Entomology Lecture Exam 2

What structures make up the Foregut?

esophagus, crop, proventriculus

What is the function of the Foregut?

storage, chemical and mechanical digestion

What structures make up the Midgut(= ventriculus)?

gastric caecae, peritrophic membrane, pyloric valve

What is the function of the Midgut(= ventriculus)?

chemical digestion, enzyme production, absorption, ion balance, immune response

What structures make up the Hindgut?

ileum, colon, rectum

What is the function of the Hindgut?

storage of wastes, nutrient reabsorption, osmoregulation, ion balance

What is the function of the Proventriculus?

Valve controlling entry of food into midgut and preventing midgut contents from moving back into the foregut

What can the Proventriculus look like?

muscular with sclerotized teeth, ridges, or spines for grinding food or reduced to simple flap-like valve

What is collected in the honeybee crop?

Nectar

What is the Proventiculus’ function in the honeybee?

prevents uncontrolled entry of nectar into the midgut

What marks the location of the pyloric valve in a honeybee?

The malpighian tubules

Explain the process of insect digestion

The peritrophic membrane wraps food particles

Initial digestion occurs inside peritrophic membrane

Leftover small molecules are digested in space between PM and the epithelial cells

Final digestion and absorption occurs at the surface of the epithelial cells

What system deals with metabolic waste management?

The excretory system

What’s the function of the excretory system?

expelling metabolic waste and maintaining water and ion balance

What are the 3 parts of the excretory system?

malpighian tubules, fat bodies, rectum

What is the function of the malpighian tubules in the excretory system and what are they analogous to in vertebrates?

uric acid, water, ion balance(excretion), analogous to the vertebrate kidney

What are the fat bodies in the insect excretory system analogous to in vertebrates?

the liver

What is the function of the rectum in the insect excretory system?

water re-absorption and ion balance (defecation)