Entomology Quiz: Insect Behavior and Digestive System

Insect Capture and Parasitism

• Insects can capture prey by speed in pursuit, trapping, or using modified appendages
• Parasites live off a host without killing it, with ectoparasites living externally and endoparasites living inside
• Blood-sucking insects can be ectoparasitic for a long period or only while feeding

Digestive System

• The insect alimentary canal can be divided into three sections: foregut, midgut, and hindgut
• The foregut consists of the oral cavity, salivary glands, pharynx, oesophagus, crop, and gizzard
• The midgut consists of the ventriculus and caecum
• The hindgut consists of the anterior hindgut, rectum, and valves
• Waste products are emptied via Malpighian tubules into the alimentary canal at the beginning of the hindgut

Larval Forms

• Larvae of butterflies or moths have oligopod larvae with only three pairs of sclerotized, jointed legs
• Apod larvae have no legs
• Larvae of many ants, bees, wasps, and flies (maggots) have no legs

Pupal Forms

• Obtect pupae have appendages fused to the body
• Exarate pupae have appendages free from the body
• Coarctate pupae are contained within the last larval exoskeleton, the puparium

Diet and Feeding

• Diets can be classified as saprophytic, phytophagous, or carnivorous
• Saprophytic insects consume plant or animal remains
• Phytophagous insects feed on plant parts, with mouthparts adapted for chewing, piercing, and sucking
• Carnivorous insects consume animal tissues and may be used as biological control agents

Respiration

• Insects have a waterproof cuticle, but some live in moist areas and are sedentary with permeable cuticles
• Most insects have a special respiratory system comprising a system of internal tubes, called trachea
• Air enters from the outside through a series of openings, spiracles, which are typically located on the thorax and abdomen
• Aquatic insects have adapted respiratory systems, such as tracheal gills or hemoglobin in their blood
• Some aquatic insects have hydrofuge hairs to break the surface tension of the water and keep water out when underwater

Test your knowledge of insect behavior, including predation, parasitism, and parasitoidism, as well as the different sections of an insect's digestive system. Learn about ectoparasites, endoparasites, and more!