Digestive system Alimentary Canal Of Cockroach

What Is The Digestive System And Alimentary Canal Of A Cockroach?

A cockroach has a well-developed digestive system, along an elongated coiled alimentary canal that portends into three divisions; the foregut, midgut, and hindgut.

The Foregut Of A Cockroach (Stomodaeum)

• The foregut of a cockroach consists of the buccal cavity, pharynx, oesophagus, crop, and gizzard.

• The food, after being properly softened by the mouth parts, enters the buccal cavity.

• Then the pharynx acts as a sucking pump and takes in the food through the oesophagus, which is connected with the crop.

• The crop is an organ of food storage that helps the cockroach store its food for digestion little by little.

• The proventriculus or gizzard has inner chitinous plates and thick-walled muscular, suitable for crushing the food into finer particles.

• Each salivary gland contains many branches, each of which has different secretions that run to a single tube.

• Both salivary glands have a reservoir that resembles a bladder as their salivary receptacle.

• These serve primarily as salivary secretion storage. A rectangular-shaped combined/common route that connects to the combined salivary passage is present in both receptacles.

• The combined salivary passage opens up the area of the mouth close to the labium. The entire foregut forms the lining of the chitin. The proventricular teeth and the plate are made by the chitin to aid in the process of food grinding.

The Midgut Of Cockroach(Mesenteron)

• The midgut is short compared to the foregut and is lined with glandular endoderm.

• There are eight blind globular hepatic caeca between the gizzard and midgut, which have digestive enzymes that secrete to help in the chemical digestion of food.

• The enzymes hydrolyze the complex molecules into simple ones so the body can absorb them.

The Hindgut Of A Cockroach (Proctodaeum)

• It consists of ileum, colon and rectum.

• The ileum is a short segment which ducts of Malpighian tubules, and excretory organs open into.

• The colon is a long thin segment and the rectum forms a short and wide segment opening out through the anus.

• The hindgut comprises the final phases of digestion, absorption of water and elimination of waste products.

Digestive Enzymes And Absorption

• The mouth, where the mandibles and maxillae help to chew the food, is where digestion first starts.

• Salivary carbohydrates, a component, partially digest food. Saliva lubricates the food and facilitates swallowing.

• The meal then travels via the oesophagus and onto the crop. This is the location where masticated food is temporarily stored.

• The gizzard, where the food is ground, would be the next location where it would move. At the intersection of the stomach and gizzard, there is a valve known as the stomodeal.

• This valve would provide smooth food transit in the stomach while preventing food regurgitation.

• The digestive enzymes produced by the gastric caeca handle the food once it reaches the stomach.

• The hepatic caeca and other caecal-type glands connected to the alimentary canal secrete digestive enzymes that act upon the complex food molecules and convert them into simpler molecules that can be absorbed; these include amino acids, monosaccharides, and fatty acids.

• The small molecules are then absorbed across the walls of the midgut and hindgut and then into the hemolymph, which is equivalent to the blood in cockroaches, to be circulated to the tissues of the body.

Malpighian Tubules And Excretion

• The excretory organs of cockroaches are the Malpighian tubules attached to the ileum.

• The tubules filter waste products from the hemolymph and carry them into the hindgut for expulsion outside through the anus.

• This also helps the cockroach maintain their water balance and ions in their body.

Dentition For Omnivorous Feeding

• Cockroaches are omnivorous, and hence they feed on a wide variety of food sources: plants, dead organic matter, and other insects.

• Their digestive system is well fitted to this type of diet.

• The crop stores food, the gizzard grinds it, and the midgut and hindgut further digest and absorb nutrients from various types of food.