AP Biology 4.3.A Cellular Responses to Signaling
Practise AP Biology 4.3.A questions by connecting signal transduction with gene expression, cell function, differentiation and programmed cell death.
- Syllabus
- Effective Fall 2025
- Course
- AP Biology
Practise AP Biology 4.3.A questions by connecting signal transduction with gene expression, cell function, differentiation and programmed cell death.

B-cell activation model
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?
Activated B cells differentiate into plasma cells and memory cells.
Activated B cells stimulate TH cells to secrete antibodies.
Both B cells and TH cells release chemical signals that negatively regulate antigen-presenting cells.
Plasma cells produce antibodies that activate additional B cells by a positive feedback mechanism.
A