Develop in two phases: (1) blood vessels in the brain narrow, so that the flow of blood to parts of the brain is reduced, and (2) the same blood vessels later expand, so that blood flows through them rapidly, stimulating many neuron endings and causing pain.

The answer for the question is Migraine. Migraines Headaches are extremely, nearly paralyzing headaches that are located on one side of the head and are sometimes accompanied by dizziness, nausea, or vomiting. They normally develop in two phases; The first phase, in which blood vessels in the brain narrow (vasocontsriction), such that the flow of blood to arts of the brain is reduced. Second phase; occurs when the blood vessels expand, such that blood flows through them rapidly, thus stimulating many neuron endings and causing pain.

The answer is a i believe

If you remove all the lions from the savanna it will lead to a increase of gazelle and a increase of cheetahs becasue of no competition