1. INSECT DIGESTIVE SYSTEMS

2. Insect Digestive System
Developmentally
cuticle 1 3 2
1. Foregut (stomatodeum) - ectodermal
2. Hindgut (proctodeum) - ectodermal
3. Midgut (mesenteron) - endodermal

3. FOREGUT
MIDGUT
HINDGUT

4. ventriculus
crop
pylorus
esophagus
rectum
pharynx
anus
cibarium
ileum
Malpighian tubules
salivary glands
gastric caeca
salivarium
proventriculus

5. Salivary Glands

6. Salivary Glands
Aphid
Blood feeders
Plant galls
Silk cocoons

7. Foregut
Cicada (Homoptera)

8. Salivary Pump Sagittal Section Frontal Section
Lumen of the salivary pump
Sagittal Section
Cibarial muscle
Frontal Section

9. Foregut

10. Proventriculus -
-grasshopper
intima

11. Peritrophic membrane
Secretion
Delamination

12. Peritrophic membrane
Membrane secreting cells
Secretion vesicles • • • • • • • • •
Peritrophic membrane • • • • • • • • • • • • • • • • • • • •
Invagination of stomatodeum

13. Midgut Enzymes - √ Insect Diet Protease Lipase Amylase Invertase
Maltase
Cockroach
omnivorous √
Carausius
phytophagous
Lepidoptera larvae
adults
nectar
Non-feeding
Lucilia
meat
Glossina
blood

14. Termites

15. Absorption of digested material
Malpighian tubule
caecum
Movement of H20
Movement of water, inorganic ions, sugars & amino acids

16. Absorption of digested material
Cicadas