What is the difference between cytosol and interstitial fluid

The content inside the cell, which is encircled by the cell membrane is also called the cytosol. The cytosol mainly comprises water. Therefore, the pH of the cytosol is 7. The concentration of sodium, calcium, and chloride ions in the cytosol is lower than that of the external environment of the cytosol. However, potassium and magnesium ion concentration in the cytosol is higher than that of the external environment of the cell.

The low concentration of calcium ions in the cytosol allows the signal transduction inside the cell. A lot of proteins are found dissolved in the cytosol. This includes proteins such as microtubules , microfilaments , and intermediate filaments, which make up the cytoskeleton. The cytosol is not considered as an ideal solution due to its highly concentrated nature. The intracellular fluid along with the other fluids are shown in figure 1. Figure Intracellular fluid and other body fluids.

The extracellular fluid ECF refers to all the fluid outside the cell. Tissue fluid and plasma are the two major components of the ECF. The majority of the interstitial space functions as an ECM, a fluid space consisting of cell-excreted molecules that lies between the basement membranes of the interstitial spaces. The interstitial ECM contains a great deal of connective tissue and proteins such as collagen that are involved in blood clotting and wound healing.

Transcellular fluid is the portion of total body water contained within the epithelial-lined spaces. It is the smallest component of extracellular fluid, which also includes interstitial fluid and plasma. It is often not calculated as a fraction of the extracellular fluid, but it is about 2.

Examples of this fluid are cerebrospinal fluid, ocular fluid, joint fluid, and the pleaural cavity that contains fluid that is only found in their respective epithelium-lined spaces. The function of transcellular fluid is mainly lubrication of these cavities, and sometimes electrolyte transport.

Learning Objectives Distinguish between intracellular and extracellular fluids. Key Points The intracellular fluid of the cytosol or intracellular fluid or cytoplasmic matrix is the liquid found inside cells. The cytosol is a complex mixture of substances that include proteins, ions, and organelles dissolved in water. Therefore, intracellular and interstitial fluids are two types of body fluids.

Overview and Key Difference 2. What is Intracellular Fluid 3. What is Interstitial Fluid 4. Similarities — Intracellular and Interstitial Fluid 5. Intracellular vs Interstitial Fluid in Tabular Form 6. Summary — Intracellular vs Interstitial Fluid. Intracellular fluid is the fluid contained within cells. It consists of cytosol and fluid within the cell nucleus. The cytosol is the matrix in which cellular organelles are suspended.

Cytosol and organelles together make the cytoplasm. The fluid component of the nucleoplasm in the cell nucleus is called the nucleosol.

Intracellular fluid accounts for about 28 litres or 7. The fluid volume of ICF tends to be very stable. Edema is the accumulation of excess water in the tissues. It is most common in the soft tissues of the extremities.

The physiological causes of edema include water leakage from blood capillaries. Edema is almost always caused by an underlying medical condition, by the use of certain therapeutic drugs, by pregnancy, by localized injury, or by an allergic reaction. In the limbs, the symptoms of edema include swelling of the subcutaneous tissues, an increase in the normal size of the limb, and stretched, tight skin.

One quick way to check for subcutaneous edema localized in a limb is to press a finger into the suspected area. People with pulmonary edema likely will experience difficulty breathing, and they may experience chest pain. Pulmonary edema can be life threatening, because it compromises gas exchange in the lungs, and anyone having symptoms should immediately seek medical care. The resulting increased hydrostatic pressure within pulmonary capillaries, as blood is still coming in from the pulmonary arteries, causes fluid to be pushed out of them and into lung tissues.

A decrease in the normal levels of plasma proteins results in a decrease of colloid osmotic pressure which counterbalances the hydrostatic pressure in the capillaries. This process causes loss of water from the blood to the surrounding tissues, resulting in edema. Figure 8. An allergic reaction can cause capillaries in the hand to leak excess fluid that accumulates in the tissues. Mild, transient edema of the feet and legs may be caused by sitting or standing in the same position for long periods of time, as in the work of a toll collector or a supermarket cashier.

Otherwise, the venous blood pools in the lower limbs and can leak into surrounding tissues. Medications that can result in edema include vasodilators, calcium channel blockers used to treat hypertension, non-steroidal anti-inflammatory drugs, estrogen therapies, and some diabetes medications. Underlying medical conditions that can contribute to edema include congestive heart failure, kidney damage and kidney disease, disorders that affect the veins of the legs, and cirrhosis and other liver disorders.

Therapy for edema usually focuses on elimination of the cause. Activities that can reduce the effects of the condition include appropriate exercises to keep the blood and lymph flowing through the affected areas.

Other therapies include elevation of the affected part to assist drainage, massage and compression of the areas to move the fluid out of the tissues, and decreased salt intake to decrease sodium and water retention. Your body is mostly water. Body fluids are aqueous solutions with differing concentrations of materials, called solutes.

An appropriate balance of water and solute concentrations must be maintained to ensure cellular functions. If the cytosol becomes too concentrated due to water loss, cell functions deteriorate.

If the cytosol becomes too dilute due to water intake by cells, cell membranes can be damaged, and the cell can burst. Hydrostatic pressure is the force exerted by a fluid against a wall and causes movement of fluid between compartments.

Fluid can also move between compartments along an osmotic gradient. Active transport processes require ATP to move some solutes against their concentration gradients between compartments. Passive transport of a molecule or ion depends on its ability to pass easily through the membrane, as well as the existence of a high to low concentration gradient. Answer the question s below to see how well you understand the topics covered in the previous section.

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