Cellular membrane question

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In summary, during a cellular biology class, it was learned that hydrophilic molecules have difficulty diffusing through the membrane due to its hydrophobic interior. However, water is able to easily diffuse through the membrane even though it is both hydrophilic and hydrophobic. This is because water has "gated" channels that allow it to pass through. This discovery earned the 2003 Nobel prize in chemistry for an M.D., overturning the previous belief of simple diffusion for water passing through the membrane.
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i learned in my cellular biology class today that hydrophillic molecules don't diffuse through the membrane easily, since the inside of the membrane is hydrophobic. my question is that water easily diffuses through the cell membrane, and water isn't just hydrophillic, it is hydro! so why can water diffuse easily through the membrane?[?]
 
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The 2003 Nobel prize in chemistry was acutally given to an M.D. for the discovery of "gated" channels for H2O. For years we thought it was simple diffusion that water passed, but now we have found that there are channels. Quite simple, we should have always known this.

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This is a great question! While water is indeed hydrophilic, it also has unique properties that allow it to easily diffuse through the cell membrane. One key factor is its small size and ability to form hydrogen bonds. These properties allow water molecules to pass through the hydrophobic interior of the membrane by squeezing in between the lipid molecules. Additionally, the membrane contains specialized proteins called aquaporins which act as channels for water to pass through. These proteins are specifically designed to allow water molecules to enter and exit the cell efficiently. So even though water is hydrophilic, its unique properties and the presence of aquaporins in the cell membrane make it easy for water to diffuse through.
 

1. What is the cellular membrane?

The cellular membrane, also known as the cell membrane or plasma membrane, is a thin, semi-permeable barrier that surrounds the cell and separates its internal contents from the external environment. It is composed of lipids, proteins, and carbohydrates, and plays a crucial role in regulating the movement of substances in and out of the cell.

2. How does the cellular membrane maintain its structure?

The cellular membrane is composed of a phospholipid bilayer, meaning it has two layers of phospholipid molecules with their hydrophilic (water-loving) heads facing outward and their hydrophobic (water-fearing) tails facing inward. This structure allows the membrane to maintain its integrity and selectively control the movement of molecules in and out of the cell.

3. What is the function of the cellular membrane?

The cellular membrane has several important functions, including protecting the cell from its surroundings, regulating the movement of substances in and out of the cell, and facilitating communication and interactions with other cells and the environment.

4. How does the cellular membrane control the movement of substances?

The cellular membrane has various mechanisms for controlling the movement of substances, including passive diffusion, facilitated diffusion, and active transport. These processes involve the use of transport proteins and can be influenced by factors such as concentration gradients and membrane potential.

5. Can the cellular membrane repair itself?

Yes, the cellular membrane has the ability to repair itself through a process called endocytosis, where damaged or worn out portions of the membrane are internalized and replaced with new membrane material. This process helps to maintain the structural integrity and functionality of the cellular membrane.

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