Urinary system The kidneys are bean-shaped organs which are present on each side of the vertebral column in the abdominal cavity.
The anal cerci are possibly the relics of last abdominal appendages Fig.
The styles of male and the gonapophyses are possibly relics of appendages. Insertion of muscles occur through tendons in many cases. Body Cavity of Cockroach: The embryonic blastocoel and coelom unite to form the adult body cavity, known as haemocoel.
Two types of cells—bi-nucleated and with elongated nucleus, are present in the fat bodies. The cells are derived from the walls of the embryonic cavities. Digestive System of Cockroach: The alimentary canal is divided into three zones: The foregut or stomodaeum starts from mouth, ending in gizzard.
It is lined by cuticle: Ventral in position, located at the base of the buccal cavity. A short, vertically oriented tube, opening into the oesophagus. There is no demarcation between the oesophagus and crop.
In fact, the crop is a large, sac-like dilatation of oesophagus. It extends into the abdomen. The crop acts as a temporary reservoir of food, where it can be retained for about 60 days. A round, thick- walled, muscular structure, posterior to the crop. A narrow tube, running from the gizzard to the hindgut.
A narrow tube, divisible into three zones — ileum, colon and rectum.
The junction of the mid and hindgut is marked by 60 to 70 extremely fine, yellowish Malpighian tubules. The tubules are excretory in function. The rectum is sac-like, bearing papillae on the inner wall. Rectal glands in the wall absorb water and salt and help in osmoregulation. It consists of two salivary glands and two receptacles with their ducts Fig.
The glands and the receptacles Fig.
Each gland consists of two leaf-like glands, made of diffused lobes. The receptacles are elongate oval sacs, the anterior ends being narrower. The ducts from the two glands unite and those from the receptacles also unite to form two common ducts, which again unite and form an efferent salivary duct opening on the ventral side of the hypo pharynx.
The caeca are about one-third of the midgut in diameter and open in it.The malpighian tubules of insects Although some terrestrial arthropods (e.g., land crabs, ticks) retain the coxal glands of their aquatic ancestors, others, the insects, have evolved an entirely different type of excretory system.
Excretory System The Malpighian tubules perform the excretion in a cockroach. There are glandular and ciliated cells that are present lining each tubule, which absorb the nitrogenous waste products.
Excretory System of Cockroach: 1. The excretory organs consist mainly of numerous Malpighian tubules and nephrocytes (Fig.
). 2. The Malpighian tubules are thread-like yellow structures of variable number present at the junction of the mid and hindgut. ADVERTISEMENTS: The following points highlight the top seven types of excretory organs in invertebrates. The types are: 1. Contractile Vacuoles in Paramoecium 2.
Excretory System of Planeria (With Reference to Flame Cells) 3. Excretion in Taenia Solium 4. Excretion in Earthworm with Reference to Nephridia 5. Excretion in . The efficiency of the excretory system of the American cockroach was measured using a dye clearance test.
Indigo carmine in aqueous solution was injected into the blood and the rate of its removal was checked by densitometric measurements of blood spots on filter paper strips. 7. Excretory System of Cockroach: The main excretory organs of the cockroach are the Maipighian tubules which float in the hoemocoelic fluid.
The number of tubules vary from sixty to seventy. Each tubule is a hollow outgrowth from the proctodaeum and is lined by glandular epithelium which secretes nitrogenous waste products.