In a temperate region just north of the u. s.-mexico border, environmentalists observe a recent influx of aphids into grasslands, forests, and agricultural landfills. these sap-sucking insects are known to transmit plant viruses and are destructive to many cultivated plants. (a) predict the effect that this influx of aphids will have on producers in the area. (b) discuss how the influx of aphids can affect the other trophic levels of the ecosystem. write your response below.

The answers are as follows: 
a. The producers in the area are the plants, which use the energy from the sun to produce their own food. The producers are the primary source of food for the animals in the ecosystem and anything that affect them negatively will eventually affect the animals in the ecosystem too. The influx of the aphid into the area will inflict viral diseases on the plants and many of the plant will be destroyed as a result of the disease.
b. The plants, which are the producers in any ecosystem serves as the occupier of the first trophic level. Energy obtained from the first trophic level is passed down to the rest of the trophic levels for their survival. An influx of aphid into the ecosystem will destroy the plants which occur the first trophic level and this will cut off the source of food for all the other trophic level in the ecosystem. This will eventually lead to the death of all the living organisms in the ecosystem.

answer: - b cells

explanation: -

there are many types of white blood cells present in our body. one such class of white blood cells are the lymphocytes. the b cells belong to the lymphocyte class of wbcs. the b cells perform their action against the pathogen by producing specialised proteins called as antibodies. these antibodies are produced as and when the b cells encounter pathogens in response to the antigens present on the surface of the pathogen. these antibodies bind to the antigens present on the pathogen and then, target them for destruction by other cells of the immune system.

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.