▁St retch ▁marks , ▁often ▁from ▁pre gn ancy ▁and ▁ob es ity , ▁are ▁also ▁located ▁in ▁the ▁der mis . ▁ ▁Sub cut aneous ▁t issue ▁ ▁The ▁sub cut aneous ▁t issue ▁( also ▁hyp od erm is ▁and ▁sub cut is ) ▁is ▁not ▁part ▁of ▁the ▁skin , ▁but ▁lies ▁below ▁the ▁der mis ▁of ▁the ▁cut is . ▁Its ▁purpose ▁is ▁to ▁attach ▁the ▁skin ▁to ▁underlying ▁b one ▁and ▁mus cle ▁as ▁well ▁as ▁supp lying ▁it ▁with ▁blood ▁vessels ▁and ▁n erves . ▁It ▁consists ▁of ▁loose ▁connect ive ▁t issue , ▁ad ip ose ▁t issue ▁and ▁el ast in . ▁The ▁main ▁cell ▁types ▁are ▁fib ro bl asts , ▁macro ph ages ▁and ▁ad ip ocy tes ▁( sub cut aneous ▁t issue ▁contains ▁ 5 0 % ▁of ▁body ▁fat ). ▁F at ▁serves ▁as ▁padding ▁and ▁ins ulation ▁for ▁the ▁body . ▁ ▁Cross - section ▁ ▁Development ▁ ▁Sk in ▁color ▁ ▁Human ▁skin ▁shows ▁high ▁skin ▁color ▁variety ▁from ▁the ▁dark est ▁brown ▁to ▁the ▁light est ▁p ink ish - white ▁h ues . ▁Human ▁skin ▁shows ▁higher ▁variation ▁in ▁color ▁than ▁any ▁other ▁single ▁m amm al ian ▁species ▁and ▁is ▁the ▁result ▁of ▁natural ▁selection . ▁Sk in ▁p ig ment ation ▁in ▁humans ▁evol ved ▁to ▁primarily ▁reg ulate ▁the ▁amount ▁of ▁ult rav io let ▁radiation ▁( U V R ) ▁pen etr ating ▁the ▁skin , ▁cont rolling ▁its ▁bio chem ical