Science

Lymph Node Definition Lymph nodes (or Lymph gland) are small lumps of tissue that contain white blood cells, which fight infection. They filter lymph fluid,…

Pyrite Definition Pyrite (FeS2) is a silver to yellow, metallic, cubic mineral. Pyrite often crystallizes in cubes or octahedrons but also occurs as shapeless masses…

Mediastinum Definition Mediastinum is the area in the chest between the lungs that contains the heart, part of the windpipe (the trachea), the esophagus, and…

Tantalum Definition Tantalum is a hard, heavy, gray metallic element that is highly resistant to corrosion at low temperatures. It is almost immune to chemical…

Chalcocite Definition Chalcocite (Cu2S) is a lead-grey or black mineral, found as a copper ore or in veins. It is a source of copper. It…

Thymus Gland Definition Thymus gland is an organ of the lymphatic system located behind the upper sternum (breastbone). T cells (T lymphocytes) develop and mature…

Uses of Arsenic Arsenic is a well-known poison. Arsenic compounds are sometimes used as rat poisons and insecticides but their use is strictly controlled. Surprisingly, arsenic…

Pyrochlore Definition Pyrochlore is a complex oxide mineral (Na,Ca)2Nb2O6(OH,F), which is composed of niobium, sodium, and calcium that forms brown to black, glassy octahedral crystals…

Arsenic is highly toxic in its inorganic form. Contaminated water used for drinking, food preparation and irrigation of food crops poses the greatest threat to…

Nasal Concha Definition Nasal concha also called Turbinate, or Turbinal, any of several thin, scroll-shaped bony elements forming the upper chambers of the nasal cavities.…

Industrial Uses of Mercury Some common uses for mercury are to conduct electricity, measure temperature and pressure, act as a biocide, preservative, and disinfectant, as well…

Hay Fever Definition Hay fever is a seasonal allergy to airborne particles characterized by itchy eyes, runny nose, nasal congestion, sneezing, itchy throat, and excess…