cambium ['kæmbɪrm]

例句:

• Acropetal differentiation of the cambium layer continues as the primary root elongates.
  形成层的向顶分化像初生根伸长一样在继续进行.
  
• The base of scoin is cut diagonally to expose a large oval of cambium.
  接穗的基部被切成斜形,暴露出椭圆形的大圈形成层.
  
• The callus originated from several parts , but mainly from cambium.
  愈伤组织是多起源的, 但主要源于形成层.
  
• If you kill the cambium, you can't grow the xylem there and so that year you end up with a scar, a fire scar.
  来自SA