Definition of operculum in English:

operculum

nounPlural opercula ə(ʊ)ˈpəːkjʊləmoʊˈpərkjələm

Zoology Botany

1A structure that closes or covers an aperture.
Example sentencesExamples
- The archeopyle is created by loss of an operculum that is distinguished from the adjacent cyst surface by a distinct groove.
- It is able to withdraw the whole of its body into its shell which is then sealed by an amber-coloured operculum.
- Whenever muscular control of the operculum was established (presumably very early), it was probably based on the cleithrum.
- In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum.
- Therefore, the operculum is always visible in complete specimens.
1. 1.1
  technical term for gill cover
  Example sentencesExamples
  The nape lacks cirri, and the first gill arch attaches to the operculum, the latter characteristic distinguishing Tripterygiidae from Clinidae.
  Due to the close proximity of the operculum and the pectoral fins, water jetting out of the operculum could affect flow over the pectoral fins, possibly changing locomotory efficiency.
  On the bottom of their operculum or gill-cover, they have a sharp spine. Angelfish all vary in color and pattern.
  In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum.
  These fish do not have gills or opercula (gill coverings) like most bony fishes.
2. 1.2 A secreted plate that closes the aperture of a gastropod mollusc's shell when the animal is retracted.
  Example sentencesExamples
  Above the head and the arms is a leathery, protective hood, that acts like an operculum to protect the animal when it withdraws inside its shell.
  Many snails have an operculum, a horny plate that seals the opening when the snail's body is drawn into the shell.
  From the shape of Macluritid opercula, we know that Macluritids are dextral shells with a depressed (sunken or downward pointing) spire, not left-handed shells with a normal elevated one.
  Immobilizing snails caused them to draw their operculum deep within their shell, which may have restricted the crabs' ability to extract the flesh from the shell, even with extensive apertural breakage.
  They inhabit salt marshes near the sea, and are able to seal the shell with the operculum and so survive dry periods buried in mud.
3. 1.3 A part of the spore-containing capsule of a moss that functions as a lid or cover.
  Example sentencesExamples
  As the spores grow, fluid pressure builds up in the ascus until the operculum bursts open and the ascospores are blown out into the environment.
  The sporophytes also develop opercula, peristomes, continuous columella, and a spongy layer between the amphithecium and the spore mass.

Derivatives

opercular

adjective ə(ʊ)ˈpəːkjʊləoʊˈpərkjələr

Botany Zoology

Relating to or denoting a structure that closes or covers an aperture such as a fish's gills.
age and growth of individual fish were determined from opercular bones
Example sentencesExamples
- A key component of this relationship in rainbow trout was the timing of body velocity (aka ram movement) during opercular abduction which prevented backflow of water into the opercular cavity.
- We then determined phase differences between pectoral fin beating and opercular jetting (respiration).
- Moreover, since the opercular openings are quite small and the musculature responsible for abduction is not fully developed, fluid will tend to flow out of the mouth as the hyoid returns to its resting position.

operculate

adjective ə(ʊ)ˈpəːkjʊlətoʊˈpərkjəˌleɪt

Botany Zoology

The Amphibolids are the only operculate pulmonates.
Consequently, Peziza and other forms have evolved asci which are operculate, meaning that they have a sort of lid on the end.

Origin

Early 18th century: from Latin, literally 'lid, covering', from operire 'to cover'.

Definition of operculum in US English:

operculum

nounōˈpərkyələmoʊˈpərkjələm

Botany Zoology

1A structure that closes or covers an aperture.
Example sentencesExamples
- The archeopyle is created by loss of an operculum that is distinguished from the adjacent cyst surface by a distinct groove.
- In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum.
- Therefore, the operculum is always visible in complete specimens.
- It is able to withdraw the whole of its body into its shell which is then sealed by an amber-coloured operculum.
- Whenever muscular control of the operculum was established (presumably very early), it was probably based on the cleithrum.
1. 1.1
  technical term for gill cover
  Example sentencesExamples
  These fish do not have gills or opercula (gill coverings) like most bony fishes.
  The nape lacks cirri, and the first gill arch attaches to the operculum, the latter characteristic distinguishing Tripterygiidae from Clinidae.
  In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum.
  Due to the close proximity of the operculum and the pectoral fins, water jetting out of the operculum could affect flow over the pectoral fins, possibly changing locomotory efficiency.
  On the bottom of their operculum or gill-cover, they have a sharp spine. Angelfish all vary in color and pattern.
2. 1.2 A secreted plate that closes the aperture of a gastropod mollusk's shell when the animal is retracted.
  Example sentencesExamples
  They inhabit salt marshes near the sea, and are able to seal the shell with the operculum and so survive dry periods buried in mud.
  Above the head and the arms is a leathery, protective hood, that acts like an operculum to protect the animal when it withdraws inside its shell.
  From the shape of Macluritid opercula, we know that Macluritids are dextral shells with a depressed (sunken or downward pointing) spire, not left-handed shells with a normal elevated one.
  Immobilizing snails caused them to draw their operculum deep within their shell, which may have restricted the crabs' ability to extract the flesh from the shell, even with extensive apertural breakage.
  Many snails have an operculum, a horny plate that seals the opening when the snail's body is drawn into the shell.
3. 1.3 A part of the spore-containing capsule of a moss that functions as a lid or cover.
  Example sentencesExamples
  The sporophytes also develop opercula, peristomes, continuous columella, and a spongy layer between the amphithecium and the spore mass.
  As the spores grow, fluid pressure builds up in the ascus until the operculum bursts open and the ascospores are blown out into the environment.

Origin

Early 18th century: from Latin, literally ‘lid, covering’, from operire ‘to cover’.

单词	operculum
释义	Definition of operculum in English: operculum nounPlural opercula ə(ʊ)ˈpəːkjʊləmoʊˈpərkjələm Zoology Botany 1A structure that closes or covers an aperture. Example sentencesExamples The archeopyle is created by loss of an operculum that is distinguished from the adjacent cyst surface by a distinct groove. It is able to withdraw the whole of its body into its shell which is then sealed by an amber-coloured operculum. Whenever muscular control of the operculum was established (presumably very early), it was probably based on the cleithrum. In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum. Therefore, the operculum is always visible in complete specimens. 1.1 technical term for gill cover Example sentencesExamples The nape lacks cirri, and the first gill arch attaches to the operculum, the latter characteristic distinguishing Tripterygiidae from Clinidae. Due to the close proximity of the operculum and the pectoral fins, water jetting out of the operculum could affect flow over the pectoral fins, possibly changing locomotory efficiency. On the bottom of their operculum or gill-cover, they have a sharp spine. Angelfish all vary in color and pattern. In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum. These fish do not have gills or opercula (gill coverings) like most bony fishes. 1.2 A secreted plate that closes the aperture of a gastropod mollusc's shell when the animal is retracted. Example sentencesExamples Above the head and the arms is a leathery, protective hood, that acts like an operculum to protect the animal when it withdraws inside its shell. Many snails have an operculum, a horny plate that seals the opening when the snail's body is drawn into the shell. From the shape of Macluritid opercula, we know that Macluritids are dextral shells with a depressed (sunken or downward pointing) spire, not left-handed shells with a normal elevated one. Immobilizing snails caused them to draw their operculum deep within their shell, which may have restricted the crabs' ability to extract the flesh from the shell, even with extensive apertural breakage. They inhabit salt marshes near the sea, and are able to seal the shell with the operculum and so survive dry periods buried in mud. 1.3 A part of the spore-containing capsule of a moss that functions as a lid or cover. Example sentencesExamples As the spores grow, fluid pressure builds up in the ascus until the operculum bursts open and the ascospores are blown out into the environment. The sporophytes also develop opercula, peristomes, continuous columella, and a spongy layer between the amphithecium and the spore mass. Derivatives opercular adjective ə(ʊ)ˈpəːkjʊləoʊˈpərkjələr Botany Zoology Relating to or denoting a structure that closes or covers an aperture such as a fish's gills. age and growth of individual fish were determined from opercular bones Example sentencesExamples A key component of this relationship in rainbow trout was the timing of body velocity (aka ram movement) during opercular abduction which prevented backflow of water into the opercular cavity. We then determined phase differences between pectoral fin beating and opercular jetting (respiration). Moreover, since the opercular openings are quite small and the musculature responsible for abduction is not fully developed, fluid will tend to flow out of the mouth as the hyoid returns to its resting position. operculate adjective ə(ʊ)ˈpəːkjʊlətoʊˈpərkjəˌleɪt Botany Zoology The Amphibolids are the only operculate pulmonates. Consequently, Peziza and other forms have evolved asci which are operculate, meaning that they have a sort of lid on the end. Origin Early 18th century: from Latin, literally 'lid, covering', from operire 'to cover'. Definition of operculum in US English: operculum nounōˈpərkyələmoʊˈpərkjələm Botany Zoology 1A structure that closes or covers an aperture. Example sentencesExamples The archeopyle is created by loss of an operculum that is distinguished from the adjacent cyst surface by a distinct groove. In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum. Therefore, the operculum is always visible in complete specimens. It is able to withdraw the whole of its body into its shell which is then sealed by an amber-coloured operculum. Whenever muscular control of the operculum was established (presumably very early), it was probably based on the cleithrum. 1.1 technical term for gill cover Example sentencesExamples These fish do not have gills or opercula (gill coverings) like most bony fishes. The nape lacks cirri, and the first gill arch attaches to the operculum, the latter characteristic distinguishing Tripterygiidae from Clinidae. In amphibians the inner ear is mechanically coupled to the pectoral girdle through the operculum. Due to the close proximity of the operculum and the pectoral fins, water jetting out of the operculum could affect flow over the pectoral fins, possibly changing locomotory efficiency. On the bottom of their operculum or gill-cover, they have a sharp spine. Angelfish all vary in color and pattern. 1.2 A secreted plate that closes the aperture of a gastropod mollusk's shell when the animal is retracted. Example sentencesExamples They inhabit salt marshes near the sea, and are able to seal the shell with the operculum and so survive dry periods buried in mud. Above the head and the arms is a leathery, protective hood, that acts like an operculum to protect the animal when it withdraws inside its shell. From the shape of Macluritid opercula, we know that Macluritids are dextral shells with a depressed (sunken or downward pointing) spire, not left-handed shells with a normal elevated one. Immobilizing snails caused them to draw their operculum deep within their shell, which may have restricted the crabs' ability to extract the flesh from the shell, even with extensive apertural breakage. Many snails have an operculum, a horny plate that seals the opening when the snail's body is drawn into the shell. 1.3 A part of the spore-containing capsule of a moss that functions as a lid or cover. Example sentencesExamples The sporophytes also develop opercula, peristomes, continuous columella, and a spongy layer between the amphithecium and the spore mass. As the spores grow, fluid pressure builds up in the ascus until the operculum bursts open and the ascospores are blown out into the environment. Origin Early 18th century: from Latin, literally ‘lid, covering’, from operire ‘to cover’.
随便看	photodimerization photodimerize photodiode photodiodes photodisintegrate photodisintegration photodissociable photodissociate photodissociate photodissociation photodrama photodrome photoduplicate photoduplicate photoduplicating photoduplication photodynamic photodynamical photodynamically photodynamically photodynamics photodynamic therapy photoed photoeffect photoejection