Which of the following is one of the principal purposes of the Agricultural Research Service? preventing the invasion of non-native plant species

grading the quality of plants sold as food

preserving plant species in natural environments

working on plant genomic projects

Holozoic nutrition refers to the regular animal nutrition mode whereas saprophytic nutrition refers to the nutrition mode of fungi and bacteria.

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.