operculum
Fish gill flap
An operculum is a lid-like covering or flap.
In fish, the operculum is the bony plate protecting the gills: Water exits through the operculum as the fish breathes.
In snails, it's the hard disc that seals the shell opening when the animal withdraws.
The term appears in botany for the cap on certain seed pods and moss capsules.
Plural: opercula or operculums.
Spore-bearing ground cover
Shelled, slow-moving mollusk
- gastropodSingle-shelled soft creature
- shellHard outer covering
- whorlSpiral arrangement of ridges
- apertureAdjustable optical inlet
trapdoor · hermit crab · sea snail · periwinkle · conch · whelk · retraction · foot
Hard outer covering
- valveFluid flow controller
- pedicleNarrow tissue stalk
- articulateExpress clearly, or well-spoken
- inarticulateUnable to express clearly
fossil · Paleozoic · marine · invertebrate
Gilled aquatic vertebrate
- teleostBony, ray-finned fish
- bony fishFish with calcified skeleton
- aquariumTank for keeping fish
- respirationGas exchange in organisms
cartilaginous · swim bladder · fins · scales · ichthyology · vertebrate · freshwater · saltwater
Dependent territorial settlement
- encrustingForming a hardened covering
- marineRelating to the sea
- freshwaterNon-saline aquatic environment
- aviculariumModified bryozoan zooid
ectoproct · colonial · calcified · skeletal · invertebrate
Of the fore side
- parietalOf the skull wall
- temporalRelating to chronology
- insulaBuried cortical lobe
- cortexOrgan's external tissue
cerebral · neuroanatomy · gyrus · sulcus · lobe · fMRI · somatosensory · motor cortex
moss
Spore-bearing ground cover
lid · hornwort · liverwort · pitcher plant · carnivorous plant
snail
Shelled, slow-moving mollusk
aperture · trapdoor · hermit crab · sea snail · periwinkle · conch · whelk · retraction · foot · mantle
shell
Hard outer covering
- valveFluid flow controller
- pedicleNarrow tissue stalk
- articulateExpress clearly, or well-spoken
inarticulate · fossil · Paleozoic · marine · invertebrate
fish
Gilled aquatic vertebrate
respiration · cartilaginous · swim bladder · fins · scales · ichthyology · vertebrate · freshwater · saltwater
colony
Dependent territorial settlement
- encrustingForming a hardened covering
- marineRelating to the sea
- freshwaterNon-saline aquatic environment
avicularium · ectoproct · colonial · calcified · skeletal · invertebrate
frontal
Of the fore side
cortex · cerebral · neuroanatomy · gyrus · sulcus · lobe · fMRI · somatosensory · motor cortex · forebrain