Changes

==Origin==

==Origin==

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] ''diafragma'', from Late Latin ''diaphragma'', from [[Greek]], from ''diaphrassein'' to barricade, from ''dia''- + ''phrassein'' to enclose

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] ''diafragma'', from Late Latin ''diaphragma'', from [[Greek]], from ''diaphrassein'' to barricade, from ''dia''- + ''phrassein'' to enclose

*[http://en.wikipedia.org/wiki/14th_century 14th Century]

*[https://en.wikipedia.org/wiki/14th_century 14th Century]

==Definitions==

==Definitions==

*1: a [[body]] partition of muscle and connective tissue; specifically : the partition [[separating]] the chest and abdominal cavities in [[mammals]]

*1: a [[body]] partition of muscle and connective tissue; specifically : the partition [[separating]] the chest and abdominal cavities in [[mammals]]

==Description==

==Description==

:''Anatomy''

:''Anatomy''

In the [[anatomy]] of [[mammals]], the ''thoracic diaphragm'', or simply the '''diaphragm''' (Ancient Greek: διάφραγμα diáphragma "partition"), is a sheet of internal skeletal muscle that extends across the bottom of the rib cage. The diaphragm separates the [http://en.wikipedia.org/wiki/Thoracic_cavity thoracic cavity] ([[heart]], lungs & ribs) from the [http://en.wikipedia.org/wiki/Abdominal_cavity abdominal cavity] and performs an important function in [[respiration]]: as the diaphragm contracts, the volume of the thoracic cavity increases and air is drawn into the lungs.

In the [[anatomy]] of [[mammals]], the ''thoracic diaphragm'', or simply the '''diaphragm''' (Ancient Greek: διάφραγμα diáphragma "partition"), is a sheet of internal skeletal muscle that extends across the bottom of the rib cage. The diaphragm separates the [https://en.wikipedia.org/wiki/Thoracic_cavity thoracic cavity] ([[heart]], lungs & ribs) from the [https://en.wikipedia.org/wiki/Abdominal_cavity abdominal cavity] and performs an important function in [[respiration]]: as the diaphragm contracts, the volume of the thoracic cavity increases and air is drawn into the lungs.

A "diaphragm" in anatomy can refer to other flat structures such as the [http://en.wikipedia.org/wiki/Urogenital_diaphragm urogenital diaphragm] or [http://en.wikipedia.org/wiki/Pelvic_diaphragm pelvic diaphragm], but "the diaphragm" generally refers to the thoracic diaphragm. Other vertebrates such as amphibians and reptiles have diaphragm-like structures, but important details of the anatomy vary, such as the position of lungs in the abdominal cavity.

A "diaphragm" in anatomy can refer to other flat structures such as the [https://en.wikipedia.org/wiki/Urogenital_diaphragm urogenital diaphragm] or [https://en.wikipedia.org/wiki/Pelvic_diaphragm pelvic diaphragm], but "the diaphragm" generally refers to the thoracic diaphragm. Other vertebrates such as amphibians and reptiles have diaphragm-like structures, but important details of the anatomy vary, such as the position of lungs in the abdominal cavity.

:''Optics''

:''Optics''

In [[optics]], a ''diaphragm'' is a thin opaque structure with an opening ([[aperture]]) at its center. The role of the diaphragm is to stop the passage of [[light]], except for the light passing through the aperture. Thus it is also called a stop (an [http://en.wikipedia.org/wiki/Aperture_stop aperture stop], if it limits the brightness of light reaching the focal plane, or a field stop or flare stop for other uses of diaphragms in lenses). The diaphragm is placed in the light path of a lens or [http://en.wikipedia.org/wiki/Photographic_lens objective], and the size of the aperture regulates the amount of light that passes through the lens. The centre of the diaphragm's aperture coincides with the [http://en.wikipedia.org/wiki/Optical_axis optical axis] of the lens system.

In [[optics]], a ''diaphragm'' is a thin opaque structure with an opening ([[aperture]]) at its center. The role of the diaphragm is to stop the passage of [[light]], except for the light passing through the aperture. Thus it is also called a stop (an [https://en.wikipedia.org/wiki/Aperture_stop aperture stop], if it limits the brightness of light reaching the focal plane, or a field stop or flare stop for other uses of diaphragms in lenses). The diaphragm is placed in the light path of a lens or [https://en.wikipedia.org/wiki/Photographic_lens objective], and the size of the aperture regulates the amount of light that passes through the lens. The centre of the diaphragm's aperture coincides with the [https://en.wikipedia.org/wiki/Optical_axis optical axis] of the lens system.

Most modern cameras use a type of adjustable diaphragm known as an iris diaphragm, and often referred to simply as an iris.

Most modern cameras use a type of adjustable diaphragm known as an iris diaphragm, and often referred to simply as an iris.

See the articles on aperture and [http://en.wikipedia.org/wiki/F-number f-number] for the photographic effect and system of quantification of varying the opening in the diaphragm.

See the articles on aperture and [https://en.wikipedia.org/wiki/F-number f-number] for the photographic effect and system of quantification of varying the opening in the diaphragm.

[[Category: Biology]]

[[Category: Biology]]

[[Category: Physics]]

[[Category: Physics]]