The function of the cell membrane, what are the three major functions of the cell membrane?

Main function of cell membrane: The cell membrane is essential for the integrity of the entire structure of the cell and for the normal life activities of the cell. Its functions can be summarized in the following aspects.

1) The boundary membrane of the cell, which is the most important function of the cell membrane. Whether it is a eukaryotic cell or a prokaryotic cell, there must be a boundary membrane formed by a certain membrane structure, otherwise there would be no cells. The appearance of the cell membrane allows life to originate into the form of the cell, and also ensures the normal progress of the cell's vital activities.

The emergence of cell membranes concentrates various biological macromolecules into a relatively stable microenvironment, which is conducive to the material and energy metabolism of cells, as well as the growth and development of cells. (2) The existence of the transmembrane transport membrane of matter makes the cell a relatively independent system, but the cell is not a closed system, and the survival, growth and development of the cell depend on the exchange of substances inside and outside the cell. Membranes are selective for the transport of substances and only operate when they are needed.

Substances can be transported from the side with high concentrations to the side with low concentrations, and from the side with low concentrations to the side with high concentrations. The former is passive transport and does not require cells to provide metabolic energy; The latter is an active transport that requires cells to provide metabolic energy. For the transport of macromolecules, cells adopt the mode of endocytosis and efflux, and transport the material by encapsulating it in vesicles.

3) Some proteins on the signal transduction membrane belong to signal receptor proteins, which bind to extracellular signaling molecules to be activated, and then transfer the signal into the cell, and then pass along the signaling pathway through the intracellular signal transduction molecules, and finally produce specific biological effects. For example, certain signaling molecules can promote cell proliferation when they activate receptors on cell membranes. (4) Intercellular connections and communicationIn multicellular organisms, cells carry out a variety of cell-to-cell interactions through cell membranes.

There are many ways to connect between animal cells, which can be summarized as: tight connection, anchor connection and gap connection, and plant cells are mainly connected together by cell walls. Some cell junctions mainly provide a structural basis for cell-to-cell communication, such as intergap junctions in animal cells, which form pore structures between adjacent cells; The plasmodesmata between plant cells also becomes a channel for material transport and information exchange between cells.

5) Intercellular recognition, recognition refers to the cell's recognition and identification of the same or different cells, homologous or heterologous cells, as well as its own or different molecules. Signal transmission is achieved through the selective interaction of cell surface receptors with extracellular signaling molecules, resulting in a series of physiological and biochemical reactions. Cell recognition is a very important part of cell development and differentiation, and cells form different types of tissues by recognition and adhesion.

Protect, control the entry and exit of substances.

The three main functions of the cell membrane are:1. Secretion function.

2. Excretion function.

3. Immune deficiency function.

Overview:

The cell membrane encloses the cell, so that the cell can maintain relative stability and maintain normal life activities. In addition, the absorption of nutrients necessary for cells and the excretion of metabolites pass through the fine grandchild membrane. Therefore, this selective property of the cell membrane that allows certain molecules to enter or exit the cell is called selective permeability.

This is one of the most basic functions of the cell membrane. If the cell loses this function, the cell dies.

The functional property of the cell membrane is selective permeability. This is because the cell membrane is mainly an elastic semi-permeable membrane composed of phospholipids. Cell membranes are mainly composed of lipids (mainly phospholipids), proteins, and sugars. Among them, proteins and lipids are the main ones.

In addition to this, there are three aspects of the function of the cell membrane:

1. Separate the cell from the external environment, 2. Control the entry and exit of substances into and out of the cell, 3. Carry out information exchange between cells.

The function of the cell membrane is threefold:

1. Separate the cells from the external environment;

2. Control the entry and exit of substances into and out of cells;

3. Carry out information exchange between cells.

The functional property of the cell membrane is selective permeability.

Its most important property is semi-permeability, or selective permeability, which has a strong selective permeability to substances entering and exiting the cell. The cell membrane and the intracellular membrane system are collectively referred to as biomembranes and share the same basic structural characteristics.

Every cell has a layer of cell membrane outside it, so what is the function of the cell membrane?

The functional wheel of the cell membrane is highThe functions of the cell membrane are: separating and forming cells and organelles, providing a relatively stable internal environment for the life activities of the cell, and the area of the membrane is greatly increased, which improves the biological functions that occur on the membrane; barrier effect, water-soluble substances on both sides of the membrane can not pass freely; selective transport of matter, accompanied by the transfer of energy; Biological functions: hormone action, enzymatic reaction, cell recognition, electron transmission, etc.; recognition and transmission of information functions (mainly relying on glycoproteins); Substance transport function:

The exchange of substances between the cell and its surroundings is achieved through the transport function of the cell membrane.

Components of cell membranesThe cell membrane, also known as the cytoplasmic membrane, is a thin film on the surface of the lead Chang cell, the thickness of the cell membrane is about 7-8nm, the chemical composition of the cell membrane is basically the same, mainly composed of lipids, proteins and sugars, the content of each component is about %-10%, of which the main components of lipids are phospholipids and cholesterol, in addition, the cell membrane also contains a small amount of water, inorganic salts and metal ions.