Answer: Plasmid.
A plasmid is a small DNA molecule within a bacteria cell that is separated from the chromosomal DNA and can replicate independently. Through Recombinant DNA, we can insert a gene that we want to see replicated in the plasmid, and when the bacteria multiplies, which it does often, we will obtain a lot of copies of interest gene.
Answer:
Molecular genetic approaches to the study of plant metabolism can be traced back to the isolation of the first cDNA encoding a plant enzyme (Bedbrook et al., 1980), the use of the Agrobacterium Ti plasmid to introduce foreign DNA into plant cells (Hernalsteens et al., 1980) and the establishment of routine plant transformation systems (Bevan, 1984; Horsch et al., 1985). It became possible to express foreign genes in plants and potentially to overexpress plant genes using cDNAs linked to strong promoters, with the aim of modifying metabolism. However, the discovery of the antisense phenomenon of plant gene silencing (van der Krol et al., 1988; Smith et al., 1988), and subsequently co‐suppression (Napoli et al., 1990; van der Krol et al., 1990), provided the most powerful and widely‐used methods for investigating the roles of specific enzymes in metabolism and plant growth. The antisense or co‐supression of gene expression, collectively known as post‐transcriptional gene silencing (PTGS), has been particularly versatile and powerful in studies of plant metabolism. With such molecular tools in place, plant metabolism became accessible to investigation and manipulation through genetic modification and dramatic progress was made in subsequent years (Stitt and Sonnewald, 1995; Herbers and Sonnewald, 1996), particularly in studies of solanaceous species (Frommer and Sonnewald, 1995).
Answer:
Membrane bound cell organelles
Explanation:
A prokaryotic cell lacks a membrane defined nucleus and all the membrane-bound organelles. A eukaryotic cell has a membrane-bound nucleus and other membrane-bound organelles such as mitochondria, chloroplasts, endoplasmic reticulum, lysosomes, Golgi apparatus, etc.
To determine if a cell is a prokaryotic or eukaryotic, one can look for the nucleus and the membrane-bound organelles. If the cell has a nucleus and membrane-bound organelles, it is a eukaryotic cell. The absence of these structures makes it a prokaryotic cell.
