Haversian canals (also called central canals) run longitudinally through the bone and contain blood vessels and nerves which supply the bone.
Business casual: Generally means khaki pants, a plain polo shirt or a long-sleeved casual button-down oxford shirt, a V-neck sweater, sometimes a sports coat or blazer, and brown leather shoes. Loafers are a good choice, and you should wear socks.
Business casual is a shirt and pants! From VA Tech website: Specifics for men's business casual Ties: Ties are generally not necessary for business casual, but if you are in doubt, you can wear a tie. It never hurts to slightly overdress; by dressing nicely, you pay a compliment to your host.