In the experiment of experimental pulmonary edema in mice, the purpose of ligation of trachea is to get the lung easily. ( )

在DNA重组连接时,常采用连接头连接(linker ligation),其作用是( )

Which of the following process needs primer? ( ) A: DNA replication B: RNA replication C: RNA transcription D: RNA translation E: DNA ligation

1.toddler age is from what time to what time? A: from delivery to 1 year old B: from 1 to 3 years old C: from fertilized ovum to delivery D: from umbilical ligation to 28thday E: from 6-7 years old to adolescence