Given a scientific passage and an answer, generate a question for the given answer.

[EX Q]: Passage: Infectious diseases are diseases that spread from person to person. They are caused by pathogens such as bacteria, viruses or fungi. What can you do to avoid infectious diseases? Eating right and getting plenty of sleep are a good start. These habits will help keep your immune system healthy. With a healthy immune system, you will be able to fight off many pathogens. The next best way is to avoid pathogens. Though this is difficult, there are steps you can take to limit your exposure to pathogens. Answer: immune system
[EX A]: What system is responsible for defending your body against sickness?

[EX Q]: Passage: The wide range of movement allowed by synovial joints produces different types of movements. Angular movements are produced when the angle between the bones of a joint changes. Flexion, or bending, occurs when the angle between the bones decreases. Moving the forearm upward at the elbow is an example of flexion. Extension is the opposite of flexion in that the angle between the bones of a joint increases. Rotational movement is the movement of a bone as it rotates around its own longitudinal axis. Movement of the head as in saying "no" is an example of rotation. Answer: angular
[EX A]: What type of movements are produced when the angle between the bones of a joint changes?

[EX Q]: Passage: Fertilization occurs when an egg and sperm come together to form a zygote. Answer: zygote
[EX A]:
Fertilization occurs when an egg and sperm come together to form a what?