Diabetes Glossary Terms: B-D

a viscous, bitter fluid produced by the liver and stored in the gall bladder. It is an alkaline solution of bile salts, pigments, some mineral salts and cholesterol, which aids in fat digestion and absorption of nutrients. Discharge of bile into the intestine is increased after food, and of the amount secreted each day (up to one litre), most is reabsorbed with the food, passing into the blood to circulate back to the liver. If the flow of bile into the intestine is restricted, it stays in the blood, resulting in jaundice.

the basic building block of all life and the smallest structural unit in the body. Human body cells vary in size and function and number several billion. Each cell consists of a cell body surrounded by a membrane. The cell body consists of a substance known as cytoplasm, containing various organelles and also a nucleus. The nucleus contains the chromosomes, composed of the genetic material, the DNA. Most human body cells contain 46 chromosomes (23 pairs), half being derived from the individual's father and half from the mother. Cells are able to make exact copies of themselves by a process known as mitosis, and a full complement of chromosomes is received by each daughter cell. However, the human sex cells (sperm and ova) differ in always containing half the number of chromosomes. At fertilization, a sperm and ovum combine and a complete set of chromosomes is received by the new embryo.

the rod-like structures, present in the nucleus of every body cell, that carry the genetic information or genes. Each human body cell contains 23 pairs of chromosomes, apart from the sperm and ova, half derived from the mother and half from the father. Each chromosome consists of a coiled double filament (double helix) of DNA, with genes carrying the genetic information arranged linearly along its length. The genes determine all the characteristics of each individual. Of the pairs of chromosomes, 22 are the same in males and females. The twenty-third pair are the sex chromosomes, and males have one X-chromosome and one Y-chromosome, whereas females have two X-chromosomes.

a wasting disease of childhood in which the intestines are unable to absorb fat. The intestinal lining is damaged because of a sensitivity to the protein gluten, which is found in wheat and rye flour. An excess of fat is excreted, and the child fails to grow and thrive. Successful treatment is by adhering strictly to a gluten-free diet throughout life.

a metabolic disorder that results from excessive amounts of corticosteroids in the body because of an inability to regulate Cortisol or adrenocorticotropic hormone (ACTH). The commonest cause is a tumour of the pituitary gland (producing secretion of ACTH) or a malignancy elsewhere, e.g. in the lung or adrenal gland, requiring extensive therapy with corticosteroid drugs. Symptoms include obesity, reddening of face and neck, growth of body and facial hair, osteoporosis, high blood pressure and possible mental disturbances.

(formerly mongolism) a syndrome created by a congenital chromosome disorder that occurs as an extra chromosome 21, producing 47 in each body cell. Characteristic facial features are produced - a shorter, broader face with slanted eyes (similar to the Mongolian races, hence the old-fashioned name). It also results in a shorter stature, weak muscles and the possibility of heart defects and respiratory problems. The syndrome also confers mental retardation. Down's syndrome occurs once in approximately 600 to 700 live births, and although individuals may live beyond middle age, life expectancy is reduced and many die in infancy. The incidence increases with the age of the mother, from 0.04 per cent of children to women under 30, to 3 per cent to women at 45. It is therefore likely that pregnant women over 35 will be offered an amniocentesis test.

the first part of the small intestine where food (chyme) from the stomach is subject to action by bile and pancreatic enzymes. The duodenum also secretes a hormone secretion that contributes to the breakdown of fats, proteins and carbohydrates. In the duodenum, the acid conditions pertaining from the stomach are neutralized and rendered alkaline for the intestinal enzymes to operate.