Physical characteristics

The basic body structure of onychophorans is a simple one, but it is a design that works well. They have changed little in appearance over the last 500 million years. Onychophorans have a soft and flexible cylindrical body that is slightly flattened on the ventral side. The head bears a pair of annulated antennae with beady eyes located at their bases and a ventral circular mouth, equipped with fleshy lips and paired jaws. On either side of the mouth is an oral tube, sometimes called the "oral papillae." Paired legs, the oncopods, extend along the full length of the body and vary in number (depending on the species) from 13 to 43 pairs. The genital opening is on the ventral side at the posterior end of the body, and they have a terminal anus. Each oncopod is a conical, unjointed appendage with a foot that bears a pair of terminal claws. There are three to six spinous pads on the underside of each oncopod at the base of the feet, and often in males a crural, or pheromone-secreting, gland on the underside of some or all of the on-copods, close to their junction with the body. The body is covered by a thin cuticle that is molted at regular intervals. The cuticle is adorned with papillae, each composed of overlapping rows of scales. The largest papillae bear sensory

A velvet worm (phylum Onychophora) on a forest floor in Ecuador. These creatures have been described as the missing link between annelids and anthropods. They live only in humid, dimly lit places, and are primarily nocturnal. (Photo by Dr. Morley Read/Science Photo Library/Photo Researchers, Inc. Reproduced by permission.)

A velvet worm (phylum Onychophora) on a forest floor in Ecuador. These creatures have been described as the missing link between annelids and anthropods. They live only in humid, dimly lit places, and are primarily nocturnal. (Photo by Dr. Morley Read/Science Photo Library/Photo Researchers, Inc. Reproduced by permission.)

bristles. It is these sensory papillae that give onychophorans their velvety appearance and common name, "velvet worms."

Apart from a few white, cave-dwelling species, they are generally blue-gray or brownish in color, often intricately and beautifully patterned, with stripes, diamonds, spots, or chevrons.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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