Lecture 2: Scales, Skin, & Skeleton

Created by

Videl Obenhin

Cards (109)

What groups of fish have a notochord?
Amphioxus
Agnathans
Chondrichthyes
Dipnoi
Acipenseridae
Polyodontidae
Latimeriidae
What are some important details about the notochord?
It is composed of cells with large vacuoles
Turgor pressure allows it to be rigid and stable
It is surrounded by a perichord
Perichord: Fibrous sheath surrounding notochord
What composes cartilage?
Chondrocytes
Extracellular Matrix
Perichondrium
Chondroblasts
Chondrocytes: Cells within the extracellular matrix of cartilage
Extracellular Matrix: Matrix that composes cartilage and that is made of collagen and chondroitin sulfate
Perichondrium: Fiberous sheath that surrounds cartilage and houses chondroblasts
Chondroblasts: Cartilage cells embedded in the perichondrium that produce new matrix
What is notable about cartilage?
It forms the early skeleton for all fishes and remains a primary endoskeletal element in others
What is different about the cartilage of a gnathostome and an agnathan?
Agnathans have smaller chondrocytes
Agnathans have a higher volume of matrix
Tessellated Cartilage: Cartilage that is made of plates of tesserae and that forms a sheath around hyaline cartilage
Tesserae: Plates of mineralized cartilage
What replaces cartilage as a bony fish matures?
Bone
Osteocyte: Main cell in bone that is embedded in matrix
In what direction does perichondrially ossifying endoskeletal bone ossify?
From the outside
In what direction does endochondrally ossifying endoskeletal bone ossify?
From the inside
What is the main component of exoskeletal bone?
Hydroxyapetite
What are the two cranial skeletal groups to know?
Chondrocranium
Branchiocranium
What group of fish lack a dermatocranium?
Agnathans
What are the four regions of the Neurocranium?
Ethmoid
Orbital
Otic
Basicranial
What bones comprise the ethmoid region of the neurocranium?
Ethmoids
Paraethmoids
Volmer
Nasals
What bones comprise the orbital region of the neurocranium?
Pterosphenoid
Basisphenoid
Sclerotic
Circumorbitals
Frontals
What bones comprise the otic regions of the neurocranium?
Sphenotic
Prootic
Pterotic
Intercalar
Epiotic
Parietal
What bones make up the basicranial region of the neurocranium?
Exoccipital
Supraoccipital
Basioccipital
Parasphenoid
What sub groups make up the Branchiocranium of a fish skull?
Splanchnocranium
Deratocranium
What is the splanchnocranium derived from?
Embryonic visceral arches
What do visceral arches 1 & 2 develop into?
Jaws
Supports
What do visceral arches 3-7 develop into?
Gill Arches
What are the five regions of the Branchiocranium?
Mandibular Arch
Palatine
Hyoid
Opercular
Branchial
What makes the branchiocranium?
Endochondral Bone
Dermal Bone
What bones make the Mandibular Arch of the branchiocranium in Bony Fish?
Maxillae
Premaxillae
Supramaxillae
Dentary
Angular
Articular
What bones make the Mandibular Arch of the branchinocranium in Cartilagenous Fish?
Palatoquadrate
Maxillae
Premaxillae
Supramaxillae
Meckel's Cartilage
Dentary
Articular
Angular
What is different about the mandibular arch of cartilaginous fish and bony fish?
Cartilagenous Fish have a palatoquadrate and meckel's cartilage
What group of fish have holostylic suspension of their jaw?
Holocephalins
What group of fishes have Amphistylic Suspension of their jaw?
Elasmobranchs
Actinopterygians
What group of fish have Autostyli suspension of their jaw?
Dipnoi
What bones comprise the palatine arch?
Palatine
Ectopterygoid
Mesopterygoid
Metapterygoid
Quadrate
Symplectic
Hyomandibula
What is notable about the bones of the palatine arch of the branchinocranium?
They are paired
What is notable about the bones of the hyoid arch?
They are paired
What bones make the hyoid arch of the branchiocranium?
Hypohal
Ceratohyal
Ephihyal
Interhyal
Glossohyal
Branchiostegal Rays
Urohyal