Antigen + TH Antibody Secretion
As represented in the model above, B cells are activated by direct contact with antigens or stimulated
helper T cells (TH). Based on the model, which of the following best describes an outcome of B cell
activation?
a. Activated B cells differentiate into plasma cells and memory cells.
b. Activated B cells stimulate TH cells to secrete antibodies.
Plasma cells produce antibodies that activate additional B cells by a positive feedback
mechanism.
.. Both B cells and TH cells release chemical signals that negatively regulate
antigen-presenting cells.

Drag the correct tiles to the image. not all tiles will be used. the diagram is a schematic representation of the electron transport mechanism in mitochondria. label the diagram to complete the model.

The human genome project is devoted to mapping the general dna sequence of our species. this could lead to the development of new medicines, as well as the possibility of using gene therapy to treat certain diseases. however, there are some ethical issues surrounding the mapping of individual genomes. one concern is a) that your genes may change over time, making the project useless. b) that insurance companies could discriminate based on genetic make-up. c) that since this has never been done before, we should probably not do it now. d) that sequencing our individual genomes is so expensive, it is a counter-productive strategy.

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above