Final answer:
Toxoplasma gondii oocysts take approximately 1-5 days to sporulate in the environment and become infective, making the correct answer b) 5-7 days. This process is essential for the continuation of the parasite's life cycle, which can cause latent infections and is particularly dangerous for immunocompromised individuals and pregnant women.
Step-by-step explanation:
The life cycle of the protozoan Toxoplasma gondii is quite complex, involving various hosts and stages. The initial stage of the cycle begins when a definitive host, mainly domestic cats, sheds unsporulated oocysts in their feces. For these oocysts to become infectious, they must undergo a process called sporulation in the environment, which takes approximately 1-5 days. During this time, the oocysts transform and become capable of causing infection when ingested by intermediate hosts, like birds and rodents, or by accidental hosts, such as humans.
Once inside an intermediate host, the oocysts evolve into tachyzoites, which further localize in neural and muscle tissues to form tissue cyst bradyzoites. These cysts can cause a latent infection that can be reactivated, particularly in immunocompromised individuals, leading to serious health complications, including encephalitis and cognitive disorders. Pregnant women need to exercise caution as toxoplasmosis can also pose significant risks to the developing fetus.
It's crucial to note that the question specifically asks about the time frame for the oocysts to sporulate and become infectious. Therefore, the correct option is b) 5-7 days.