Invertebrate Zoology

Balanoglossus is a hemichordate. The excretory organ in Balanoglossus is glomerulus. This is also known as the proboscis gland. This gland is present in front of the central sinus. The gland projects outward in the proboscis coelom. The gland is comprised of many tube like projections. The tubes are blind at one end. The tubes are formed by the peritoneum. They are present as the covering of buccal diverticulum, central sinus, and heart vesicle. This organism is considered as the link between vertebrates and invertebrates. 

The wheel organ is found in amphioxus, which is a specialized epithelium in the roof and sides of the adult lancelet oral cavity. It borders the oral epithelium proper. The wheel organ cells are tall and strongly ciliated and have dark, heterochromatin-rich nuclei. It draws food through the use of its cilia for digestion. 

The crop also called as honey stomach or honey sack is a specialized part of foregut. It is similar to distensible sack. The main function of the crop is transport and storage of liquid food (water, nectar and honeydew). Another function of crop is uptake of water from its lumen. 

Pseudopodia, are the locomotory organs, which are mainly present in the prokaryotic cell or the unicellular protist. These are cytoplasm filled temporary projections. These are also used for the process such as phagocytosis. It is also used in major mechanism to remove pathogens and cell debris e.g.,

Amoeba.

The typhlosole is a median internal fold of the intestine in earthworms (Pheretima) that significantly increases the surface area for the absorption of digested nutrients.

The alimentary canal of grasshopper is divided into three main portions as

• Foregut
  
• Midgut
  
• Hindgut
  

The digestion in sponges is intracellular. It takes place in coenocytic oral cells. The movement of water initiated by the coenocyteS. It helps in the digestion and respiratory system of sponges because along with the water they also transport oxygen. They then push out carbon dioxide which is a waste material out of the sponge body.

Grasshoppers have the typical insect body plan of head, thorax and abdomen.
 The thorax and abdomen are segmented and have a rigid cuticle made up of overlapping plates composed of chitin. Hence, Wall of a crop is muscular and its lumen is lined with cutile is wrong about the digestive system of a grasshopper.

Termites depend on protozoans which digest the cellulose ingested from the dead wood. Protozoa will die outside the termite and termite unable to digest the food without protozoans, hence they were in a symbiotic relationship.

• The function of fungal part of a lichen is the absorption of water and minerals from the substratum and providing protection for the phycobiont.
• Food production is done by phycobiont.
• So, the correct answer is 'Absorption of minerals and Protection'.

During its lifecycle, the infective juvenile or rhabditiform larva of Ascaris migrates through the bloodstream to the heart and lungs. It undergoes its second and third molts inside the alveoli of the lungs before moving up the trachea.

The liver is a metabolic and detoxification organ. While it processes waste for excretion, it is not classified as an excretory organ in the same sense as the kidneys, lungs, or skin.

Insects breathe through a system of tiny openings along their thorax and abdomen called spiracles. These lead to a network of tubes called tracheae that deliver oxygen directly to tissues.

Insects have six legs and three body regions (head, thorax, and abdomen), whereas arachnids have eight legs and two body regions (cephalothorax and abdomen). Therefore, both the number of legs and body division differ between them.