1. which of the following traits is not characteristic of animals?
multicellular body structure
composed of cells with cell walls
heterotrophic food-getting pattern
composed of eukaryotic cells
2. which of the following describes the most important difference between invertebrates and vertebrates?
vertebrates contain multiple tissues, while invertebrates do not.
invertebrates contain multiple tissues, while vertebrates do not.
vertebrates contain a backbone, while invertebrates do not.
invertebrates contain a backbone, while vertebrates do not.

1. composed of cells with cell walls
2. Vertebrates contain a backbone, while invertebrates do not.

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.

The answer would be c