a structure that looks like a very small piece of string and that exists, usually as one of a pair, in the central part of all living cells. Chromosomes contain genes. 染色体
[T]biologyto combine one breed of animal with another, or to mix one type of plant with another, in order to produce an animal or plant that is genetically different from both parents使(动植物)杂交
sciencea very small part of a cell, used in genetic engineering for carrying genetic material from one cell to another 载体(用于基因工程中,指细胞的一小部分,能将基因材料从一个细胞运送到另一个细胞)
a type of chromosome (=genetic material in a cell) that decides what sex a human or animal will be. In humans, females have two X-chromosomes and males have one. (细胞中能决定人或动物性别的)X染色体