Arch is a structure, consisting of a curved op on two supports, that holds the weight of something above it. The word arch is used in various fields and has different meanings. Like in the medical field, the arch is any organ or part of the body that is curved in shape etc.
Arch
Arch (architecture)
Arch is a curving element used to bridge an opening and support loads from above in architecture and civil engineering. The arch served as the foundation for the vault’s development.
The wedge plays a crucial role in arch construction. The outcome is an arch if a series of wedge-shaped blocks—those with the upper edge wider than the lower edge—are placed flank to flank in the way illustrated in the image. The blocks are known as vossoirs. Each voussoir must be carefully carved to ensure that it presses firmly on the surface of adjacent blocks and distributes stresses evenly. The keystone refers to the centre voussoir. The spring, or springing line, is the point at which the arch rises from its vertical supports. The voussoirs require support from below during the construction of an arch until the keystone is fixed in place; this support is normally in the form of temporary wooden centring. Semicircular, segmental (less than one-half of a circle), or pointed (two intersecting arcs of a circle) curves can all be utilized successfully in an arch; noncircular curves can also be used successfully.
Pharyngeal Arch:
The pharyngeal arches, also known as visceral arches, are recognisable antecedents for several structures in the embryonic development of vertebrates. The arches are known as branchial arches or gill arches in fish.
The arches first appear in the human embryo around the fourth week of development. On both sides of the growing pharynx, they appear as a succession of mesoderm outpouchings. The aortic arches are the pharyngeal arches’ vascular system.
The gills are supported by the branchial arches in fish.
Branchial Arch:
Branchial arches, also known as gill arches, are a series of bony “loops” that support the gills of fish. All vertebrate embryos generate pharyngeal arches since gills are the fundamental state of vertebrates, albeit the fate of these arches differs by taxon. The first arch forms the jaws, the second the hyomandibular complex, and the posterior arches support the gills in jawed fish. Many features, notably the gill arches, are eliminated in amphibians and reptiles, leaving only the mouth jaws and a hyoid system. The hyoid in mammals and birds is even more simple.
Gills are used by all basic vertebrates to breathe. The gills run behind the head, abutting the rear borders of a series of apertures from the oesophagus to the outside. There are four pairs of arches in bony fish, five to seven pairs in cartilaginous fish, and seven pairs in primitive jawless fish. Because certain chordate relatives have more than 50 pairs of gills, the vertebrate ancestor must have had more arches.
External gills branch off from the gill arches in amphibians and some primitive bony fish larvae. In adulthood, the function of these organs is taken over by the gills themselves in fish and the lungs in most amphibians. The intricate internal gill system observed in fish appears to have been irreversibly lost relatively early in the evolution of tetrapods, with certain amphibians retaining the external larval gills in adulthood.
Arc Length Formula
The distance between two places along a portion of a curve is known as arc length.
Curve rectification is the process of determining the length of an uneven arc segment. A curve is considered to be rectifiable if its rectification yields a finite number (and hence the curve has a finite length). Infinitesimal calculus gave rise to a generic formula that, in some situations, yields closed-form answers.
Arc length formula radians
If the is given in radians,
S=θ×r
Arc length formula degrees
If the is given in degrees,
S=2πr(θ/360)
Arc length formula integral form
Integral form, 
Where, S is arc length of the circle,
R is radius of the circle,
is central angle of a circle.
Arch Enemy Meaning
Arch Enemy is a Swedish melodic death metal band that started in 1995 as a supergroup from Halmstad. Carcass, Armageddon, Carnage, Mercyful Fate, Spiritual Beggars, The Agonist, Nevermore, and Eucharist were among its members. It was created by Michael Amott, the guitarist for Carcass, and Johan Liiva, who were also members of the death metal band Carnage. Ten studio albums, three live albums, three video albums, and four EPs have been released by the band. Johan Liiva was the band’s initial frontwoman, but she was replaced in 2000 by German vocalist Angela Gossow. Gossow left the band in March 2014 to become the band’s manager, and was replaced by Alissa White-Gluz, a Canadian vocalist.
Conclusion
An arc is a smooth curve that connects two points in mathematics. An arc is one of the parts of a circle in general. It is essentially a portion of a circle’s circumference. The branchial arches are embryologic structures that mature into anatomical features in adults. The term “branchial” is derived from the Latin word “branchia,” which means “gills,” and is used to describe the development of a variety of fish and amphibian species.