Week 6 of Lecture Notes
Week 6 of Lecture Notes BIOL 3020-001
Popular in Comparative Anatomy of the Vertebrates
verified elite notetaker
Popular in Biology
This 6 page Class Notes was uploaded by Maria Martinez on Friday October 2, 2015. The Class Notes belongs to BIOL 3020-001 at Middle Tennessee State University taught by Dr. Miller in Fall 2015. Since its upload, it has received 56 views. For similar materials see Comparative Anatomy of the Vertebrates in Biology at Middle Tennessee State University.
Reviews for Week 6 of Lecture Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/02/15
Week 6 Lecture Notes Biology 3020 Neurocranium Several prominent preskeletal blastomae that develop into occipital parachordal precorta sense organs optic olfactory Ossification Centers Where bone develops Within cartilage Blood vessels carry osteoblast in cartilage and that forms the bone 4 Groups of ossification centers 1 Occipital centers Supraoccipital on top Exoccipital on the sides Basioccipital on the bottom as they enlarge they grow toward one another and it Will for 4 distinct bones 2 Sphenoid Center develops the basisphenoid and the presphenoid 3 Ethnoid Center there isn t a lot of bones that develop here as the cartilage tends to remain cartilage here 4 Optic Center a lot of inner bones are developed here 3 main bones prootic opisthotic epiotic One or more of these may unite with adjacent replacement or membrane bones Frogs and most reptiles opisthotics fuse with exoccipitals Birds and mammals prootic opisthotic amp epiotic unite to form a single petrosal bone the petrosal in turn sometimes fuses with the squamosal to form the temporal bone Dermatocranium originates as dermal bone has 4 basic regions 1 Roofing Bones form above and along the neurocranium has four associated regions 1 snout nasals 2 orbits lacrimal post orbitals 3 vault frontal parietals 4 temporal squamosal bone 2 Dermal Bones and Upper Jaw premaxilla links anterior jaw to the skull maxilla links posterior jaw to the skull a11 mammals have a dentary squamosal jaw joint this is the bone that can identify a mammal 3 Primary Palate any palate can bare teeth VOIIlCI39 palatine bones parasphenoid pterydoids become obscured by the formation of the secondary palate mammals have all 4 regions but tetrapods only have the first three Jaw Suspensions Palaestyly Jaw Found in Agnathans ancient don t have any support of jaws to brain case not jawed none of the arches attaches themselves directly to the skull Euaultostyly Jaw Found in placoderms and acanthodians The mandibular arch is suspended from the skull by itself without help from the hyoid arch Hyostyly Jaw Found in the modern day shark The mandibular arch is attached through the hyomandibula Modified Hyostyly Jaw The sympletic bone helps in the suspension Metautostyly Jaw Mostly found in reptiles birds amphibians and turtles Jaws are attached to the braincase directly through the quardrate They hyomandibula plays no part in the supporting the jaws but actually becomes the stapes and allows hearing while the hyoid supports the tongue Craniostyly Jaw Found in mammals the entire upper jaw is incorporated into the braincase while the lower jaw is suspended from the squamosal bone the lower is suspended from the dentary bone the quadrate bone becomes the incus the articular bone becomes the mallus the columella bones becomes the stapes these three bones will fuse to join up with a singular jaw bone Axial skeleton Vertebrae 2 major components 1 Neural arch significant because it helps protect spinal cord 2 Centrum replaces the notochord function in most groups of fish the centrum were concave amphicoelus means double cavity this allows for exibility as the notochord is exposed in between creating ball on socket like structure sharks proceolus means one end of the central is a cavity and the other is a disc they are concave anteriorly and convex posteriorly reptiles opisthocoelus means that the posterior end is a cavity while the anterior is a disc concave posteriorly and convex anteriorly other types of reptiles both the proceolus and the opisthocoelus allow for stretching or bending without bending the actual spinal cord Aceolus centra are at they seem well suited to receive and distribute pressure most mammals Heteroceolus means that the central have different shaped cavities and allow for lateral and vertical exion but prevent the rotation of the vertebral column turtles that retract their neck and bird s cervical vertebrae Diplasioceolus means it has more than one of the centra types in the vertebral column a lot of the vertebra but specifically a bird and some mammals There are transverse processes any process extending from the centrum or the neural arch on both sides of the neural spines The intracentra skeletal elements develop between the central and are more commonly found in the mammal or the reptilian tail Intervertebral disc has 2 major components 1 outer fibrous 2 inner more gelatinous also known as the nucleus pulposus nuclear pulp is the remnants of the notochord Hemal arches extend on the underside of the central found in the caudal vertebrae tails surrounds caudal vessels and helps protect them Anamniotes fish and amphibians Vertebral column is highly variable particularly to the centra Hagfish unconstricted notochord no centra no neural arch Lamprae Unconstricted notochord no central but some do have a neural arches that rest on the notochord Sharks Have well developed hemal arches and neural arches Have well developed amphicoelus centra Bony fish lungfish paddlefish stergens are all highly cartilaginous fish have a notochord but no central have neural and hemal arches More Advanced Bony Fish tetrapods Have well developed hemal and neural arches as well as centra Amphibians Have well developed vertebrae hemal and neural arches and centra
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'