Stroma (fluid)

Stroma, in botany, refers to the colorless fluid surrounding the grana within the chloroplast.

Within the stroma are grana, stacks of thylakoids, the sub-organelles, the daughter cells, where photosynthesis is commenced before the chemical changes are completed in the stroma.

Photosynthesis occurs in two stages. In the first stage, light-dependent reactions capture the energy of light and use it to make the energy-storage molecules ATP and NADPH. During the second stage, the light-independent reactions use these products to capture and reduce carbon dioxide.

The series of biochemical redox reactions which take place in the stroma are collectively called the Calvin cycle or light-independent reactions. There are three phases: carbon fixation, reduction reactions, and ribulose 1,5-bisphosphate (RuBP) regeneration.

The stroma is also the location of chloroplast DNA and chloroplast ribosomes, and thus also the location of molecular processes including chloroplast DNA replication, and transcription/translation of some chloroplast proteins.

Stroma

Stroma may refer to:

Biology

Stroma, Scotland

Stroma is an island off the northern coast of the mainland of Scotland. It is the most southerly of the islands in the Pentland Firth between the Orkney islands and Caithness, the northeasternmost part of the mainland. The name is from the Old Norse Straumr-øy meaning "island in the [tidal] stream".

The island's population fell from 375 people in 1901 to just 12 by 1961. The last native islanders left at the end of the following year, while Stroma's final abandonment came in 1997 when the lighthouse keepers and their families departed. Ancient stone structures testify to the presence of Stroma's earliest residents, while a Norse presence around 900–1,000 years ago is recorded in the Orkneyinga Saga. It has been politically united with Caithness since at least the 15th century. Although Stroma lies only a few miles off the Scottish coast, the savage weather and ferociously strong tides of the Pentland Firth meant that the island's inhabitants were very isolated, causing them to be largely self-sufficient, trading agricultural produce and fish with the mainlanders.

Stroma (animal tissue)

In animal tissue, stroma (from Greek στρῶμα, meaning “layer, bed, bed covering”) is the part of a tissue or organ that has a connective and structural role. It consists of all the parts which do not conduct the specific functions of the organ, for example, connective tissue, blood vessels, nerves, ducts, etc. The other part is the parenchyma, which is the cells that perform the function of the tissue or organ. There are multiple ways of classifying tissues: one way of classifying tissues is based on their functions and another is based on their cellular components. Stromal tissue falls into the class that functions in contributing to the body’s support and movement. The cells that stroma tissues are composed of serve as a matrix in which the other cells are embedded. Stroma is made of various types of stromal cells.

Examples of stroma include:

Fluid

In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids. Fluids can be defined as substances that have zero shear modulus or in simpler terms a fluid is a substance which cannot resist any shear force applied to it.

Although the term "fluid" includes both the liquid and gas phases, in common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. For example, "brake fluid" is hydraulic oil and will not perform its required incompressible function if there is gas in it. This colloquial usage of the term is also common in medicine and in nutrition ("take plenty of fluids").

Liquids form a free surface (that is, a surface not created by the container) while gases do not. The distinction between solids and fluid is not entirely obvious. The distinction is made by evaluating the viscosity of the substance. Silly Putty can be considered to behave like a solid or a fluid, depending on the time period over which it is observed. It is best described as a viscoelastic fluid. There are many examples of substances proving difficult to classify. A particularly interesting one is pitch, as demonstrated in the pitch drop experiment currently running at the University of Queensland.

Fluid (disambiguation)

A fluid is defined as a substance that continually deforms (flows) under an applied shear stress.

Fluid may also refer to:

See also

Rushes (album)

Rushes is a 1998 ambient techno album by The Fireman, a duo consisting of Paul McCartney and producer Youth.

Recording

One line of lyrics included in the song "Palo Verde" was taken from an unreleased track of McCartney's, titled "Let Me Love You Always". Similarly, bits from another unreleased song, "Hey Now (What Are You Looking at Me For?)", was used in "Bison", "Auraveda" and "7 a.m.". Both unreleased tracks were recorded at some point during 1995, at McCartney's The Mill studio. In an edition of Club Sandwich magazine, two more songs were mentioned: "Plum Jam" and "Through the Marshes". All of the tracks featured on the album were recorded early 1998.

Release and reception

Better received than predecessor Strawberries Oceans Ships Forest, Rushes is distinguished by not relying so much on McCartney's previous recordings.

Rushes was released in the UK on Hydra on 21 September 1998, while in the US it was released on Capitol on 20 October 1998. The album was also released on double vinyl. Two 12" singles were released from the album, both mixes of "Fluid". The first 12", released on the same day as and with the same name as the album, contains the tracks "Fluid", "Appletree Cinnabar Amber", and an extended version of an album track titled "Bison (Long One)". The second 12" was released in 1999, as a limited edition of 3000, titled Fluid (Nitin Sawhney Remixes), and features three remixes of "Fluid" ("Fluid (Out of Body and Mind Mix)", "Fluid (Out of Body Mix)" and "Fluid (Out of Body with Sitar Mix)") and the album version of "Bison". Like the duo's first album,Rushes was a no-show on the charts and is also no longer in print.