So here we have an example problem that wants us to number the following steps of the plasmodium life cycle so that they are in the correct order starting from when a mosquito bites and infects a human. Notice below, we've got these 7 bulleted steps that we need to properly order by filling in the numbers in these blanks. Given that the first step starts with an infected mosquito biting a human, infecting it with the sporozoite form of the plasmodium parasite, this is our starting point. Recall from our previous lesson videos that these sporozoites go on to infect the human liver cells.

The step below states that sporozoites infect human liver cells. Then, those sporozoites become merozoites and reproduce asexually until the merozoites are released from the liver into the blood. This is step number 2. Recall that these released merozoites in the blood go on to continuously infect and destroy red blood cells. Notice the step below says that merozoites continuously infect and destroy red blood cells as they reproduce asexually, forming more merozoites and causing further infection and destruction of red blood cells.

This process is what causes the symptoms associated with malaria, such as fever and chills, marking it as step number 3. Some merozoites will differentiate into plasmodium gametocytes, which is step number 4.

These gametocytes can form gametes, but only inside a mosquito. Therefore, the gametocytes need to make their way back to a mosquito, and the next step involves an uninfected mosquito biting this infected human and picking up the plasmodium gametocytes from step number 4, which is step number 5. From there, the gametocytes can produce gametes.

The step stating that gametocytes form gametes that then fertilize inside the mosquito's digestive tract, forming a diploid zygote, is step number 6. The final step, step number 7, involves the zygote undergoing meiosis then mitosis, releasing haploid sporozoites into the mosquito's salivary gland, thus completing the cycle so that step number 1 can occur again.

This concludes this example problem, and I'll see you all in our next video.