SUMMARY(anat14)

Respiratory system 呼吸器系  
 

 1. Gill

    --- Embryonal development of all vertebrates

               --- Lateral wall of pharynx

    --- Anatomical position
          --- Within opercular cavity\ gill chamber\ branchial cavity
 

    --- Respiratory and excretory functions

          --- a. Respiration

                   --- Extraction of O₂ \ Excretion of CO₂
 

                   --- Other respiratory tissues

                         --- Skin\ Yolk sac\ Fins\ Gill covers

               b. Excretion
 

                   (a) Nitrogenous metabolic wastes
                   (b) Exchange of univalent ions

    1) Path of the respiratory water

        --- a. Teleosts

             b. Holocephali

             c. Elasmobranchii

    2) Internal gill

--- A double row on each bone
 

        (1) Gill arches
 

              --- 5 pairs in left and right side in osteichthyes

                    --- 6∼7 pairs in some chondricthyes

        (2) Gill raker (Branchictenia, 새파)

              --- No gill rakers in certain fish 

              --- Located on the medial lining of branchial arches

              --- Primary and secondary raker

              --- Functions of gill raker

                  a. Mastication\ Aqusition of foods

                   b. Protection of gill filaments

       (3) Gill filaments

             --- No filaments in the last arch of osteichthyes

             a. Primary lamellae or filaments

                  --- Arrangement in a double-row on each bone

             b. Secondary lamella or Lamellae branchiales

     2) Pseudogill or pseudobranch

         --- No pseudobranch in anguilliformes

         --- Separate gill located on the medial surface of the opercle or on the anterior wall of

              hyomandibular cleft

               --- No respiratory function/A few secondary lamella

        --- 3 types of pseudobranchs (Birtin's differentiation)

             (1) Free type

             (2) Covered type

             (3) Embedded or submerged type (Cypriniformes)

    3) Interbranchial septum(Gill septum)

        --- Between anterior and posterior filaments of each branchial arch

               --- a. Well-developed interbranchial septum

                    b. Regressive interbranchial septum

   4) External gill

        --- During the early development stages of some species,  ie., embryonic or larval organs

         --- Function

              --- a. Respiratory

                       --- Often not exclusively

                   b. Nourishing the embryo

                       --- (a) From yolk of the egg

                            (b) From special uterine secretions in live-bearing species

 2. Accessory respiratory organs

    1) Organs of aquatic respiration

        --- Young fishes during the gillless phase

              --- a. Skin or body surface
                   b. Primordial fin

                      <--- A thin fold of skin

                   c. Gill cover in holocephali

                   d. Vascular network which develops around the yolk sac in embryos and larvae

    2) Air-breathing organs

       a. Lung(Dipnoi\ Polypteryformes)

            --- A primitive type similar to that which existed when the lungs and swimbladders first began to

                 evolve

                  ---> ① Teleostean swimbladder

                        ② Tetrapod's lung

            --- Dipnoan lung

                  --- Not very efficient in the excretion of CO₂, even in recent dipnoi

            --- Electric eels (Electrophorus electricus) 

                  --- The oral cavity(From the air)

                         --- Taking-up only 78% of the oxygen which the body requires

                         --- 81% of the CO₂ releasing into the water through the skin

       b. Swimbladder

            --- Never developed in the agnatha\ the lower gnasthomata, ie., the elasmobranchii and the

                 holocephali

       c. Oral and branchial cavities

       d. Gill-appendages\ Branchial papillae\ Special labyrinthine organs

       e. Stomach\ Intestine

   [Vasculature of the gill]

    --- 2 kinds of vasculatures

          --- a. Respiratory blood pathway

              b. Non-respiratory blood pathway

   1) Respiratory blood vasculature

        --- Ventral aorta
               --->Dorsal aorta

    2) Non-respiratory blood pathway
 

         --- Efferent branchial artery (or efferent filamental artery)

               ---> Along the long axis of filament

                       ---> Branchial vein (Nutrient vasculature)
 

SUMMARY(anat14)