What is the physiological significance of how the cell membrane actively transports Na and K against

Na+-K+-ATP pump on the membrane, energy dissipation (ATP), usually 1ATP is transferred out of 3Na+ (phosphorylation at this time) and transferred to 2K+ (dephosphorylation at this time).

It can maintain the osmotic pressure of cells to maintain cell morphology;

formation of resting potentials (associated with nerve excitation);

Formation of potential energy reserves (associated with synergy).

Maintain K and maintain normal life activities of cells.

What is the physiological significance of Na+-K+ pump activity?

Active transportation. The characteristics are: inverse concentration gradient (inverse chemical gradient) transport; Energy is required; Both have carrier proteins.

The energy required for active transport** mainly includes: ionic gradient dynamics in cooperative transport; ATP-driven pumps obtain energy by hydrolyzing ATP; Light-driven pumps use light energy to transport substances, which are found in bacteria.

Na+--K+ pump composition: a tetramer composed of 2 large subunits and 2 small subunits, which is actually Na+-K+ ATPase.

Distributed in animal cells.

of the plasma membrane. How the Na+--K+ pump works:

1) Na+-K+ ATPase undergoes a conformational change through phosphorylation and dephosphorylation processes, resulting in affinity with Na+, K+.

There are changes. 2) Na+ binds to the enzyme on the inner side of the membrane, activates the activity of ATPase, decomposes ATP, the enzyme is phosphorylated, the conformation changes, and the site of binding to Na+ turns to the outside of the membrane; This phosphorylated enzyme has a low affinity for Na+ and a high affinity for K+, thus releasing Na+ on the outside of the membrane and binding to K+.

3) After K+ binds to phosphorylase, the enzyme is dephosphorylated, and the conformation of the enzyme returns to its original state, so the part where the hail ruler binds to K+ turns to the inner side of the membrane, and the affinity between K+ and the enzyme decreases, so that K+ is released in the membrane and binds to Na+.

4) Each cycle consumes one ATP; Three Na+ are transferred out and two K+ are transferred

The role of Na+-K+ pump: maintain the permeability of the cell and maintain the volume of the cell; Maintain an intracellular environment with low Na+ and high K+; Maintain the resting potential of fine source high cells.

Cell membrane structure and material transport function(1)Liquid mosaic model of membrane structure: In the process of cell metabolism, it is necessary to continuously and selectively ingest and excrete certain substances through the cell membrane. Cell membranes and organelle membranes are mainly composed of lipids and proteins.

According to the liquid mosaic model of the membrane structure, it is believed that the membrane is based on the lipid bilayer in the liquid state of the elder mu, and many proteins with different structures and functions are embedded in it.

2) Substance transport function of cell membrane: The transmembrane transport pathways of substances are:

Diffusion alone: The direction and speed of diffusion depends on the difference in concentration of the substance on both sides of the membrane and the permeability of the membrane to the substance. Substances that are easy to pass through include O2, CO2, N2, ethanol, urea, and water molecules.

Transmembrane transport mediated by carrier and channel membrane proteins: It is a passive transport, and the transport process itself does not need to consume energy, and it is a trans-membrane transport of substances along the concentration gradient or potential gradient. Facilitation diffusion through carriers refers to glucose, amino acids, nucleotides, etc.; Channel-facilitated diffusion refers to charged ions such as Na+, C1-, Ca2+, and K+ in solution, and the ion envy channels are divided into voltage-gated channels, chemically gated channels and mechanically gated channels.

Active transport: primary active transport and secondary active transport. The membrane protein that is actively transported in primary is the ion pump (sodium-potassium pump, abbreviated as sodium pump, also known as Na+-K+-ATPase).

Secondary active transport: It is an active transport process that indirectly utilizes ATP energy.

Summary. Dear, what do you want to know about sodium-potassium pumps? Can you add a question.

The sodium-potassium pump can transport Na+ from outside to intracellular, and from intracellular to extracellular, while transporting K+ from intracellular to extracellular.

Dear, what do you want to know about sodium-potassium pumps? Can you add a question.

Judge right from wrong. Yes, the crude potassium pump of the sodium source wheel can transport extracellular Na+ to the cell in a negative vertical gradient, while at the same time, it can also transport the intracellular K+ to the outside of the cell in a positive vertical gradient. In addition, the sodium-potassium pump can transport other ions (e.g., hail Ca2+) from the cell bush to the extracellular.

Answer] :d resting state, the concentration of K+ in the cell membrane is about 30 times that of the outside of the membrane, and the concentration of Na+ outside the membrane is 10 times that of the inside of the membrane. The maintenance of Na+ and K+ inside and outside the cell membrane is the result of the action of Na+ -K+ pump.

Pump is a special protein that is widely distributed in the lipid bilayer on the cell membrane of various cells. The physiological significance of the sodium pump is to establish a reserve of potential energy for other energy-consuming activities of the cell. When the cell membrane is quiet, it is permeable to K+, and there is K+ efflux in the void. The increase of Na+ permeability and the occurrence of Na+ influx (facilitated diffusion of Na+) during excitation are passive transport along the concentration difference, so they do not contribute to the formation and maintenance of the normal Na+ and K+ concentration difference inside and outside the cell membrane.

The Ca2+ pump effect on the cell membrane contributes to the formation and maintenance of the Ca2+ concentration difference inside and outside the cell membrane, but has no direct effect on the formation and maintenance of the Na+ and K+ concentration difference. This characteristic of sodium pump has been tested many times, and it is almost the original question, such as [2003N02], [1998N03], [1996N01], [1991NO114].

Answer] Bad game: Sodium pump is a sodium-potassium pump, which is a membrane protein with ATPase activity and is directly involved in the active transport process of Na+ and K+. When there is more Na+ in the cell membrane and more K+ outside the membrane, sodium pump activity can be initiated.

For every 1 molecule of ATP that is decomposed during its activity, 3 Na+ can be pumped out of the membrane and 2 K+ into the membrane by inverting the concentration differencePhysiological significance: Causes intracellular high potassium, which provides the basis for metabolic processes; Causes low sodium in the cells to prevent too much water from entering the cells; Establish potential energy reserves for other energy-consuming processes, such as secondary active transport.

Answer]: In the transport of substances in the cell membrane, it is difficult for various charged ions to pass through the cell membrane in a simple diffusion way, and usually the mediation of membrane proteins is required to complete the transmembrane transport. The membrane proteins that mediate Na+ trans-membrane transport include channels, ion pumps, and transporters.

The former is mediated by Na+ channels, which is transported along the concentration difference and potential difference, and belongs to facilitated diffusion. The ion pump that mediates Na+ transport is Na+-K+ pump, which directly uses the nuclear mountain dry energy generated by metabolism to transport Na+ across the membrane against the concentration difference and potential difference, which is the primary active transport. The transporter-mediated transport is carried out indirectly by using the Na+ concentration difference formed by the decomposition of ATP by the Na+ pump, which is a secondary active transport.