1 There are two types of glial cells in the nervous system: the large-bodied macroglia and the smaller microglia. 2  There are two classes of macroglia in the central nervous system: astrocytes and oligodendrocytes.
Exports directly contribute and imports directly reduce their nation's balance of trade (i.e. net exports). A trade surplus is positive net balance of trade, and a trade deficit is a negative net balance of trade.
trade allowance. Discount offered by producers or marketers to distribution channel members (distributors, wholesalers, retailers) usually as a short-term promotional incentive. Its objective is to effect a lower retail price to stimulate sales. Not to be confused with trade discount.