If a team official, substitute, substituted or sent off player or outside agent enters the field of play the referee must: 1  only stop play if there is interference with play. 2  have the person removed when play stops. 3  take appropriate disciplinary action.
The bicarbonate ion (hydrogencarbonate ion) is an anion with the empirical formula H C O 3 â and a molecular mass of 61.01 daltons; it consists of one central carbon atom surrounded by three oxygen atoms in a trigonal planar arrangement, with a hydrogen atom attached to one of the oxygens.
They are adapted by four ways: 1  They have a biconcave disc shape that gives it a large surface area to carry more oxygen. 2  They contain a chemical called hemoglobin that combines with oxygen and carbon dioxide. 3  They have no nuclease to carry more oxygen and CO2. 4  They are tiny enough to squeeze through capillaries.