The container, or housing, also has a membrane at {HEAD ~ an opening} thereof which is permeable to {TAIL ~ oxygen} 
The container , or housing , also has a membrane at { HEAD ~ an opening } thereof which is permeable to { TAIL ~ oxygen }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL