Grasshoppers eat green vegetables and foliage. Food is crushed by the mandible and maxilla. Then it is slippery mixed with lalars. Digestion of food by different parts of the alimentary canal is discussed below-
1. Digestion in crop: Food mixed with saliva is broken down into small particles due to contraction and expansion of the crop wall. Carbohydrates are converted into glucose by amylolytic (invertase, maltase, lactase) enzymes. Proteins are converted into amino acids under the influence of proteolytic (trypsin, protease, peptidase) enzymes. Lipolytic enzymes convert lipids into fatty acids and glycerol.
2. Digestion in the gizzard: As a result of the contraction and expansion of the gizzard, the food becomes very small particles.
3. Digestion in the Mesentery: Various enzymes are secreted from the hepatic caeca of the mid alimentary canal. All these enzymes digest food.
(i) Proteins are broken down into peptides under the action of trypsin enzyme. The peptide is then broken down into amino acids with the help of the enzyme eropsin.
(ii) Sugars are broken down into maltose under the action of amylase enzyme. Maltose is then broken down into glucose with the help of maltase enzyme.
(iii) Lipid is broken down into fatty acids and glycerol by the action of lipase enzyme.
Absorption of nutrients
The walls of the mesentery and hepatic ceca contain absorptive cells. These cells absorb most nutrients. Most of the glucose is absorbed in the hepatic cecum. The rectal wall absorbs excess water, minerals and amino acids from the stool. Grain-shaped feces are excreted in the anus. Dr. Siddiq Publications