Category: P

An enzyme in the gastric juice which hydrolyses proteins to give smaller polypeptides; an endopeptidase. An enzyme found in gastric juice that promotes the digestion of proteins. A crystallizable proteinase (enzyme) that in an acidic medium digests (breaks down) most proteins to polypeptides. It is secreted by glands in the mucous membrane of the stomach…

The excretion of pentose sugars in the urine. Idiopathic pentosuria is an inherited metabolic disorder almost wholly restricted to Ashkenazi (North European) Jews, which has no adverse effects. Consumption of fruits rich in pentoses (e.g. pears) can also lead to (temporary) pentosuria. A condition in which pentose is present in the urine. A rare genetic…

Monosaccharide sugars with five carbon atoms. The most important is ribose. A simple sugar (monosaccharide molecule) whose backbone structure contains five carbon atoms. There exists many different pentoses. Some examples of pentoses are: ribose, arabinose, and xylose, to mention just a few. A monosaccharide containing five carbon atoms, having the chemical formula (CH20)5. A five-carbon…

Polysaccharides of five-carbon sugars (pentoses).  

Plant tissues contain hemicelluloses (polymers of galacturonic acid) known as protopectins which cement the cell walls together. As fruit ripens, there is maximum protopectin present; thereafter it breaks down to pectin, pectinic acid, and, finally, pectic acid, and the fruit softens as the adhesive between the cells breaks down. Water-soluble substances found in plant tissues…

Movement of solutes across cell membranes from an area of high concentration to an area of lower concentration. A process of diffusion by which substances move from one compartment to another down a concentration gradient and does not require energy. Movement of small molecules across a cell membrane by diffusion; it does not require the…

Any disorder of the sense of smell. A perverted sense of smell; everything may smell unpleasant to the affected individual. The most common cause is some septic condition of the nasal passage, but the condition may occasionally be due to a lesion in the brain involving the centre responsible for the sense of smell. Any…

EU term for foods prepared for particular nutritional purposes (intended for people with disturbed metabolism, or in special physiological conditions, or for young children). Also called dietetic foods.  

Jewish term for dishes containing neither milk nor meat. Orthodox Jewish law prohibits mixing of milk and meat foods or the consumption of milk products for 3 hours after a meat meal.  

Slow infusion of solution of nutrients into the veins through a catheter. This may be partial, to supplement food and nutrient intake, or total (TPN, total parenteral nutrition), providing the sole source of energy and nutrients for patients with major intestinal problems. The process of feeding someone by means other than the digestive tract, especially…