gill slit
Aquatic breathing opening
Gill slits are openings on each side of a fish or aquatic animal through which water passes after flowing over the gills, allowing the animal to extract oxygen.
In embryology, gill slits appear briefly in vertebrate embryos—including humans—before developing into other structures, evidence of shared evolutionary ancestry.
Element eight, colorless gas
- gas exchangeTransfer of respiratory molecules
- water flowMovement of liquid mass
- ventilationCirculation of fresh air
- diffusionPassive molecular spreading
breathing · dissolved oxygen · carbon dioxide · blood flow · osmoregulation · excretion · ammonia
Cartilaginous marine predator
- rayNarrow light emission
- skateGliding boot or flatfish
- lampreyJawless parasitic fish
- hagfishJawless, slime-producing marine fish
lancelet · jawless fish · tadpole · salamander · axolotl · whale shark · basking shark · manta ray
Structural similarity through descent
- embryologyStudy of prenatal development
- vertebrateSpinal column animal
- ancestryFamily line of descent
- fossilsPreserved ancient organism traces
Cambrian · adaptation · chordate · development · ontogeny · recapitulation · vestigial · common ancestor
Of aquatic breathing organs
- pharyngealOf the throat cavity
- operculumAnatomical lid structure
- spiracleExternal respiratory aperture
- lamellaeThin parallel plates
cartilaginous · ventral · dorsal · countercurrent · epithelium · capillaries · mucous
oxygen
Element eight, colorless gas
- gas exchangeTransfer of respiratory molecules
- water flowMovement of liquid mass
- ventilationCirculation of fresh air
diffusion · breathing · dissolved oxygen · carbon dioxide · blood flow · osmoregulation · excretion · ammonia
shark
Cartilaginous marine predator
hagfish · lancelet · jawless fish · tadpole · salamander · axolotl · whale shark · basking shark · manta ray · dogfish
homology
Structural similarity through descent
- embryologyStudy of prenatal development
- vertebrateSpinal column animal
- ancestryFamily line of descent
fossils · Cambrian · adaptation · chordate · development · ontogeny · recapitulation · vestigial · common ancestor · Darwin
branchial
Of aquatic breathing organs
- pharyngealOf the throat cavity
- operculumAnatomical lid structure
- spiracleExternal respiratory aperture
lamellae · cartilaginous · ventral · dorsal · countercurrent · epithelium · capillaries · mucous