K+, P 2-, and Mg 2+ are intracellular ions, and Na + and Cl - are predominantly extracellular. View chapter Purchase book Cellular Physiology Linda S. Costanzo PhD, in Physiology, 2018 Composition of Intracellular Fluid and Extracellular Fluid
Extracellular fluid
Extracellular fluid (ECF) or extracellular fluid volume (ECFV) usually denotes all body fluid outside the cells. The remainder is called intracellular fluid (ICF). The ECF and ICF are the two major fluid compartments.
What is the intracellular fluid composed of?
Unlike extracellular fluid, the intracellular fluid has a high concentration of potassium and a low concentration of sodium. The cytosol is composed primarily of water, dissolved ions, small molecules, and large molecules soluble in water (such as proteins). Its molecules are important for cell metabolism.
What is the predominant cation in intracellular fluid?
Intracellular fluid s, amounting to 33 percent of body weight, have potassium as their predominant cation. These various “compartments” of body fluid are in osmotic equilibrium, so that if solute ( e.g., sodium chloride) is added to the extracellular compartment so as to increase the concentration of…
Which ions are intracellular and extracellular?
K+, P 2-, and Mg 2+ are intracellular ions, and Na + and Cl - are predominantly extracellular. Lara Primak, Jeffrey L. Blumer, in Pediatric Critical Care (Third Edition), 2006 Intracellular Fluid Volume.
What ions are in the ECF of the body?
Most body fluids are neutral in charge. Thus, cations, or positively charged ions, and anions, or negatively charged ions, are balanced in fluids. As seen in the previous graph, sodium (Na+) ions and chloride (Cl–) ions are concentrated in the ECF of the body, whereas potassium (K+) ions are concentrated inside cells.
What is intracellular fluid made of?
The cytosol or intracellular fluid consists mostly of water, dissolved ions, small molecules, and large, water-soluble molecules (such as proteins). This mixture of small molecules is extraordinarily complex, as the variety of enzymes that are involved in cellular metabolism is immense. Ions: Ions in solution.
Which ion is most common in intracellular fluid?
The most abundant cation in intracellular fluid is sodium. The most abundant cation (or positively charged ion) in the intracellular fluid (ICF) is potassium (K+).
What ion is higher in intracellular and extracellular fluid?
potassium ionsWhen a neuron is at rest, potassium ions (K+) are at a higher concentration inside the membrane in the intracellular fluid or cytoplasm than outside in the extracellular fluid. Potassium ions pass through the pores of the neuronal membrane with ease.
What are the 4 cations in the cellular fluids?
Sodium. Sodium is the major cation of the extracellular fluid. ... Potassium. Potassium is the major intracellular cation. ... Chloride. Chloride is the predominant extracellular anion. ... Bicarbonate. Bicarbonate is the second most abundant anion in the blood. ... Calcium. ... Phosphate.
What is only found in intracellular fluid?
For intracellular fluid, the most important electrolyte is potassium (K+ ), followed by magnesium and phosphate. Only small amounts of sodium, chloride, and bicarbonate are found in the intracellular fluid.
What is the most abundant anion in the intracellular fluid quizlet?
The most abundant cation in the intracellular fluid (ICF) is potassium (K+). The most abundant anion in the ICF is hydrogen phosphate (HPO4-).
Which ion has the highest intracellular concentration?
Sodium, potassium, and chloride ions are present in the highest concentrations and therefore generally play the most important roles in the generation of the resting membrane potential....IonExtracellular mmol/lIntracellular mmol/lCl-11010K+51501 more row
What is the most abundant electrolyte in the intracellular fluid?
potassiumThe most abundant electrolyte in intracellular fluid is potassium. Intracellular fluids are crucial to the body's functioning. In fact, intracellular fluid accounts for 60% of the volume of body fluids and 40% of a person's total body weight! Extracellular fluids (ECF) are fluids found outside of cells.
What is the different between intracellular fluid and extracellular fluid?
The intracellular fluid is the fluid contained within cells. The extracellular fluid—the fluid outside the cells—is divided into that found within the blood and that found outside the blood; the latter fluid is known as the interstitial fluid.
What ions are in the body?
Many normal substances exist in the body as ions. Common examples include sodium, potassium, calcium, chloride, and bicarbonate. These substances are known as electrolytes. Ions can be created using radiation such as x-rays.
What is the major electrolyte in extracellular fluid?
SodiumSodium, which is an osmotically active cation, is one of the most important electrolytes in the extracellular fluid. It is responsible for maintaining the extracellular fluid volume, and also for regulation of the membrane potential of cells.
Which ion has the highest intracellular concentration?
Sodium, potassium, and chloride ions are present in the highest concentrations and therefore generally play the most important roles in the generation of the resting membrane potential....IonExtracellular mmol/lIntracellular mmol/lCl-11010K+51501 more row
Which ion has the highest concentration in the intracellular spaces?
As the most abundant cation in intracellular fluid, potassium plays an important role in a variety of cell functions.
Which is the most abundant element in cell fluid?
Water Is the Most Abundant Substance in Cells In each water molecule (H2O) the two H atoms are linked to the O atom by covalent bonds (see Figure 2-12).
What are examples of extracellular fluid?
Extracellular fluid refers to the fluid that is found outside of the cell. Extracellular fluid is found in blood plasma and in the interstitial spa...
What is meant by intercellular fluid?
Intracellular fluid refers to the fluid content found inside of the cell. Because intracellular fluid is found inside of the cell, it is sometimes...
What is the main function of intracellular fluid?
The main function of intracellular fluid is to help with the transport of gases, nutrients, and other molecules. Intracellular fluid is also import...
What is intracellular fluid?
ICF is defined as all the body water within cells and, unlike the ECF compartment, is an inhomogeneous, multicompartmental entity, with different pH and ionic compositions depending upon the organ or tissue being considered. From: Oh's Intensive Care Manual (Seventh Edition), 2014.
What is the percentage of intracellular fluid?
Intracellular fluid (ICF) represents about two thirds of the TBW, which is equivalent to 30% to 40% of total body weight. However, the proportion of ECF is much greater than that of ICF in preterm infants and reaches 60% of TBW at term. The membranes retaining this fluid allow the passive diffusion of water, whereas active transport mechanisms maintain an internal solute milieu different from that found outside the cells. K+, P 2-, and Mg 2+ are intracellular ions, and Na + and Cl - are predominantly extracellular.
Which cell membranes are largely restricted to one compartment?
Effective osmoles are those that cause water to move across cell membranes because they are largely restricted to one compartment (e.g., Na +, glucose, or mannitol in the ECF compartment).
What is the ICF volume?
The ICF volume represents the fluid content within the body's cells. This volume cannot be measured directly but is calculated as the difference between the measured TBW and the measured ECF volume. Potassium provides the osmotic skeleton for the ICF in much the same way that sodium provides the osmotic skeleton for the ECF. Because water is freely diffusible into and out of the cell, changes in the tonicity of the ECF are rapidly reflected by similar changes in ICF tonicity ( Saxton and Seldin, 1986). This is largely the result of the movement of water across the cell membrane with resultant changes of ICF volume. Thus, whereas plasma sodium concentration decreases in response to water retention, ICF volume increases (Humes, 1986 ). On the other hand, with water depletion resulting in hypernatremia, ICF volume decreases ( Humes, 1986 ). Relatively little is known about the organization of intracellular water into the various subcellular compartments and organelles.
Why do cells die during cryolesion?
Some cells die as a direct result of dehydration, whereas others require the added insult provided during isotonic rehydration, which occurs during the thaw cycle. When the cryolesion thaws, the extracellular fluid melts first, briefly creating a relatively hypotonic environment.
How does tissue cooling affect cell survival?
The rate at which tissue cools affects the proportion of cells killed by a single freeze cycle. Maximal cell death is achieved at slow and rapid cooling rates (although through different mechanisms), whereas greatest cell survival is seen with intermediate cooling rates. Cellular dehydration causes lethal injury at slow cooling rates, whereas rapidly cooled cells are destroyed by the mechanical action of ice crystallization and expansion ( Fig. 98D.1 ).
Why does water freeze before intracellular fluid?
Because the composition of the intracellular and extracellular compartments differs markedly , the extracellular fluid freezes before the intracellular fluid.
What Is Intracellular Fluid?
Living organisms like humans and other mammals are comprised largely of water. Indeed, nearly 75% of the body weight in humans is made of water. This water is divided into two main components of the human body: extracellular fluid and intracellular fluid.
Intracellular Fluid vs Extracellular Fluid
As mentioned earlier in this lesson, water comprises up to 75% of the total body weight in humans. These fluids are divided into intracellular and extracellular fluids. There are several important differences between intracellular fluid versus extracellular fluid.
Osmosis and Intracellular Fluid
Intracellular and extracellular fluids travel through the body via both active and passive transport. However, intracellular fluid often moves between cells by passively traveling across the cell membranes. The flow of intracellular fluid is controlled in part by osmosis.
What is the difference between intracellular and extracellular fluid?
Unlike extracellular fluid, the intracellular fluid has a high concentration of potassium and a low concentration of sodium.
Where is intracellular fluid stored?
Therefore, this fluid is stored within the intracellular compartments of the body. The intracellular compartment is the system that includes all the fluids enclosed in ...
What is the fluid inside a cell called?
The fluid inside the cells is called intracellular fluid (IFC) and the fluid outside the cells is called the extracellular fluid (EFC). These two fluids are separated by a semipermeable membrane that surrounds the cell. This membrane makes it possible for the liquid to enter and exit, but at the same time prevents unwanted molecules ...
What is the opposite of intracellular fluid?
The opposite of the intracellular fluid is the extracellular fluid, which is located outside the cells in the extracellular compartment. Many enzymes and cellular mechanisms work to transport both products and wastes from the intracellular fluid to the extracellular fluid, while bringing new nutrients and solutes to the intracellular fluid.
Why is it important to keep the water balance inside the cell?
Since the concentration of proteins is high within the intracellular fluid compared to the extracellular fluid, the differences in ion concentrations both inside and outside the cell become important in order to regulate osmosis. This allows you to keep the water balance inside the cell to protect it and not to explode.
What is the intracellular compartment?
The intracellular compartment is the system that includes all the fluids enclosed in the cells by their plasma membranes. Representation of eukaryotic human cells. When talking about cellular functions, this type of fluid is often referred to as a cytosol. The cytosol, organelles and molecules that are located inside are collectively referred ...
What is the pH of the cytosol?
Most of the cytosol is composed of water, which makes up about 70% of the total volume of a typical cell. The pH of the intracellular fluid is 7.4. The cell membrane separates the cytosol from the extracellular fluid, but it can pass through the cytosol when necessary through specialized channels.
What is intracellular fluid?
In human disease: Fluid and electrolyte balance. The intracellular fluid is the fluid contained within cells. The extracellular fluid—the fluid outside the cells—is divided into that found within the blood and that found outside the blood; the latter fluid is known as the interstitial fluid. These fluids are not simply water but contain….
What is the difference between intracellular fluid and extracellular fluid?
comparison with extracellular fluid. In extracellular fluid. It differs from intracellular fluid (fluid within the cells) in that it generally has a high concentration of sodium and low concentration of potassium, while intracellular fluid is high in potassium and low in sodium. The fluid is often secreted by cells to provide a constant environment ...
Is intracellular fluid in osmotic equilibrium?
The intracellular fluid is the fluid contained within cells. The extracellular fluid—the fluid outside the cells—is divided into ...
What are the roles of ions in cells?
Ions have a huge variety of roles in cells. Several of our favorites include the role of ions in electrical communication (Na +, K +, Ca 2+ ), as cofactors in dictating protein function with entire classes of metalloproteins (constituting by some estimates at least ¼ of all proteins) in processes ranging from photosynthesis to human respiration ...
How do ion channels work?
Ion channels serve as passive barriers that can be opened or closed in response to environmental cues such as voltage across the membrane, the concentration of ligands or membrane tension. Pumps, by way of contrast, use energy in the form of protons or ATP in order to pump charged species against their concentration gradient. The differences in concentration mediated by these membrane machines can often be several orders of magnitude and in the extreme case of calcium ions correspond to a 10,000-fold greater concentration of ions outside of the cell than inside as shown in Table 1. The dominant players in terms of abundance inside the cell are potassium (K + ), chloride (Cl –) and magnesium (Mg 2+) (though the latter is mostly bound to ATP, ribosomes and other macromolecules and metabolites such that its free concentration is orders of magnitude lower). Table 1 shows some typical ionic concentrations in bacteria, yeast and mammalian cells. Some ion concentrations are regulated tightly, particularly toxic metal ions that are also essential for certain processes, but also regulation of K + by osmolarity, which is essential for growth. Other ions are less tightly regulated, Na + being one such example. One of the provocative observations that emerges from this table is that positive ions are much more abundant than negative ions. What is the origin of such an electric imbalance in the simple ions? Many of the metabolites and macromolecules of the cell are negatively charged. This negative charge is conferred by phosphate in small metabolites and DNA and by carboxylic groups on the acidic amino acids, such as the most abundant free metabolite, glutamate. Much more on these cellular players can be found in the vignette on “What are the concentrations of free metabolites in cells?”.
How is potassium in equilibrium?
Potassium is usually close to equilibrium in animal and plant cells. Given that its concentration inside the cell is about 10 to 30 fold higher than outside the cell, how can it be in equilibrium? Assume we start with this concentration difference across the membrane, and with no electric potential difference (there are counter ions on each side of the membrane to balance the initial charges and they cannot move). As the potassium ions diffuse down their concentration gradient, from the inside to the outside, they quickly create an electric potential difference due to their positive net charge (the net charge movement is miniscule compared to the ion concentrations on the two sides of the membrane as discussed in the vignette on “What is the electric potential difference across membranes?”). The potential difference will increase until its effect will exactly balance the diffusive flux and this is when equilibrium will be reached. This type of equilibrium is known as electrochemical equilibrium. Indeed from the equilibrium distribution we can infer that the cell has a negative electric potential inside and by how much. The direction of the voltage difference across the cell membrane is indeed from positive outside to negative inside as can be naively expected from pumping of protons out of the cell, and as discussed in quantitative terms in the vignette on “ What is the electric potential difference across membranes?”.
What is negatively charged in a cell?
Many of the metabolites and macromolecules of the cell are negatively charged . This negative charge is conferred by phosphate in small metabolites and DNA and by carboxylic groups on the acidic amino acids, such as the most abundant free metabolite, glutamate. Much more on these cellular players can be found in the vignette on “What are ...
What are the dominant players in terms of abundance inside the cell?
The dominant players in terms of abundance inside the cell are potassium (K + ), chloride (Cl –) and magnesium (Mg 2+) (though the latter is mostly bound to ATP, ribosomes and other macromolecules and metabolites such that its free concentration is orders of magnitude lower). Table 1 shows some typical ionic concentrations in bacteria, ...
How much does depolarization change the internal charge of a muscle cell?
Muscle cells in which such depolarization leads to muscle contraction often have a diameter of about 50 μm, and a simple estimate (BNID 111449) reveals that the change in the internal charge within the cell as a result of membrane depolarization is only about a thousandth of a percent (10 -5) of the charge within the cell.
What are the three regions of ionic composition?
Three distinct regions are characterized: the cellular interior (“intracellular fluid”), the medium between cells (“intercellular fluid”) and the blood plasma that is outside the tissue, beyond the capillary wall. The y-axis is in units of ionic concentration called Eq for “equivalents”, ...
Which ions are balanced in fluids?
Thus, cations, or positively charged ions, and anions, or negatively charged ions, are balanced in fluids. As seen in the previous graph, sodium (Na +) ions and chloride (Cl –) ions are concentrated in the ECF of the body, whereas potassium (K +) ions are concentrated inside cells.
What is the intracellular fluid?
Figure 2. The intracellular fluid (ICF) is the fluid within cells. The interstitial fluid (IF) is part of the extracellular fluid (ECF) between the cells. Blood plasma is the second part of the ECF. Materials travel between cells and the plasma in capillaries through the IF.
Why does pulmonary edema cause water to leak?
In pulmonary edema resulting from heart failure, excessive leakage of water occurs because fluids get “backed up” in the pulmonary capillaries of the lungs, when the left ventricle of the heart is unable to pump sufficient blood into the systemic circulation . Because the left side of the heart is unable to pump out its normal volume of blood, the blood in the pulmonary circulation gets “backed up,” starting with the left atrium, then into the pulmonary veins, and then into pulmonary capillaries. 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.
Where does hydrostatic pressure enter the capillaries?
Fluid and the cellular wastes in the tissues enter the capillaries at the venule end, where the hydrostatic pressure is less than the osmotic pressure in the vessel.
Where is the ECF found in the body?
The ECF accounts for the other one-third of the body’s water content. Approximately 20 percent of the ECF is found in plasma . Plasma travels through the body in blood vessels and transports a range of materials, including blood cells, proteins (including clotting factors and antibodies), electrolytes, nutrients, gases, and wastes. Gases, nutrients, and waste materials travel between capillaries and cells through the IF. Cells are separated from the IF by a selectively permeable cell membrane that helps regulate the passage of materials between the IF and the interior of the cell.
What are the dissolved substances in a solution called?
The chemical reactions of life take place in aqueous solutions. The dissolved substances in a solution are called solutes. In the human body, solutes vary in different parts of the body, but may include proteins—including those that transport lipids, carbohydrates, and, very importantly, electrolytes. Often in medicine, a mineral dissociated ...
How does water move through the body?
In the body, water moves through semi-permeable membranes of cells and from one compartment of the body to another by a process called osmosis. Osmosis is basically the diffusion of water from regions of higher concentration to regions of lower concentration, along an osmotic gradient across a semi-permeable membrane.
