appendicular skeleton appendages and supporting girdles

Download Appendicular Skeleton Appendages and supporting girdles

Post on 31-Mar-2015




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Appendicular Skeleton Appendages and supporting girdles Slide 2 Slide 3 Pectoral Girdle Function Slide 4 Pectoral Girdle Replacement bones Coracoid (Epicoracoid) Scapula Suprascapula Slide 5 Slide 6 Pectoral Girdle Membrane bones Clavicle Cleithrum Supracleithrum Postcleithrum Posttemporal Interclavicle (Episternum in tetrapods) Slide 7 Slide 8 Pectoral Girdle Glenoid fossa on scapula for limb attachment Slide 9 Key Point What trend do you see as you look at the overview of pectoral girdles? Slide 10 Slide 11 Pectoral Girdle - Placoderms First to have a pectoral girdle Slide 12 Pectoral Girdle - Chondrichthyes Cartilage No dermal elements Coracoid, scapula, suprascapula (scapulacoracoid) Not connect to axial skeleton, but fused at midline Slide 13 Slide 14 Pectoral Girdle Bony fish Membrane bones Clavicle, some have interclavicle Cleithrum largest Supracleithrum, postcleithrum Posttemporal anchors to skull Slide 15 Slide 16 Pectoral girdle bony fish Replacement bones Coracoid Scapula Slide 17 Slide 18 Pectoral Girdle - amphibians Membrane bones Reduced Lose posttemporal Early amphibians gained an interclavicle as a brace Slide 19 Pectoral Girdle - amphibians Replacement bones Coracoid Scapula and suprascapula Slide 20 Slide 21 Pectoral Girdle - amphibians Urodeles have no membrane bones, including clavicle Anurans have clavicle, no interclavicle and usually no cleithrum Slide 22 Pectoral girdle - Reptiles Stem reptiles & synapsids Many membrane bones present Most replacement bones present New posterior coracoid present Slide 23 Slide 24 Pectoral girdle - Reptiles Modern reptiles have scapula, coracoid, sometimes clavicle, sometimes interclavicle Crocodiles have reduced clavicle Turtles have interclavicle fused with shell Snakes have no girdle Lizards have a significant clavicle and interclavicle Slide 25 Slide 26 Pectoral Girdle - birds Furcula (2 clavicles plus interclavicle) Scapula bladelike Coracoid (anterior or pro-) which articulates with sternum Slide 27 Slide 28 Pectoral Girdle - mammals Monotremes similar to stem reptiles Clavicle in most Scapula Coracoid process from posterior coracoid Spine is new Acromion process articulates with clavicle (not new) Slide 29 Slide 30 Slide 31 Slide 32 Slide 33 Pelvic Girdle Stability, encloses pelvic cavity organs In tetrapods, it has three parts called the ilium, pubis and ischium When these three bones fuse into one, the fused bone is the innominate or coxal bone Acetabulum is the socket for the thigh Symphysis in all but birds Replacement bone Slide 34 Slide 35 Slide 36 Pelvic Girdle - Fish Pelvic plate or symphysis Slide 37 Slide 38 Pelvic Girdle - amphibians Pubis Ilium (long & slanted in frog) Ischium Slide 39 Slide 40 Pelvic Girdle - Reptile Sacroiliac joint is stronger and broader for more muscle attachment and stability Slide 41 Slide 42 Pelvic Girdle - birds Synsacrum Ilium is braced against fused vertebrae No symphysis WHY?? Slide 43 Slide 44 Pelvic girdle - mammals Epipubic bone in marsupials is unique for pouch support Slide 45 Slide 46 FINS Steering, rolling, braking, stabilizers, forward & vertical movement Slide 47 Fin structure Skin epidermis covering Fin rays in dermis Lepidotrichia (scale-hair) bony dermal scales, segmented Ceratotrichia (horn-hair) cartilaginous unsegmented rays Slide 48 Slide 49 Fin Structure Skeletal base (cartilage or bone) for support Pterygiophores (bearing fin) Basals are proximal Radials are distal Slide 50 Slide 51 Paired Fins Absent in agnathans Some in placoderms & acanthodians Chondrichthyes Fin Fold Fins very broad based Slide 52 Slide 53 Paired Fins Bony fish Actinopterygii has ray fins, very flexible with thin base Sacrcopterygii has fleshy muscular base Dipnoi has lobe fins Crossopterygii has lobe fins that are called fringe fins & have pterygiophores on one side of fin axis Slide 54 Osteichthyes skeleton Pelvic fin Pectoral fin Caudal fin Dorsal fins Anal fin Slide 55 Slide 56 Slide 57 Slide 58 Origins of fins From acanthodian spines? From fleshy folds? From gills? Slide 59 Median fins Dorsal and Anal fins Slide 60 Dorsal and Anal Fins Function for rolling, defense, display Location rests on vertebral column Variations among groups Slide 61 Caudal fins Heterocercal Hypocercal Diphycercal Homocercal Teleosts Neural and Hemal arch for support Bony sheath for notochord Slide 62 Pelvic fin Pectoral fin Caudal fin Dorsal fins Anal fin Slide 63 Fish tails Heterocercal Homocercal Diphycercal


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