In a larger city you have the risk of being in danger more than in a small town because it more busy and has alot more going on which makes it harder to be physical active without getting hit by a car or someone walk or riding a bike.
They produce sperm and they secrete hormones (testosterone)
Meninges- three layers of connective tissue
1) Dura Mater: tough top layer
2) Arachnoid Mater: middle; collagen/elastic fibers; spiderweb effect
3) Pia Mater: delicate and thin; bottom transparent layer made up of elastic/collagen fibers; blood vessels
B. Red blood cells contain a protein that binds with oxygen.