Plasmid is a small, circular, double-stranded DNA molecule that is distinct from a cell's chromosomal DNA. Plasmids naturally exists in bacterial cells, and they also occur in some eukaryotes. The genes carried in plasmids provide bacteria bacteria with genetic advantages, such as antibiotic resistance. To know whether the cell carry recombinant plasmids; only cells with a plasmid will reproduce and also the color of the colonies in E. coli plasmid recombination experiments allows scientists to distinguish colonies with recombinant plasmids from those without.
Answer:
The answer is option D "Machines have replaced much of the manual labor once needed to run a farm."
Explanation:
* Progress in Engineering: This simply means how technological machines like heavy tractors which are now used and are helpful in farming are evolving, meaning they are being used in a larger quantity now.
* Natural Environment: This is the normal way of life or doing things which individuals find themselves practicing in a particular society and at a particular point in time.
* As a result of the machines being developed as an Engineering progress which serves the work of people on the farms, there tends to be less manual labor that would be initially required to run a farm. The machines are now serving the work of human beings (laborers) now.
Carbon monoxide is the most common type of poisoning by gases
Answer:
Explanation:
The near-surface open water surrounded by the littoral zone is the limnetic zone. The limnetic zone is well-lighted (like the littoral zone) and is dominated by plankton, both phytoplankton and zooplankton. Plankton are small organisms that play a crucial role in the food chain.
