Editing Bronchus (section)

{{short description|Airway in the respiratory tract}}
{{Infobox anatomy
| Name        = Bronchus
| Latin       = bronchus
| Greek      = βρόγχος
| Image       = 3D Medical Animation Bronchus Description.jpg
| Caption     = The bronchi are conducting passages for air into the lungs.
| Image2      = Blausen 0770 RespiratorySystem 02.png
| Caption2    = The bronchi form part of the [[lower respiratory tract]]
| Precursor   =
| System      = [[Respiratory system]]
| Artery      = [[Bronchial artery]]
| Vein        = [[Bronchial vein]]
| Nerve       = [[Pulmonary branches of vagus nerve]]
| Lymph       =
}}
A '''bronchus''' ({{IPAc-en|ˈ|b|ɹ|ɒ|ŋ|k|ə|s}} {{respell|BRONG|kəs}}; {{plural form}}: '''bronchi''', {{IPAc-en|ˈ|b|ɹ|ɒ|ŋ|k|aɪ}} {{respell|BRONG|ky}}) is a passage or airway in the [[lower respiratory tract]] that conducts [[Atmosphere of Earth|air]] into the [[lung]]s. The first or primary bronchi to branch from the [[trachea]] at the [[Carina of trachea|carina]] are the right main bronchus and the left main bronchus. These are the widest bronchi, and enter the right lung, and the left lung at each [[Root of the lung|hilum]]. The main bronchi branch into narrower secondary bronchi or lobar bronchi, and these branch into narrower tertiary bronchi or segmental bronchi. Further divisions of the segmental bronchi are known as 4th order, 5th order, and 6th order segmental bronchi, or grouped together as subsegmental bronchi.<ref name="Netter">{{cite book|last1=Netter|first1=Frank H.|title=Atlas of Human Anatomy Including Student Consult Interactive Ancillaries and Guides.|date=2014|publisher=W B Saunders Co|location=Philadelphia, Penn.|isbn=978-1-4557-0418-7|page=200|edition=6th}}</ref><ref>{{Cite book|last=Maton|first=Anthea|author2=Jean Hopkins|author3=Charles William McLaughlin|author4=Susan Johnson|author5=Maryanna Quon Warner|author6=David LaHart|author7=Jill D. Wright|title=Human Biology and Health|publisher=Prentice Hall|year=1993|location=wood Cliffs, New Jersey, USA|url=https://archive.org/details/humanbiologyheal00scho|isbn=0-13-981176-1|url-access=registration}}{{Page needed|date=September 2010}}</ref>
The bronchi, when too narrow to be supported by cartilage, are known as [[bronchiole]]s. No [[gas exchange]] takes place in the bronchi.