Insects insects (from Latin insectum)are pancrustacean hexapod invertebrates of the class Insecta
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ExternalInsect morphology A- Head B- Thorax C- Abdomen antenna ocellus (lower) ocellus (upper) compound eye brain (cerebral ganglia) prothorax dorsal blood vessel tracheal tubes (trunk with spiracle) mesothorax metathorax forewing hindwing midgut (stomach) dorsal tube (Heart) ovary hindgut (intestine, rectum, anus) anus oviduct nerve cord (abdominal ganglia) Malpighian tubules tarsal pads claws tarsus tibia femur trochanter foregut (crop, gizzard) thoracic ganglion coxa salivary gland subesophageal ganglion mouthparts Insects have segmented bodies supported by exoskeletons, the hard outer covering made mostly of chitin. The segments of the body are organized into three distinctive but interconnected units, or tagmata: a head, a thorax and an abdomen.[60] The head supports a pair of sensory antennae, a pair of compound eyes, zero to three simple eyes (or ocelli) and three sets of variously modified appendages that form the mouthparts. The thorax is made up of three segments: the prothorax, mesothorax and the metathorax. Each thoracic segment supports one pair of legs. The meso- and metathoracic segments may each have a pair of wings, depending on the insect. The abdomen consists of eleven segments, though in a few species of insects, these segments may be fused together or reduced in size. The abdomen also contains most of the digestive, respiratory, excretory and reproductive internal structures.[36]: 22–48 Considerable variation and many adaptations in the body parts of insects occur, especially wings, legs, antenna and mouthparts. Yüklə 204,5 Kb. Dostları ilə paylaş:
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