12/20 is the answer I think. I hope this helps you!!
In general, Yes True <span />
Answer:
E. It takes a picture of the brain according to oxygen levels. More oxygen in an area indicates more activity in that area.
Explanation:
Haemoglobin is diamagnetic when oxygenated but paramagnetic when deoxygenated. This distinction in magnetic characteristics leads to tiny variations in the blood MR signal. Since blood oxygenation differs, these variations can be used to identify brain activity depending on the concentrations of neural activity.
Natural selection can cause speciation, which increases the biodiversity of an ecosystem. Several bacterial colonies are placed on a petri dish that contains agar with antibiotics. After 24 hours, ninety percent of the original bacteria die, but the remaining ten percent survive and later reproduce.
