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INTRODUCTION

The term of insects is derived from the Greek words entomon’ insects and logos ‘means to study agricultural entomology deals with the study of insects.they belong to the phylum Arthropoda, which includes animals with jointed legs, segmented bodies insect play important roles in ecosystems such as pollination decomposition and as part of food chain.

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DEFINITION OF INSECTS 🦋

Insect is tracheat Arthopods

They have

  • Segmented body
  • Grow by molting
  • Body cavity filled with blood
  • Dorsal heart with valve like ostia
  • Dorsal brain with ventral nerve cord
  • Paired, segmented appendages
  • Tubular alimentary cannal with mouth and anus at anterior and posterior ends.

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CHARACTERS OF INSECTS

  • Body divided into 3 segment: head,thorax and abdomen.
  • Posses three pair of legs,hence the name hexapoda
  • Presence of one or two pairs of wings
  • A pair of antennae
  • Respiration by means of internal air tubes know as trachea
  • Presence of meta morphosis (in complete/complete) during development

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POSITION IN ANIMAL KINGDOM

Kingdom - Animal

Phylum - Arthropoda

Class - Insecta

Order - Lepidoptera(butterfly,moths)

Family - Noctuidae

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Why insect are in class insecta?

  • Presence of 3 body parts
  • 3 pairs of legs
  • Tracheal respiration
  • Development through metamorphosis

Example of insects

Butterfly,Ant, housefly, mosquito, Beetle

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IMPORTANCE OF INSECTS

  • Pollination (eg:bees🐝)
  • Biological control to manage harmful pests
  • Some are pests and disease vector
  • Useful products like honey,silk,wax and lac
  • Helps in decomposition of organic matter (clean environment)
  • Play a key role in food chains for birds and animals
  • Agricultural importance improve soil aeration ants and beetles
  • Insect are used in research and experiment genetic studies

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