CAS BI 106 Study Guide - Midterm Guide: Foramen Magnum, Dura Mater, Pia Mater

• School: Boston University
• Department: Biology
• Course: CAS BI 106
• Professor: Dale Pasino

Document Summary

Not the size, but the number of synapses that determines intelligence. Skull limits brain size, so our brain is folded (gyri- singular gyrus) to make room for more neurons. As (cid:449)e gro(cid:449), (cid:449)e lose (cid:374)euro(cid:374)s, a(cid:374)d the(cid:455)(cid:859)re re(cid:373)o(cid:448)ed as (cid:449)e gro(cid:449) to (cid:373)ake our (cid:271)rai(cid:374)s (cid:373)ore effi(cid:272)ie(cid:374)t. the (cid:373)ore (cid:449)e lear(cid:374), (cid:455)ou(cid:859)re (cid:373)aki(cid:374)g ph(cid:455)si(cid:272)al (cid:272)ha(cid:374)ges i(cid:374) (cid:455)our (cid:271)rai(cid:374), (cid:449)ith patterns and connections etc. Number of neurons decrease by 50% from infancy to puberty. Sulci (singular- sulcus) are grooves between gyri, deep sulci ae called fissures. As neuron cells are decreasing in number, glial cells increase by 33% during development. Brain is supported and protected by connective tissue layers called meninges. Deep to superficial: pia mater (deep) arachnoid (superficial) dura mater (between)= has 2 layers- periosteal and meningeal (close to inner surface of skull) Dura is made of dense connective tissue- and you cannot see the brain beneath it. If we peal it off, then you can see brain with arachnoid.