The activation of helper T cells is likely Group of answer choices in the bone marrow during the self-tolerance test. when an antigen is displayed by a dendritic cell. when B cells respond to T -independent antigens. when natural killer (NK) cells come in contact with a tumor cell. when a cytotoxic T cell releases cytokines.

Plz ! a scientist wants to produce a cow that makes a particular human protein in it’s milk the desired protein causes blood to clot and can be used to treat hemophilia (a blood clotting disorder). which of the following would be best for the scientist to use? a. genetic crosses. b. cloning. c. selective breeding. d. genetic engineering.

What causes darkening of the skin as melanin production increases

Explain why the plants cortex would serve as the best food source for animals