Answer to Question #114543 in Cell Biology for Valentina

Question

In terms of osmosis and tonicity, what happens to the solute concentration in solutions surrounding the cells when you eat salty foods, and how does that affect your cells?

Answer 1

To survive everyone needs to consume Sodium regularly. It is a principal component of a person’s internal environment – the extracelluar fluid. Nutrients reach your body’s cells through these fluids. Sodium facilitates many bodily functions including fluid volume and acid-base balance. Sodium enables the transmission of nerve impulses around the body. It is an electrolyte, like Potassium, Calcium and Magnesium; it regulates the electrical charges moving in and out of the cells in the body. It controls your taste, smell and tactile processes. The presence of Sodium ions is essential for the contraction of muscles, including that largest and most important muscle, the heart. It is fundamental to the operation of signals to and from the brain.

Chlorine too is essential to good health and is a fundamental element in the digestion process. It preserves the acid-base balance in the body. It aids Potassium absorption. It supplies the essence of Hydrochloric Acid in the gastric juices used in the stomach to help us break down and digest the food we eat and control the level of bacteria present in the stomach. It enhances the ability of the blood to carry Carbon Dioxide from respiring tissues to the lungs.

Too much sodium in the surrounding body fluid - or too little in the cells - is called hypernatremia. In hypernatremia, the excess sodium in the body fluid sucks too much water out of the cells. These dehydrated cells and their organelles shrink, crushing vital internal machinery.

Too little sodium in the surrounding fluid - or too much within the cells - is called hyponatremia. In all of these cases, hyponatremic cells swell as their higher sodium concentration draws too much water in, which eventually causes cell and organelle membranes to burst, spilling the contents into the surrounding environment and killing the cell.

The sodium-potassium pump is the locus of a constant exchange of electrical charge across cell membranes. It trades positively charged sodium ions for negatively charged potassium ones and allows the transfer of substances across cell membranes. The sodium-potassium pump also generates the electrical impulses necessary for nerve signals. Sodium imbalances interfere with this exchange and with the ability to receive and transmit signals. If the interference is great enough or lasts long enough, the sodium imbalance will paralyze the cells' transport and communication systems and kill the organism.