Course contents
The course provides students with a solid foundation for the knowledge of Comparative Vertebrate Anatomy, based on embryonic development and on the phenomena of adaptation to the environment seen in an evolutionary key.
The following topics are covered:
§ The Protochordates and origin of Vertebrates (or Emicephalochordates or Craniotes; Phylogenetic and general anatomical features aspects (bauplan), centralization, regionalization of anteroposterior axis and genetic control of development (homeotic Hox genes), metamerism and bilateral symmetry, planes and anatomical axes, characterizing structures: notochord, skull, vertebrae, central nervous system, pharynx, body cavities.
§ Basic concepts: analogy, homology, homoplasy, rudimentary and vestigial structures, divergence, parallelism, convergence, ontogeny, phylogeny, von Baer law (evo-devo and phylotypic stage), cladistics (mono-, para-, poliphyletism), archetypes and living fossils.
§ Classification, general characteristics and phylogenetic relationships among the major taxa of Vertebrates; AGNATES (Ostracoderms and Cyclostomes) and GNATHOSTOMES (Placoderms, Chondrichthyes, Acanthodians, Osteichthyes, Labyrinthodonts, Amphibians, Cotilosaurian, Reptiles, Archaeornites, Birds, Therapsids, Mammals).
§ The ontogeny of Cephalochordata and Vertebrates; gametogenesis, types of eggs and associated membranes, segmentation, gastrulation of coeloblastulae (Amphioxus, Fishes, Amphibians) and discoblastulae (Fish, Sauropsidae and Mammals), neurulation, derivatives of the three germ layers (ecto-, meso-, endoderm), neural crests as the fourth germ layer, somatic and germ components, induction, direct and indirect development (larval stage), oviparity-ovoviviparity-viviparity, fetal membranes (yolk sac, albumen sac, amnios, chorion, allantois, placentas) , the regenerative capabilities of Vertebrates.
§ Skeletal system; a) Types of skeletal tissue (cartilage, bone) and scheletogenous blastema (somites, somitomeri, neural crest, the skeletogenous septa system, etc.), direct or membranous ossification (allostosis) and indirect or endochondral (autostosis). b) axial skeleton: notochord, vertebrae (genesis, acentric and centric vertebrae, diplo- and monospondilia, arcocentric and cordocentric, amphi-, pro-, opisto-, eterocelic, amphyplanar vertebrae), regionalization of the spinal chord, ribs, abdominal ribs (gastralia) , sternum, skull [cranium (platibasia, tropibasia), splanchnocranium, dermatocranium (anapsides, diapsides, sinapsides, parapsides, primary and secondary palate), autostilic, anfistilic, iostilic suspensions, cranial cinetism]. c) zonal skeleton: pectoral girdle, pelvic girdle (saurischian and ornitischian), etc .. d) appendicular skeleton: unpaired and paired fins, chiridium limb and adaptation to locomotion (running, jumping, flying, swimming). e) heterotopic bones.
§ Integumentary system: general organization, embryonal derivation, dermal-epidermal interaction, epidermis and its derivatives (glands, photophores, scales, feathers, hair, beaks, claws, nails, hooves, horns), dermis and its derivatives [bony scales (cosmoid , placoid, ganoid, elasmoid, cycloid, ctenoid) and their phylogenetic relationships, osteoderms, etc., sensory receptors, pigmentary cells (xantofores, iridofores, melanophores, melanocytes, cromatophora units).
§ Digestive System; stomodeum and proctodeum, mouth and oral cavity, salivary glands, teeth (genesis and classification), tongue, microanatomical organization of the intestinal wall, pharynx and its derivatives, esophagus and craw, glandular and muscular stomach, pre-stomach (gastric fermentation), small intestine and pyloric blind cavities, large intestine and blind ileocholic cavities (intestinal fermentation), liver, pancreas.
§ Respiratory system; gill respiration (external gills, internal gills: pouch-like gills, septed gills and comb-like gills, counterflow gas exchange, pseudo-gills, cutaneous and pulmonary respiration, saccular lungs, natatory bladder, lung parenchymal, aeriferous sacs, respiratory tract, body cavity and its distribution.
§ Circulatory system; microanatomical organization of the wall of blood and lymph vessels, blood and emopoiestic / emocatheretic organs, types of circulation (single/double, open/closed, incomplete/complete), genesis and evolution of the heart, the heart and aortic arches of fish with simple and double circulation (Dipnoans), heart and aortic arches of Aamphibians (larval/adult stage), the heart and aortic arches of Reptiles (squamated/loricates), heart and aortic arches of Birds and Mammals, vascularization of brain, Willis circle, embryonic movement of anamniotes and amniotes, main arteries and veins, portal systems (kidney, liver, pituitary).
§ Urogenital; a) osmoregulator and excretory organs, pronephros, mesonephros (opistonephros), metanephros, nephronic vascularization, urinary tract and bladder, chlorides cells of Fishes, rectal gland of Elasmobranchs, salt glands of Sauropsida, nitrogen catabolism (ammoniotelia, ureotelia, uricotelia). b) Genesis of the gonads (genital ridges): somatic and germ components, cystic and tubular testicles, medullo-Wolffian interaction, cavitated and parenchymal ovaries, oviducts and their specializations, cloaca: derivatives (spermatheca, bursa of Fabricius, urinary bladder, copulatory organs , etc.) and its partitions, urinary bladder.
§ Nervous system and sense organs; a) SNC: telencephalon, rhinencephalon and cerebral hemispheres (paleo-, archi-, neo-cortex), diencephalon (epithalamus, thalamus, hypothalamus, neurohypophysis, epiphysis, optic chiasm), midbrain (optic lobes), hindbrain (cerebellum: archi-, paleo -, neo-cerebellum), myelencephalon, spinal cord, cranial nerves. b) nasal olfactory epithelium, vomero-nasal organ (or Jacobson), eye and photoreception, inner, middle and external ear, lateral line system.
§ Endocrine Organs; neurosecretion and pituitary gland, chromaffin tissue and adrenal medulla, interrenal tissue and adrenal cortex, the interstitial cells of the gonads, endostylum and thyroid, parathyroid and ultimobranchial bodies.
In addition to the lectures, practical exercises consisting in the microscope recognition of embryonic structures of anamnes and amniotes are carried out.