Read the passage below and answer the questions that follow.
Plant cells possess totipotency, containing the complete genetic blueprint encoded as base sequences in their DNA, which allows them to regenerate into fully functional, genetically identical individuals. Micropropagation relies on isolating tiny segments of tissue, referred to as explants, from a donor Sweet Wormwood plant (Artemisia annua). These explants must undergo thorough surface sterilisation to eliminate contaminating microbes before transfer to an agar growth medium. This nutrient-rich agar is supplemented with sucrose, amino acids, inorganic mineral ions, and specific plant growth regulators.
Because every regenerated plantlet is a clone derived from a single high-yielding parent specimen selected for high artemisinin concentration, they possess an identical genotype. Furthermore, maintaining aseptic conditions throughout the culture process guarantees that the micropropagated clones are certified pathogen-free, preventing the spread of destructive viruses or systemic bacteria.
The primary global pharmaceutical interest in Artemisia annua lies in the extraction of artemisinin, a crucial active pharmaceutical ingredient (API) in malaria treatment. Traditionally, sourcing artemisinin relies on seasonal wild harvesting or unpredictable crop yields from seeds, which can lead to wild population depletion and volatile supply chains. In contrast, clearing extensive areas of natural vegetation to make way for massive monoculture farming has caused severe deforestation, resulting in devastating ecological impacts.
Utilising micropropagation to establish high-performing clonal lines of Artemisia annua in controlled, high-density cultivation facilities offers a sustainable way to meet global demand. This alleviates the pressure of wild over-harvesting. However, when natural forest ecosystems are cleared for agricultural expansion, it leads to rapid deforestation, causing environmental problems that extend far beyond simple loss of habitat.
Name one nitrogenous base found in DNA.
Suggest why explants are sterilised before being placed on the growth medium.
Suggest why amino acids are provided in the growth medium.
State what is meant by the term pathogen.
Suggest two reasons why growers prefer to use micropropagation rather than sexual reproduction (growing from seeds) to produce plants for artemisinin extraction.
Explain what is meant by a sustainable resource.
Deforestation can lead to the extinction of species. Give three other major environmental disadvantages of deforestation.
