Bilirubin (Definition) Bilirubin is the potentially toxic product of heme metabolism. It is formed by breakdown of heme present in hemoglobin, myoglobin, cytochromes, catalase, peroxidase and tryptophan pyrrolase. Eighty percent of the daily bilirubin production comes from hemoglobin.
1. the act or fact of shrinking. 2. the amount by which anything decreases in size, value, weight, etc. 3. (Agriculture) the loss in body weight during shipment and preparation of livestock for marketing as meat. 4. (Commerce) the loss of merchandise in a retail store through theft or damage.
Atrophy resulting from disease of the tissue itself, or loss of trophic support due to other disease is termed pathological atrophy. Shrinkage in the size of the cell by loss of cell substance is known as atrophy. It represents a form of adaptive response and may culminate in cell death.ormonal and nerve inputs that maintain an organ or body part are referred to as trophic. Atrophy is a general physiological process of reabsorption and breakdown of tissues, involving apoptosis on a cellular level. It can be part of normal body development and homeostatic processes, or as a result of disease.