Module 4: Avian Respiratory System

• birds airflow is described as

  unidirectional
• air moving through birds lung is mainly

  fresh air; high oxygen content
• mammalian airflow is described as

  bidirectional
• only _ is for gas exchange while _ is for air flow

  lungs; air sac
• avian air sacs act as _ to ventilate air

  bellows
• avian air sacs are(vascularity)

  avascular
• how many air sacs do avians have

  9
• makes up anterior air sacs

  2 cervical; 1 clavicular; 2 cranial thoracic
• makes up posterior air sac

  2 caudal thoracic; 2 abdominal
• only unpaired air sac

  clavicular
• if only 7 air sacs are present, what is absent

  2 cervical
• if only 8 air sacs are present, what is absent

  1 clavicular
• avian lungs are (compliancy)

  noncompliant
• unique structure among birds

  syrinx
• connection between humerus and air sac

  diverticuli
• avian larynx has no _

  voice box
• regarded as avian organ of phonation

  syrinx
• syrinx is located before

  bifurcation of trachea
• birds do not have

  diaphragm
• how many phases of respiration cycles do avians have

  4
• birds only have a _ (pharynx)

  oropharynx
• thoraco abdominal cavity is an _ that separates the 2 cavities

  aponeurosis
• bronchi directly supplying air to posterior air sacs

  primary
• bronchi directly supplying air to anterior air sacs

  secondary
• bronchi directly involved in gas exchange

  tertiary/parabronchi
• 2 types of parabronchi

  paleopulmonic, neopulmonic
• parabronchi involved in gas exchange

  paleopulmonic
• parabronchi that is interconnected into a meshwork that covers lateral surface of lungs

  neopulmonic
• neopulmonic parabronchi is not present in

  penguin, emu
• gas exchange occurs in what capillaries

  air, blood
• air moves from external environment into posterior air sacs

  first inhalation
• air moves from posterior air sacs into lungs

  first exhalation
• air moves from lungs to anterior air sacs

  second inhalation
• air moves from anterior air sacs to external environment

  second exhalation
• air in first inhalation is considered

  fresh
• air in second inhalation is considered

  deoxygenated
• 3 major respiratory centers

  dorsal respiratory group, ventral respiratory group, pneumotaxic center
• special center responsible for increasing depth of inspiration and causes delay in switch off of inspiratory ramp

  apneustic center
• alternation of inspiratory ramp in seconds

  2 inspiration, 3 expiration
• dorsal respiratory group mainly causes

  inspiration