A 6-year-old boy has difficulty rising from the floor without using his hands and walks with a waddling gait. What is the most likely underlying condition? 

A 50-year-old male is undergoing chemotherapy that targets rapidly dividing cells by disrupting DNA replication.  Which phase of the cell cycle is primarily affected by this treatment? 

Which cytokines are commonly produced by Th1 cells to promote cell-mediated immunity? 

A 45-year-old male with melanoma is found to have high levels of PD-L1 expression on tumor cells.  How does PD-L1 expression contribute to cancer progression? 

A patient receives a vaccine that induces a strong Tfh cell response. What is the expected outcome of this response? 

A 40-year-old female with a history of radiation exposure presents with a tumor. Her cells show an inability to arrest the cell cycle in response to DNA damage.  Which checkpoint is most likely defective in her cells? 

How do oncogenes contribute to cancer development? 

A patient with a compromised thymus gland is likely to have deficiencies in which type of immune cells? 

How can cancer-causing viruses contribute to cancer development? 

A patient suffers a cut on their arm, leading to tissue injury. Which cells are first to respond to this injury?