What are fleas made of? - briefly
Fleas are built from a chitin‑based exoskeleton, internal organs, hemolymph, and a mixture of proteins and lipids that constitute their tissues. Their bodies contain roughly 60 % water, with the remaining mass formed by solid structural components.
What are fleas made of? - in detail
Fleas belong to the order Siphonaptera and are composed of typical insect structures adapted for ectoparasitism. Their bodies consist of an external cuticle, internal organs, and circulating hemolymph.
The outer shell is a hardened exoskeleton formed primarily from «chitin» interwoven with protein matrices. Sclerotization creates a rigid yet lightweight protective layer. The cuticle contains pigments such as melanin that give the insect its dark coloration.
Inside the exoskeleton, muscle fibers attach to the inner surface of the cuticle, enabling rapid jumps. The digestive system includes a foregut, midgut, and hindgut, each lined with epithelial cells that secrete enzymes for blood digestion. The nervous system comprises a brain, ventral nerve cord, and sensory ganglia that coordinate locomotion and host detection. Reproductive organs occupy the abdominal cavity, producing eggs that develop within the female’s body.
Biochemical composition reflects the insect’s physiology:
- Water: 70 %–80 % of total mass, maintaining cellular functions.
- Proteins: structural cuticular proteins, muscle actin and myosin, digestive enzymes, and hemolymph proteins such as vitellogenin.
- Lipids: membrane phospholipids, cuticular waxes, and energy reserves stored in the fat body.
- Carbohydrates: glycogen stores and chitin polysaccharide chains.
- Nucleic acids: DNA and RNA within all cells, supporting replication and gene expression.
Specialized mouthparts consist of a stylet composed of hardened «chitin» and cuticular proteins, allowing penetration of host skin and extraction of blood. The lack of wings is compensated by a powerful femoral muscle that stores elastic energy in the protein «resilin», releasing it to generate jumps up to 150 times the flea’s body length.
Overall, fleas are constructed from a chitinous exoskeleton, muscular and nervous tissues, digestive and reproductive systems, and a biochemical matrix dominated by water, proteins, lipids, carbohydrates, and nucleic acids. This composition enables survival as agile, blood‑feeding parasites.