Answer:
F-: StrR, his+ and met+
Explanation:
the strain Hfr is a high-frequency strain of recombination that includes the F plasmid (fertility factor). Therefore, the whole genome sequence is able to be passed via Hfr to its receiver, but it needs a long duration of physical contact with the recipient because the recipient gets a gene (long time physical contact is seldom attained) and retains the F strain. Also, genomes from the F-cells are not passed backwards to the HF cells. Therefore, only F strain with tolerance to Streptomycin and capable of synthesizing its amino acids on limited media can thrive in this situation. Which is F-: StrR, his+ and met+ recombining.
Anatomical terminology. Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream.
A food chain follows one path of energy and materials between species. A food web is more complex and is a whole system of connected food chains. In a food web, organisms are placed into different trophic levels. ... Producers are the basic trophic level while top predators are the peak level.
Populations
communities
ecosystem
biosphere
