The skeletons of a man and a horse placed in a display in the Australian Museum, Sydney.

The skeleton (From Greek σκελετός, skeletos = "dried-body", "mummy") is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.

In a figurative sense, skeleton can refer to technology that supports a structure such as a building.

Types of skeletons[link]

Exoskeleton[link]

Exoskeleton of an ant

Exoskeletons are external, and are found in many invertebrates; they enclose and protect the soft tissues and organs of the body. Some kinds of exoskeletons undergo periodic moulting as the animal grows, as is the case in many arthropods including insects and crustaceans. Exoskeletons are made of different materials including chitin (in arthropods), calcium compounds (in corals and mollusks) and silicate (for diatoms and radiolarians).

The exoskeleton of insects is not only a protection but also serves as a surface for muscle attachment, as a watertight protection against drying and as a sense organ to interact with their environments. The shell of mollusks also performs all of the same functions, except that in most cases it does not contain sense organs.

An external skeleton can be quite heavy in relation to the overall mass of an animal, so on land, organisms that have an exoskeleton are mostly relatively small. Somewhat larger aquatic animals can support an exoskeleton because weight is less of a consideration underwater. The southern giant clam, a species of extremely large saltwater clam in the Pacific Ocean, has a shell that is massive in both size and weight. Syrinx aruanus is a species of sea snail with a very large shell.

Endoskeleton[link]

Endoskeleton of an elephant.

A beaver skeleton on display at The Museum of Osteology, Oklahoma City, Oklahoma.

Endoskeletons is the internal support structure of an animal, composed of mineralized tissue and are typical of many vertebrates. They vary in complexity such as functioning purely for support (as in the case of sponges), but often serves as an attachment site for muscle and a mechanism for transmitting muscular forces. A true endoskeleton is derived from mesodermal tissue. Such a skeleton is present in echinoderms and chordates.

Sponges[link]

The skeleton of sponges consists of microscopic calcareous or silicious spicules. The demosponges include 90% of all species of sponges. Their "skeletons" are made of spicules consisting of fibers of the protein spongin, the mineral silica, or both. Where spicules of silica are present, they have a different shape from those in the otherwise similar glass sponges.^[1]

Echinoderms[link]

The skeleton of the echinoderms, which include, among other things, the starfish, is composed of calcite and a small amount of magnesium oxide. It lies below the epidermis in the mesoderm and is within cell clusters of frame-forming cells. This structure formed is porous and therefore firm and at the same time light. It coalesces into small calcareous ossicles (bony plates), which can grow in all directions and thus can replace the loss of a body part. Connected by joints, the individual skeletal parts can be moved by the muscles.

Chordates[link]

In humans and generally in most vertebrates, the main skeletal component is referred to as bone. Another important component is cartilage. In mammals they are found mainly in the joint areas. In other animals, such as the cartilaginous fishes, which include the sharks, the skeleton is composed entirely of cartilage.

Bones in addition to supporting the body also serve, at the cellular level, as calcium and phosphate storage.

Fish[link]

The skeleton of the fish is either made of cartilage (cartilage fish) or bones (bony fishes). The main features of the fish, the fins, are bony fin rays and, except the caudal fin, have no direct connection with the spine. They are supported only by the muscles. The ribs attach to the spine.

Birds[link]

The bird skeleton is highly adapted for flight. It is extremely lightweight but strong enough to withstand the stresses of taking off, flying, and landing. One key adaptation is the fusing of bones into single ossifications, such as the pygostyle. Because of this, birds usually have a smaller number of bones than other terrestrial vertebrates. Birds also lack teeth or even a true jaw, instead having evolved a beak, which is far more lightweight. The beaks of many baby birds have a projection called an egg tooth, which facilitates their exit from the amniotic egg.

Marine mammals[link]

To facilitate movement of marine mammals in the water, the hind legs were either lost altogether, as in the whales and manatees, or united in a single tail fin e.g., pinniped seals.

Hydrostatic skeleton[link]

The most simple form of skeleton is the hydrostatic skeleton found in many cold-blooded organisms and soft-bodied animals. The pressure of the fluid and action of the surrounding muscles are used to change an organism's shape and produce movement. This fluid filled cavity is known as the coelom. Invertebrates such as starfish, sea urchins, jellyfish and earthworms have this form of a skeleton. The hydrostatic skeleton has some similarities to muscular hydrostats.

Cytoskeleton[link]

The cytoskeleton (gr. kytos = cell) is used to stabilize and preserve the form of the cells. It is a dynamic structure that maintains cell shape, protects the cell, enables cellular motion (using structures such as flagella, cilia and lamellipodia), and plays important roles in both intracellular transport (the movement of vesicles and organelles, for example) and cellular division.

Human[link]

Study of Skeletons, c. 1510, by Leonardo da Vinci

The human skeleton consists of both fused and individual bones supported and supplemented by ligaments, tendons, muscles and cartilage. It serves as a scaffold which supports organs, anchors muscles, and protects organs such as the brain, lungs and heart. Although the teeth do not consist of tissue commonly found in other bones, the teeth are considered bones and are a member of the skeletal system. The biggest bone in the body is the femur in the upper leg, and the smallest is the stapes bone in the middle ear. In an adult, the skeleton comprises around 14% of the total body weight,^[2] and half of this weight is water.

Fused bones include those of the pelvis and the cranium. Not all bones are interconnected directly: There are three bones in each middle ear called the ossicles that articulate only with each other. The hyoid bone, which is located in the neck and serves as the point of attachment for the tongue, does not articulate with any other bones in the body, being supported by muscles and ligaments.

There are 206 bones in the adult human skeleton (this number depends on whether the pelvic bones (the os innominatum on each side) are counted as one or three bones on each side (ilium, ischium, and pubis), whether the coccyx or tail bone is counted as one or four separate bones, and does not count the variable wormian bones between skull sutures. Similarly, the sacrum is usually counted as a single bone, rather than five fused vertebrae. There is also a variable number of small sesamoid bones, commonly found in tendons. The patella or kneecap on each side is an example of a larger sesamoid bone. The patellae are counted in the total, as they are constant). The number of bones varies between individuals and with age - newborn babies have over 270 bones^[3][4][5] some of which fuse together. These bones are organized into a longitudinal axis, the axial skeleton, to which the appendicular skeleton is attached.^[6]

The human skeleton takes 20 years before it is fully developed. In many animals, the skeleton bones contain marrow, which produces blood cells. ^[7]

Much of the human skeleton maintains the ancient segmental pattern present in all vertebrates (mammals, birds, fish, reptiles and amphibians) with basic units being repeated. This segmental pattern is particularly evident in the vertebral column and in the ribcage.

Bones and cartilage[link]

Bone[link]

Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue. Because bones come in a variety of shapes and have a complex internal and external structure they are lightweight, yet strong and hard, in addition to fulfilling their many other functions. One of the types of tissue that makes up bone is the mineralized osseous tissue, also called bone tissue, that gives it rigidity and a honeycomb-like three-dimensional internal structure. Other types of tissue found in bones include marrow, endosteum and periosteum, nerves, blood vessels and cartilage. There are 206 bones in the adult human body^[8] and 270 in an infant.^{[9] [10]}

Cartilage[link]

A commonly mistaken thought is that Cartilage is only present in a human's nose area. However, when humans are first born, their skeletal structure is made entirely of cartilage. This substance is then replaced by bone around the age of 14 months. Cartilage is a stiff and inflexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle.

Cartilage is composed of specialized cells called chondrocytes that produce a large amount of extracellular matrix composed of Type II collagen (except Fibrocartilage which also contains type I collagen) fibers, abundant ground substance rich in proteoglycan, and elastin fibers. Cartilage is classified in three types, elastic cartilage, hyaline cartilage and fibrocartilage, which differ in the relative amounts of these three main components.

Unlike other connective tissues, cartilage does not contain blood vessels. The chondrocytes are supplied by diffusion, helped by the pumping action generated by compression of the articular cartilage or flexion of the elastic cartilage. Thus, compared to other connective tissues, cartilage grows and repairs more slowly. ^[10]

See also[link]

Wikimedia Commons has media related to: Skeletons

References[link]

External links[link]

Wikimedia Commons has media related to: Lymphatic system

• Skeletal, Bones and cartilage in great detail Human Body Skeleton, Bones and cartilage.

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (June 2011)

Andrew Maurice Gold (August 2, 1951 – June 3, 2011)^[1][2] was an American singer, musician and songwriter. His works include the Top 10 single "Lonely Boy" (1977), as well as "Thank You for Being a Friend" (1978), and "Never Let Her Slip Away" (1978).

Gold was a multi-instrumentalist, and he was also an artist, producer, film composer, session musician, actor, and painter.

Early life[link]

Gold was born in Burbank, California,^[1] and later joined a family business. His mother is singer Marni Nixon (who provided the singing voice for numerous actresses, notably Natalie Wood in West Side Story, Deborah Kerr in The King and I, and Audrey Hepburn in My Fair Lady); his father was Ernest Gold, the Austrian-born, Academy Award-winning composer for the movie Exodus.^[3] He has two younger sisters. Gold began writing songs at the age of 13.

Career[link]

1970–79[link]

By the early 1970s he was working as a musician, songwriter and record producer for many musicians. He was a member of the Los Angeles band Bryndle alongside Kenny Edwards, Wendy Waldman and Karla Bonoff. He played a major role as multi-instrumentalist and arranger for Linda Ronstadt's breakthrough album, 1974's Heart Like a Wheel, and her next four albums. Among other accomplishments, he played the majority of instruments on the album's first track, including the guitar work on "You're No Good," Ronstadt's first #1 single on the Billboard Hot 100, and the same on "When Will I Be Loved", "Heatwave", and many others. He was in her band from 1973 until 1977, and then sporadically throughout the 1980s and 1990s.

In 1975, Gold began recording as a solo artist, releasing four studio albums in the 1970s and over twelve since then. His hit single "Lonely Boy" reached #7 on the Billboard Hot 100 chart in June, 1977^[4] and has appeared in many film soundtracks, including Boogie Nights (1997) and Adam Sandler's movie Water Boy, among others. Although "Lonely Boy" was the bigger radio hit in the States, his single "Thank You For Being A Friend" (which peaked at #25 in 1978^[5]) later gained popularity as the theme song for the 1985–1992 NBC situation comedy The Golden Girls (performed by Cindy Fee for the show). Gold is also known for his biggest UK hit song "Never Let Her Slip Away", which was a UK #5 hit twice, by him and again at #5 fourteen years later by Undercover. Freddie Mercury, who was a friend of Gold's, assisted him with sparse harmony vocals as an uncredited background singer.^[6][7][8] Gold was pleased that Petula Clark covered "Lonely Boy" in French ("Poor Lonesome Playboy"). It is on her Paris, Orleans, Paris set. He attended one of her performances and reminded her that she had recorded the song. In 1976 Gold wrote the title track "Endless Flight" for Leo Sayer's hit album.

1975 also marked a successful collaboration with Art Garfunkel, playing most of the instruments on Garfunkel's solo hit "I Only Have Eyes For You" (which went to no.1 on the UK Singles Chart), as well as several other cuts on Garfunkel's album Breakaway, and Gold played guitar on two cuts of Eric Carmen's, Boats Against the Current album, including "She Did It", which was a #23 hit that same year.^[9] Throughout the years, he played and/or sang on records and/or live performances with Carly Simon, Jennifer Warnes, Stephen Bishop, Nicolette Larson, Maria Muldaur, Neil Diamond, Barbi Benton, Juice Newton, Leo Sayer, The Nitty Gritty Dirt Band, Karla Bonoff, Paul McCartney, Ringo Starr, John Lennon, Brian Wilson, Don Henley, Cher's hit album, Heart of Stone, wrote hits for Trisha Yearwood, Wynonna Judd, for whom he co-wrote the #1 single "I Saw The Light" with Lisa Angelle, whom he later produced on her own album. He toured with The Eagles, played on records and toured with Jackson Browne, produced, wrote and sang/played on three 10cc tracks; played and sang on record, and toured with James Taylor, produced singles for Vince Gill, and wrote and produced for Celine Dion; was second engineer on part of Joni Mitchell's Blue album.

1980–2011[link]

In the early 1980s, after 10cc's 1981 album Ten Out of 10 was completed, founding members Eric Stewart and Graham Gouldman invited Gold to become a member. Although he was a fan of "I'm Not In Love" and "The Things We Do for Love", and wanted to join, business conflicts prevented him from doing so. In late 1983, 10cc broke up, but Gold and Gouldman formed Wax. Wax recorded and toured for five years, enjoying success worldwide and had several top 10 hits including "Right Between the Eyes", and their biggest hit "Bridge to Your Heart". In 1986, interestingly, the duo had a #1 hit in Spain, lasting 6 months on top, and in a bizarre record company decision, no further singles were released there. The band broke up in 1989, but Gold and Gouldman continued to write and record together when possible.

During the 1990s Gold once again joined forces with bandmates Karla Bonoff, Wendy Waldman and Kenny Edwards to re-form Bryndle and release their first album. In 1996, he left Bryndle and released, Halloween Howls, considered by Dr. Demento as one of the two best Halloween albums in history.^{[citation needed]} The same year he recorded under a pseudonym, The Fraternal Order Of The All, "Greetings from Planet Love" on his own record label, QBrain Records. This album utilized a fake 1960s band, with original songs in the style of Gold's favorite 1960s bands, such as The Beatles, The Byrds and The Beach Boys. He released a rarities Wax album, Bikini Wax, and the same year he released ....Since 1951. He has since also produced, composed, and/or written songs for numerous films, such as the comedy Rectuma from director Mark Pirro and contributed songs for many television soundtracks and commercials. He sang "Final Frontier", the theme song for the television sitcom Mad About You. His rendition of the song was used as the wake-up call for the Mars Pathfinder space probe in 1996.^[10] Gold also produced seven albums for Eikichi Yazawa.

Personal life[link]

Gold married Vanessa Green, with whom he had three daughters, Emily, Victoria, and Olivia.^[3] After a divorce from Green, he married Leslie Kogan.^[3]

Although Gold put personal references in "Lonely Boy" (1977) including his year of birth, he admitted in an interview that it was not autobiographical: "Maybe it was a mistake to do that but I simply put in those details because it was convenient. I hadn't been a lonely boy at all – I'd had a very happy childhood."^[11]

In 1990, Gold and four of his family members competed on the game show Family Feud.^[12]

Death[link]

On June 3, 2011, Gold died in his sleep, apparently from heart failure,^[1] at age 59 in Los Angeles after having been treated for renal cancer.^[3][13]

Discography[link]

Albums[link]

• 1975: Andrew Gold
• 1976: What's Wrong with This Picture? (95 US)
• 1978: All This and Heaven Too (81 US)(#31 UK)^[14]
• 1978: An Interview with Andrew Gold [Promo-only interview & music LP]
• 1979: Whirlwind
• 1991: Home is Where the Heart Is
• 1996: ...Since 1951
• 1996: Halloween Howls (as Andrew Gold & Friends)
• 1996: Greetings from Planet Love (as The Fraternal Order of the All)
• 1997: Thank You for Being a Friend (compilation album)
• 1998: Leftovers
• 1998: Warm Breezes
• 2000: The Spence Manor Suite
• 2002: Intermission
• 2008: Copy Cat

With Wax

• 1984: Common Knowledge
• 1986: Magnetic Heaven
• 1987: American English
• 1989: A Hundred Thousand in Fresh Notes
• 1997: The Wax Files ('Best of' compilation)
• 2000: Wax Bikini (Compilation of outtakes, demos, etc.)

With Bryndle

• 1995: Bryndle

Singles[link]

• 1968: "Of All The Little Girls" (UK release - recorded as duo of 'Villiers & Gold')
• 1970: "Woke Up This Morning" (with the band 'Bryndle')
• 1975: "Heartaches in Heartaches"
• 1975: "That Is Why I Love You" (#68 US)
• 1976: "Stay"
• 1976: "Do Wah Diddy"
• 1976: "One Of Them Is Me"
• 1977: "Lonely Boy" (#7 US; #11 UK)^[14]
• 1977: "Go Back Home Again"
• 1978: "How Can This Be Love" (#19 UK)^[14]
• 1978: "I'm On My Way"
• 1978: "Thank You for Being a Friend" (#25 US; #42 UK)^[14]
• 1978: "Never Let Her Slip Away" (#67 US; #5 UK)^[14]
• 1979: "Kiss This One Goodbye"
• 1979: "Stranded On The Edge"
• 1979: "Nine To Five" (UK)

With Graham Gouldman as WAX;

• 1984: "Don't Break My Heart" (UK - Released under the band's initial name of World In Action)
• 1984: "Don't Break My Heart" (UK - Re-released under the band's subsequent name of Common Knowledge)
• 1985: "Victoria" (UK - Released under the band name of Common Knowledge)
• 1986: "Right Between The Eyes" (#60 UK )^[15]
• 1986: "Ball & Chain"
• 1986: "Shadows Of Love"
• 1986: "Systematic" (UK)
• 1987: "Bridge to Your Heart" (#12 UK)^[15]
• 1987: "In Some Other World" (UK & Germany)
• 1987: "American English" (Germany)
• 1989: "Anchors Aweigh" (UK)
• 1989: "Wherever You Are" (UK)

Some singles released as promo copies only; some chart numbers are from the magazines Cashbox and Record World.

References[link]

External links[link]

• Official website (Out of date)
• July 2011 Dublin City FM Radio Special