Why does the permeability increase when the carrier on the membrane does not work after cell death?

After cell death, the permeability of the membrane increases, not because of the carrier, but because the phospholipid bilayer loses its continuous structure.

Cells die, and the phospholipid bilayer ruptures and loses integrity. As a result, permeability increases, and it is almost completely permeable.

The permeability of the cell is determined by the structure of the phospholipid bilayer, and after the cell dies, the cell membrane becomes loose, and the fluidity of phospholipids weakens, resulting in a random membrane gap that becomes larger, so the permeability increases.

Water is communicated through the water molecule channel on the cell membrane, and after the cell dies, the water molecule channel is no longer controlled by the cell, and due to its own tension, this channel will continue to increase, which causes the total permeability of the dead cell.

The cell membrane is a barrier that prevents extracellular substances from entering the cell freely, which ensures the relative stability of the intracellular environment and enables various biochemical reactions to run in an orderly manner. Its most important property is semi-permeability, or selective permeability, which has a strong selective permeability to substances entering and exiting the cell. Therefore, only some small molecules of sugars, inorganic salts, lipids and some proteins can be allowed to pass through.

Macromolecular proteins need to rely on carriers, and after cell death, the cell membrane loses its semi-permeability, and the substances inside and outside the cell can naturally flow unimpeded. Just like the two sides of the river can only be transported by boats, but after the river dries up, even if there is no ship, the goods on both sides of the river can flow smoothly.

The cell death membrane becomes fully permeable and non-selectively permeable, which is equivalent to no membrane.

Apoptosis. It refers to the autonomous and orderly death of cells controlled by genes in order to maintain the stability of the internal improvement environment. (also known as procedural death).

Normal cells are transformed from senescent cells to apoptosis, and the characteristics of decaying cells are that the cells undergo significant changes in morphology, cell shrinkage, plasma membrane permeability and fragility are improved, and mitochondria.

The number is reduced, chromatin is solidified, broken, etc.

From this, it can be concluded that the permeability of apoptotic cells is also improved, because the proteins in senescent cells undergo a series of changes that make the cell membrane.

The recognition of carrier proteins on is reduced, resulting in greater permeability. Parsley.

Hope that helps

During apoptosis, the permeability of the cell membrane will not increase, and vesicles will form on the cell membrane in the early stage, but the cell membrane structure will not change. Apoptotic bodies form in late stages.

Reduced cell membrane permeability, resulting in a decrease in the rate of transmembrane transport of substances.

During cell senescence, the fragility of the cell membrane increases, the selective permeability decreases, and the type, number and sensitivity of membrane receptors to ligands change, so that the material transport function is reduced.

The life course of a cell goes through several stages: undifferentiated, differentiated, growing, maturing, aging, and dying. The senescent and dead cells are removed by the body's immune system, and new cells are constantly generated from the corresponding tissues and organs to make up for the aging and dead cells. The dynamic balance between cell senescence and death and the growth of new cells is the basis for maintaining the normal life activities of the body.

Cellular senescence and senescence are two different concepts, but they are closely related. Aging is based on the aging of the cells that make up the body at the level of the whole, system, or organ, but it does not mean that all the cells that make up the body have senesced. Cell senescence and death and the growth and replacement of new cells in normal life activities are the inevitable laws of metabolism, which also avoids the degeneration of tissue structure and the accumulation of senescent cells, so that the body delays the overall aging.

The lifespan and renewal time of different types of cells vary greatly, such as the lifespan of mature granulocytes is only more than 10 hours, the lifespan of red blood cells is about 4 months, the epithelial cells of the gastrointestinal tract need to be renewed once a week, the renewal of pancreatic epithelial cells takes about 50 days, and the renewal of epidermal cells takes about 1 2 months.

Generally speaking, the carrier on the cell membrane refers to the carrier protein, which is involved in both passive and active material transport. Passive material transport by carrier proteins does not require ATP for energy. As for the other types, I haven't heard of them, so I'll see if anyone adds them.

Carriers are also called transporter membrane proteins. are membrane proteins present on the membrane and involved in assisting diffusion and active transport.

It can be roughly divided into two categories: 1. Carrier proteins: such as carriers for transporting glucose, sodium-potassium pumps, calcium pumps, proton pumps, etc.

2. Channel proteins, which are further divided into potential gate channels and ligand gate channels. Such as sodium ion channel, potassium ion channel, etc.

It is the ease with which a substance passes through a biosemipermeable membrane.

It should be enlarged. The permeability function of the cell membrane is changed, which reduces the material transport function, which is manifested in:

1. Do not keep out harmful substances, so that harmful substances can enter and harm cells.

2. Extravasation of useful ions in the cell;

3. Unable to maintain normal intracellular and extracellular osmotic pressure;

4. The permeability of the selection is reduced, and the substances to be absorbed cannot be selected normally.

Enhanced. Because of cellular senescence, some carrier proteins and channel proteins are shed, and the ability to control the entry and exit of substances will be weakened, that is, the permeability will be enhanced.

Enhanced, the function of the cell membrane is weakened, which cannot prevent the entry and exit of some substances.

No, for example, some heavy metal ions, the cell does not need it, and the cell membrane does not let it choose to pass through. Neither the carrier nor the carrier can be passed. Unless the structure of the membrane is damaged, the permeability is changed, and the cell membrane loses its selective permeability.

No, the lack of permeability to an ion means that there are no carrier proteins on the cell membrane.

There is a phenomenon that can prove that the cell membrane of living cells is selectively permeable, and the entry and exit of substances are restricted, while the dead cells are free to enter and exit anything, which does not mean that the permeability of the aging cell membrane increases, because aging is a process from birth to death.

In senescent cells, the permeability of the cell membrane increases.

Animal cell senescence is characterized by the following aspects:

1. Enlargement of the nucleus and chromosome consolidation in the nuclear envelope;

2 Moisture reduction ;

3. The fluidity of the cell membrane decreases and the permeability increases;

4. Decreased enzyme activity;

5 Mitochondria, endoplasmic reticulum, etc. also have corresponding changes.