Mandela, the former president of the Republic of South Africa and Nobel Peace laureate, spent more than 40 yearsâ27 of them in prisonâas a central figure in the struggle against South Africaâs brutal and restrictive racial regime called apartheid.
meristem culture. (shoot-tip culture) The culture of excised meristems on suitable nutrient media under aseptic conditions. The stem apex is usually used though axillary meristems may also be taken.Often gibberellic acid must be added to the medium to promote normal growth into a plantlet.shoot-tip culture) The culture of excised meristems on suitable nutrient media under aseptic conditions. The stem apex is usually used though axillary meristems may also be taken. Often gibberellic acid must be added to the medium to promote normal growth into a plantlet.
Meristem tissue is not autonomous. Throughout the life of the plant, the rate of cell division and cell elongation in the meristems is regulated by plant hormones. For example, giberellins stimulate cell division in shoot apical meristem, causing the plant to grow taller.oth roots and shoots have meristematic tissue at their tips called apical meristems that are responsible for the lengthening of roots and shoots. The shoot apical meristem is formed during embryonic development, but after germination gives rise to the stem, leaves, and flowers.