▁frat ern ities ▁and ▁sor or ities ▁soon ▁established ▁chap ters ▁at ▁the ▁university , ▁although ▁they ▁presented ▁themselves ▁as ▁service ▁organizations ▁rather ▁than ▁traditional ▁social ▁organizations . ▁In ▁the ▁mid - 1 9 7 0 s , ▁although ▁some ▁black ▁students ▁were ▁invited ▁to ▁join ▁the ▁heavily ▁white ▁frat ern ities , ▁many ▁preferred ▁to ▁join ▁their ▁own ▁organizations . ▁By ▁the ▁fall ▁of ▁ 1 9 7 3 , ▁four ▁black ▁frat ern ities , ▁the ▁L ambda ▁Z eta ▁chapter ▁of ▁Om ega ▁P si ▁Ph i ▁( Ω Ψ Φ ), ▁the ▁E ta ▁S igma ▁chapter ▁of ▁K appa ▁Al pha ▁P si ▁( Κ Α Ψ ), ▁the ▁I ota ▁B eta ▁chapter ▁of ▁Al pha ▁Ph i ▁Al pha ▁( Α Φ Α ), ▁and ▁the ▁Z eta ▁E ta ▁chapter ▁of ▁Ph i ▁B eta ▁S igma ▁( Φ Β Σ ), ▁and ▁one ▁black ▁sor or ity , ▁K appa ▁R ho ▁( Κ Ρ ) ▁chapter ▁of ▁D elta ▁S igma ▁Th eta ▁( Δ Ζ Θ ), ▁had ▁established ▁chap ters ▁on ▁grounds . ▁ ▁Women ' s ▁organizations ▁In ▁ 1 9 7 0 ▁the ▁College ▁of ▁Arts ▁and ▁Sciences ▁allowed ▁the ▁first ▁women ▁to ▁en roll ▁in ▁its ▁under grad uate ▁programs , ▁which ▁effectively ▁made ▁the ▁university ▁co ed uc ational . ▁This ▁led ▁to ▁the ▁rapid ▁establishment ▁of ▁many ▁social ▁sor or ities ▁at ▁the ▁university , ▁and ▁by ▁the ▁end ▁of ▁the ▁ 1 9 7 0