cell communication and recognition. The ECM lies just outside of the plasmalamela, or cell membrane, which defines the limits of the cell.
How does a plasma membrane determine selectivity of molecules?
Plasma membrane possesses specific protein channels and lipid bilayer. Protein channels are of million different types, each allow a specific molecule to pass through it regarding its size, shape, charges on it, solubility, etc. Fat soluble molecules pass through lipid bilayer.
Do all cell membranes contain the same kind of proteins in the same relative locations?
No. Though all cell membranes have the same general characteristics outlined in any Biology textbook, they are all unique in type of proteins. Cell membranes between members of the same species will differ, and membranes within the same individual with differ also. The location of proteins will differ too, since they are subject to drifting and relocation. Some integral proteins will move slowly or not at all due to their connection to the cytoplasm, but others take advantage of the fluidity of the phospholipid bilayer.
What determines the specific functions of the plasma membrane?
The specific functions of the plasma membrane are determined by its composition of phospholipids, proteins, and cholesterol, which allow it to control the passage of substances in and out of the cell, maintain cell shape, and interact with other cells. Protein channels and carriers embedded within the membrane assist in transporting specific molecules across the membrane, contributing to its functionality.
Why are all living things composed of nucleated cells?
Not all are. Many biologists believe that bacteria are alive, and they do not have a nucleus. Also, though there is some debate, viruses are also sometimes considered alive, and not only do they not have a nucleus, they do not even have a plasma membrane. The definition of what is alive and what is not is quite complex and goes beyond nucleated cells called eucaryotes and non-nucleated cells called procaryotes.
The red blood cells in your body are not nucleated.
