Intracellular fluid | biochemistry | cypenv.info
Intracellular fluid: extracellular fluid: It differs from intracellular fluid (fluid within the cells) in that it generally has a high concentration of sodium and low. Dec 29, In this lesson you will find the definition of intracellular fluid. Finally, the relationship of electrolytes and intracellular fluid will be explained. All the fluid outside of the cell is called extracellular fluid (ECF) and is separated. Distinguish between intracellular and extracellular fluids to compare the position and characteristics of fluid in relation to the fluid within other compartments.
In addition, the composition of intracellular fluid and how water moves in and out of the cell will be provided.
Finally, the relationship of electrolytes and intracellular fluid will be explained. What is Intracellular Fluid? Human cells are bathed in fluids both inside the cell and out.
The fluid inside the cell is called intracellular fluid ICF. All the fluid outside of the cell is called extracellular fluid ECF and is separated from the intracellular fluid by a semipermeable membrane that surrounds the cell.
This membrane allows fluid to flow in and out, but prevents unwanted molecules or materials from getting in.
The remaining one-third of body water is outside cells, in the extracellular fluid compartment ECF. Exchange of gases, nutrients, water, and wastes between the three fluid compartments of the body.
In the image above, the ECF compartment is divisible in two compartments: Composition of body fluids Electrolytes and Nonelectrolytes Nonelectrolytes have bonds usually covalent bonds that prevent them from disassociating in a solution.
Because of this, no electrically charged species are created when nonelectrolytes dissolve in water. Most nonelectrolytes are organic molecules — lipids, glucose, urea, creatinine, for example.
Extracellular fluid - Wikipedia
In contrast, electrolytes are chemical compounds that do disassociate into ions in water. For the most part, electrolytes include organic salts, some proteins, and both organic and inorganic acids and bases. Electrolytes have much greater osmotic power than nonelectrolytes because each electrolyte molecule disassociates into at least two ions. For instance, a molecule of sodium chloride NaCl contributes twice as many solute particles as glucose, and a molecule of magnesium chloride MgCl2 contributes three times as many.
Regardless of the type of solute particle, water always moves according to osmotic gradients — from an area of lesser osmolarity to an area of greater osmolarity. For this reason, electrolytes have the greatest ability to cause fluid shifts. We can compute the concentration of any solution using the following equation: We could do the same thing for calcium: Comparison of Extracellular and Intracellular Fluids If you look at the bar graph above you can see that each fluid compartment has a distinctive pattern of electrolytes.
The lymphatic system returns protein and excess interstitial fluid to the circulation. The ionic composition of the interstitial fluid and blood plasma vary due to the Gibbs—Donnan effect. This causes a slight difference in the concentration of cations and anions between the two fluid compartments. Cell membrane details between extracellular and intracellular fluid Sodium-potassium pump and the diffusion between extracellular fluid and intracellular fluid The extracellular fluid provides the medium for the exchange of substances between the ECF and the cells, and this can take place through dissolving, mixing and transporting in the fluid medium.
These and many other substances occur, especially in association with various proteoglycans to form the extracellular matrix or the "filler" substance between the cells throughout the body. Regulation[ edit ] The internal environment is stabilised in the process of homeostasis.
Body Water Content
Complex homeostatic mechanisms operate to regulate and keep the composition of the ECF stable. Individual cells can also regulate their internal composition by various mechanisms. There is a significant difference between the concentrations of sodium and potassium ions inside and outside the cell. The concentration of sodium ions is considerably higher in the extracellular fluid than in the intracellular fluid.
These differences cause all cell membranes to be electrically charged, with the positive charge on the outside of the cells and the negative charge on the inside.
In a resting neuron not conducting an impulse the membrane potential is known as the resting potentialand between the two sides of the membrane is about mV. The maintenance of this difference in the concentration of ions between the inside of the cell and the outside, is critical to keep normal cell volumes stable, and also to enable some cells to generate action potentials.
Body Fluids : Anatomy & Physiology
This allows a brief inflow of sodium ions into the cell driven in by the sodium ion concentration gradient that exists between the outside and inside of the cell. This causes the cell membrane to temporarily depolarize lose its electrical charge forming the basis of action potentials. The sodium ions in the ECF also play an important role in the movement of water from one body compartment to the other.
When tears are secreted, or saliva is formed, sodium ions are pumped from the ECF into the ducts in which these fluids are formed and collected. The water content of these solutions results from the fact water follows the sodium ions and accompanying anions osmotically.