seizure Period of lost consciousness that may include violent muscle contractions.
stimulant drug Psychoactive drug that speeds up the nervous system.
tension headache Headache that occurs when muscles in shoulders, neck, and head be-
come too tense.
tolerance Condition in which people need to take more of a drug to feel the same effects
as when they first started using the drug.
tumor Mass of cells that grow out of control; associated with cancer.
withdrawal Symptoms like vomiting, diarrhea, or depression that can occur when people
stop using a drug.
Points to Consider
- Although the nervous system controls the body, it doesn’t do it alone. It gets help
from another body system, called the endocrine system. This is a system of glands
that secrete hormones. Hormones are chemicals released by cells that affect cells in
other parts of the body. - Think of how hormones can help control body processes?
Image Sources
(1) http://en.wikipedia.org/wiki/File:Chocolate02.jpg
http://en.wikipedia.org/wiki/Image:Generic_Cola_Can_Jewel.jpg.
(c)CC-BY-SA, GNU-FDL.(2) http://us.fotolia.com/id/6182002. Royalty Free.(3) http://commons.wikimedia.org/wiki/File:Plastic_beads1.jpg. CC-BY.(4).(5) http://www.benet.org/teachers/meraci/ReflexArcWithoutLabels.jpg.(6) [Dreamstime.com ]. Royalty Free.