what is a squid?

Answer 1

here is some info....
Squid, a carnivorous mollusk belonging to the same class as the nautilus, cuttlefish, and octopus (see Cephalopod).

The squid has a large head and a relatively large brain. Its body, stiffened by an interior cartilaginous skeleton, is spherical or cigar-shaped, with two lateral fins. Around the mouth are eight sucker-bearing arms and two contractile tentacles with spatulate tips; on the latter are four rows of suction cups encircled by rings of chitinous (horny) hooks. The contractile tentacles, longer than the rest, are used to seize the prey and pass it to the shorter arms, which hold it to be torn by strong jaws shaped like a parrot's beak. Squid can swim faster than any other invertebrate by rapidly expelling water from the mantle cavity through the “funnel,” which can be turned to direct movement. Many deep-sea squid are bioluminescent. They shoot out a cloud of dark ink when pursued; one genus secretes luminescent ink.

In the male squid, one smaller arm is modified for the purpose of planting a packet of sperm (a spermatophore) in the female's oviduct. In some squid, such as the common squid of the east North Atlantic coast, the sperm can also be deposited in a vesicle below the female's mouth; the spermatophore, already opened by the male, releases the sperm as the eggs are produced. The females fasten their eggs to seaweed or to the ocean bottom by a viscous filament. The eggs of deep-water squid are free-floating.

Squid species vary greatly in size. The common squid of the east North Atlantic coast is 30 to 45 cm (12 to 18 in) long, and the giant squid, at least 18 m (60 ft) long, is the largest aquatic invertebrate. It lives at depths of 300 to 600 m (985 to 1970 ft), where it is the prey of sperm whales.

Scientific classification: Squid belong to the order Teuthoidea of the class Cephalopoda. Squid that secrete luminescent ink are classified in the genus Heteroteuthis of the family Sepiolidae. The common squid of the east North Atlantic coast belongs to the family Loliginidae and is classified as Loligo vulgaris. The giant squid is classified in the genus Architeuthis of the family Architeuthidae.

Answer 2

Any of nearly 400 species of 10-armed CEPHALOPODS, found in both coastal and oceanic waters, that prey on fishes and crustaceans. They range from less than 0.75 in.(1.5 cm) to more than 65 ft (20 m) long(in the case of the giant squid). Two of the 10 arms are long, slender tentacles, each has an expanded end and four rows of suckers with toothed, hard-edged rings. An internal shell supports the slender tubular body of most species. Squid eyes, almost as complex as human eyes, are usually set into the sides of the head. Squids may be swift swimmers(propelling themselves by contracting and relaxing their mantle or by undaulating their two fins) or mere drifters; water expelled from a funnel below the head can propel the squid back. Like the octopus , the squid may emit an inky cloud from its ink sac when in danger from sperm whales, fishes or humans, among other predators.

Answer 3

A squid is an seafaring animal which has no skeleton, and looks a bit like a jellyfish or octopus.
It also squirts and inklike substance from glands near it's rectum when it senses that it may be in danger. This is a defense mechanism used to temporarily blind it's would-be predator and allow time for escape.

Answer 4

A squid is a mollusk with tentacles.
Squid, octopus, chambered nautilus, cuttlefish are the kind of mollusks called cephalopods.

Answer 5

Here's a picture of a Caribbean reef squid:

http://en.wikipedia.org/wiki/Image:Caribbean_reef_squid.jpg