A fenestra (fenestration; plural fenestrae or fenestrations) is any small opening or pore, commonly used as a term in the

biological sciences Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary ...

. It is the Latin word for "window", and is used in various fields to describe a pore in an

anatomical Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...

structure.

Biological morphology

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

, fenestrae are found in

cancellous bone A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, an ...

s, particularly in the skull. In

anatomy Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...

, the

round window The round window is one of the two openings from the middle ear into the inner ear. It is sealed by the secondary tympanic membrane (round window membrane), which vibrates with opposite phase to vibrations entering the inner ear through the oval w ...

and

oval window The oval window (or ''fenestra vestibuli'' or ''fenestra ovalis'') is a membrane-covered opening from the middle ear to the cochlea of the inner ear. Vibrations that contact the tympanic membrane travel through the three ossicles and into the in ...

are also known as the ''fenestra rotunda'' and the ''fenestra ovalis''. In

microanatomy Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...

, fenestrae are found in endothelium of fenestrated capillaries, enabling the rapid exchange of molecules between the blood and surrounding tissue. The elastic layer of the

tunica intima The tunica intima (New Latin "inner coat"), or intima for short, is the innermost tunica (layer) of an artery or vein. It is made up of one layer of endothelial cells and is supported by an internal elastic lamina. The endothelial cells are in ...

is a fenestrated membrane. In surgery, a fenestration is a new opening made in a part of the body to enable drainage or access.

Plant biology and mycology

In plant biology, the perforations in a

perforate leaf Perforate leaves, sometimes called fenestrate, occur naturally in some species of plants. Holes develop as a leaf grows. The size, shape, and quantity of holes in each leaf can vary greatly depending on the species and can even vary greatly withi ...

are also described as fenestrae, and the leaf is called a fenestrate leaf. The

leaf window Leaf window, also known as epidermal window, and fenestration. is a specialized leaf structure consisting of a translucent area through which light can enter the interior surfaces of the leaf where photosynthesis can occur. The translucent structu ...

is also known as a fenestra, and is a translucent structure that transmits light, as in ''

Fenestraria ''Fenestraria'' (known as babies' toes or window plant) is a (possibly monotypic) genus of succulent plants in the family Aizoaceae, native to the Namaqualand in Namibia. Description The only species currently recognised in this genus is ' ...

''. Examples of fenestrate structures in the fungal kingdom include the symmetrically arranged gaps in the indusium ("skirt") of the mushroom '' Phallus duplicatus'', and the thallus of the coral lichen ''

Pulchrocladia retipora ''Pulchrocladia retipora'', most commonly known as the coral lichen, is a species of fruticose lichen in the family Cladoniaceae. It occurs in Australasia and New Caledonia where it grows in coastal and alpine heathlands. The lichen features cor ...

''.

Zoology

In zoology, the trilobite ''

Fenestraspis ''Fenestraspis'' is an extinct genus of trilobite in the order Phacopida from the Upper Pragian and Lower Emsian. ''Fenestraspis'' is unusual because of the development of extensive fenestrae in the posterior part of the body and apparently o ...

'' possessed extensive fenestrae in the posterior part of the body. In the

paleognathae Palaeognathae (; ) is a infraclass of birds, called paleognaths, within the class Aves of the clade Archosauria. It is one of the two extant infraclasses of birds, the other being Neognathae, both of which form Neornithes. Palaeognathae contai ...

, there is an ilio–ischiatic fenestra. Fenestrae are also used to distinguish the three types of

amniote Amniotes are a clade of tetrapod vertebrates that comprises sauropsids (including all reptiles and birds, and extinct parareptiles and non-avian dinosaurs) and synapsids (including pelycosaurs and therapsids such as mammals). They are distin ...

References

{{Reflist, colwidth=30em, refs= {{cite book , last1=Kiernan , first1=J.A. , last2=Barr , first2=Murray Llewellyn , title=Barr's the Human Nervous System: An Anatomical Viewpoint , publisher=Wolters Kluwer Health/Lippincott Williams & Wilkins , publication-place=Philadelphia , year=2009 , isbn=978-0-7817-8256-2 , oclc=219262888 , page=320 {{cite book , last1=Beentje , first1=H. , last2=Williamson , first2=J. , year=2010 , title=The Kew Plant Glossary: An Illustrated Dictionary of Plant Terms , publisher=Kew Publishing , location=Royal Botanic Gardens, Kew , page=47 {{cite dictionary , last=Dorland , first=W. A. Newman , title=Dorland's Illustrated Medical Dictionary , edition=28th , publisher=Saunders , publication-place=Philadelphia , year=1994 , isbn=978-0-7216-2859-2 , oclc=30948606 , page=615 {{cite journal , first1=David J. , last1=Holloway , first2=Maria da Gloria Pires de , last2=Carvalho , year=2009 , title=The extraordinary trilobite ''Fenestraspis'' (Dalmanitidae, Synphoriinae) from the Lower Devonian of Bolivia , journal= Palaeontology , volume=52 , issue=4 , pages=933–949 , doi=10.1111/j.1475-4983.2009.00878.x , doi-access=free {{cite book , last1=Krstić , first=Radivoj V. , title=Human Microscopic Anatomy: An Atlas for Students of Medicine and Biology , publisher=Springer Berlin Heidelberg , publication-place=Berlin, Heidelberg , year=1991 , isbn=978-3-662-02676-2 , oclc=851388484 , page=56 {{cite journal , last1=Stocker-Wörgötter , first1=Elfie , last2=Elix , first2=John A. , year=2006 , title=Morphogenetic strategies and induction of secondary metabolite biosynthesis in cultured lichen-forming Ascomycota, as exemplified by ''Cladia retipora'' (Labill.) Nyl. and ''Dactylina arctica'' (Richards) Nyl. , journal=Symbiosis , volume=40 , pages=9–20 , url=https://dalspace.library.dal.ca/bitstream/handle/10222/78197/VOLUME%2041-NUMBER%201-2006-PAGE%209.pdf?sequence=1 {{cite book , last1=Ulloa , first1=Miguel , last2=Halin , first2=Richard T. , title=Illustrated Dictionary of Mycology , edition=2nd , year=2012 , publisher=The American Phytopathological Society , location=St. Paul, Minnesota , isbn=978-0-89054-400-6 , page=220 Anatomy Biology Angiology Fungal morphology and anatomy sv:Fenestrae

Biological morphology

Plant biology and mycology

Zoology

See also

References