At this point esch chromosome consist of a pair of chromatids and the two associated chromosomes are termed a tetrad.
此时每条染色体由一对染色单体构成,这两条联合的染色体称为四分体。
原声例句
美国历史
Congress in the Esch-Cummins railway bill of the same year created a federal board of nine members to which all railway controversies, not settled by negotiation, must be submitted.