(1) restriction enzyme and DNA ligase are needed to form recombinant plasmid. Because the ampicillin resistance gene was destroyed when the target gene was introduced, the tetracycline resistance gene was not destroyed, so tetracycline should be added to the culture medium to screen out the terminal bud cells into which the target gene was introduced. This medium is selective.

(2) Using plant tissue culture technology, the terminal bud of red bean shirt carrying the target gene was cultured in vitro and developed into seedlings. The principle is the totipotency of plant cells. After callus formation, due to the different realization of genetic information, various tissues and cells can be formed after redifferentiation.

(3) Before inoculation, the prepared MS medium should be sterilized by high-pressure steam to avoid the rapid growth of mixed bacteria on it, which will consume nutrients and some mixed bacteria will harm the growth of the culture. The synergistic effect of auxin and cytokinin is very important in the process of tissue culture, and these two plant hormones should be added to the culture medium. When adding hormones, it is necessary to control the concentration, use order and dosage ratio of the two hormones.

(4) When the terminal bud of Taxus chinensis is cut into single terminal bud cells in vitro, the usual method is enzymolysis, and the enzyme needed is pectinase.

So the answer is:

(1) restriction enzyme and DNA ligase tetracycline were used to screen terminal bud cells into which the target gene was introduced. choose

(2) The realization of universal genetic information is different.

(3) autoclaving auxin and cytokinin? Concentration, order of use and dosage ratio

(4) Pectinase