Lecture-2 Water, Acids, Bases, and Buffers PDF

  Guyton and Hall Textbook of Medical Physiology states that "the normal pH of arterial blood is 7.4, with a range of 7.35 to 7.45."  According to Journal of Investigative Dermatology on 2016 pH of human sweat typically ranges from 4.5 to 7.0, making it slightly aci...

  Guyton and Hall Textbook of Medical Physiology states that "the normal pH of arterial blood is 7.4, with a range of 7.35 to 7.45."  According to Journal of Investigative Dermatology on 2016 pH of human sweat typically ranges from 4.5 to 7.0, making it slightly acidic to neutral. The pH can vary depending on factors such as hydration, diet, and the environment. This acidity is partly due to the presence of lactic acid and urea in sweat, which helps protect the skin from harmful bacteria and maintain the skin's barrier function.  normal pH range of human urine typically falls between 4.6 and 8.0, with an average around 6.0, which is slightly acidic. The exact pH can vary depending on factors such as diet, hydration, and overall health. For example, a diet high in protein tends to produce more acidic urine, while a diet rich in fruits and vegetables can result in more alkaline urine.  According to World Health Organization normal pH of human semen typically ranges from 7.2 to 8.0, which is slightly alkaline. This alkalinity helps to protect sperm as they travel through the acidic environment of the female reproductive tract. Maintaining this pH is important for sperm motility and overall fertility.  Guyton and Hall Textbook of Medical Physiology on 2016 normal pH of human gastric juice ranges from 1.5 to 3.5, making it highly acidic. This acidity is primarily due to the presence of hydrochloric acid (HCl), which plays a crucial role in digestion by breaking down food, activating digestive enzymes, and killing harmful bacteria.  Journal of Dental Research (2017) normal pH of human saliva typically ranges from 6.2 to 7.6, which is slightly acidic to neutral. This pH range helps in maintaining oral health, as it supports the initial stages of digestion and provides a protective environment against harmful bacteria. The Bronsted-Lowry acid is a substance which donates a proton or H+ ion to the other compound. The Bronsted-Lowry base is a substance which accepts a proton or H+ ion from other compounds.  Water exhibits amphiprotic character, (A species that has the potential to act both as an acid and as a base) i.e. it will dissociate to produce H3O+ ions and OH- ions. In this phenomenon, some molecules of H2O will act as acids, each donating a proton to a corresponding H2O molecule that acts as a base. The reaction of an acid and a base, which forms water and a salt. pH, quantitative measure of the acidity or basicity of aqueous or other liquid solutions. A buffer is a solution that can resist pH change upon the addition of an acidic or basic components Maintaining a constant blood pH is critical for the proper functioning of our body. The buffer that maintains the pH of human blood involves a carbonic acid (H2CO3) - bicarbonate ion system (HCO3 ). - The excessive acidity of acids and bases, of the blood, and other body fluids is known as acidosis. Common causes of acidosis are situations and disorders that reduce the effectiveness of breathing, especially the person’s ability to exhale fully, which causes a buildup of CO2 (and H+) in the bloodstream. Acidosis can also be caused by metabolic problems that reduce the level or function of buffers that act as bases, or that promote the production of acids. For instance, with severe diarrhea, too much bicarbonate can be lost from the body, allowing acids to build up in body fluids.  In people with poorly managed diabetes (ineffective regulation of blood sugar), acids called ketones are produced as a form of body fuel. These can build up in the blood, causing a serious condition called diabetic ketoacidosis. Kidney failure, liver failure, heart failure, cancer, and other disorders also can prompt metabolic acidosis.  Alkalosis is a condition in which the blood and other body fluids are too alkaline (basic). In respiratory alkalosis, carbon dioxide levels fall too low Lung disease, aspirin overdose, shock, and ordinary anxiety can cause respiratory alkalosis, which reduces the normal concentration of H+.