13B – Distribution and constituents of fluids
P3: Distribution and constituents of body fluids –
M2: Explain functions of the constituents of body fluids -
Constituents of body fluid -
The human body consists mostly of water, and is a major constituent to the human body and vital organs; of this 90% include blood plasma, lymph, urine, saliva, digestive juices, bile, cerebrospinal fluid and tissue fluid. Water enables substances to be transported throughout the body, red blood cells for example, as wells as supplying the medium required for metabolic reaction to take place (respiration). Without water the progression of these fluids would not be possible. Water is constantly ...view middle of the document...
The excess amino acids made during this process are unable to be stored in the body as they can become toxic; therefore they would then have to be converted into a less toxic urea before ultimately being removed as a component of urine.
Acids, bases and salt –
Acids are a substance that has a pH less than 7. There are two different types of acid:
• Weak acid – An organic compound with a minimal amount of dissociated molecules
• Strong acid – An organic compound with a large amount of dissociated molecules
Acids are a corrosive substance with a pH less than 7. Acidity is caused by a high concentration of hydrogen ions.
Bases are a substance with a pH higher than 7, and have a high concentration of hydroxyl ions. Bases can react with acids in order to neutralise them in order to form salt and water. Bases are normally metal oxides or metal hydroxides. Sodium hydroxide for example is a base.
Acids react with reactive metals in order to make a salt. Salts are a compound formed by the neutralisation of an acid by a base, for example metal oxide. This is a result of hydrogen atoms in an acid being replaced by positive ions.
Bases that have are able to dissolve into water are known as alkalis. Sodium hydroxide is an alkali as it dissolves in water, copper oxide cannot dissolve water therefore is not an alkali.
Hydrochloric acid is produced in the stomach, consisting of chloride and hydrogen. Carbonic acid is produced in red blood cells consisting of carbon dioxide and water, of which is why demanding exercise can lead to the increase in the acidity of the individual’s blood.
Control of osmosis -
Salts are a major constituent of blood, and the levels both inside and outside of the cell, of which can be controlled by ATP. The sodium salts and chloride ions are continuously pumped back out of the cell each time they enter a cell, whereas potassium are pumped back into the cell as they leave a cell. The movement of salts enable the individual in assisting osmosis through the cell membrane.
Isotonic - Osmotic pressure outside the cell is equal to that inside of the cell. Water moving into and out of the cell is the same.
Hypotonic - Osmotic pressure is lower. Water moving into the cell is greater than that of which is moving out of the cell.
Hypertonic - Osmotic pressure is higher. Water moving out of the cell is greater than that of which is moving into the cell.
Role of electrolytes –
Electrolytes are compounds that dissociate into ions when they are dissolved in water, thereby causing them to become electrically charged particles, meaning that they have the ability to conduct electrical impulses. The electrical impulses created are what the body needs in order to make muscle cells contract. Electrolytes can become either cations (positively charged) or anions (negatively charged).
Essential minerals - Some electrolytes are considered essential minerals, meaning that they are unable to be...