Question

WRITE ABOUT A THEME: ORGANIZATION Write a short essay(100–150 words) that explains how the structure of the digestive tract in different invertebrate groups affects the size of the organisms that they can eat.

Short answer

Invertebrates like sponge and cnidarians have a central body cavity rather than a digestive tract. This central cavity of sponges is lined with cells that use phagocytosis to take food particles from the water pulled into the cavity.

This cavity enables the consumption of comparatively small creatures. On the other hand, Cnidarians push trapped prey into their central cavity, where it is digested into components that can be absorbed by the cavity's cells. This enables the consumption of relatively large creatures.

Step-by-step solution

Invertebrate organisms

Invertebrates are organisms that do not possess a vertebral column. More than 90 percent of the living animals are invertebrates. Pests, parasites, and carriers of parasitic diseases to humans and other vertebrates are essential in agriculture for invertebrates.

Digestive tract of invertebrate organisms

The most straightforward invertebrate digestive system is made of one opening that serves as both anus and mouth for digestion and excretion. Many invertebrates utilize extracellular digestion; however, a few taxa can use both intracellular and extracellular digestion.

The structure of the digestive tract may affect the size of organisms the invertebrates eat

Living beings have developed various kinds of digestive systems according to the type of foods they eat. The digestive system of invertebrates is simplest, with one opening or the gastrovascular cavity.

The gastrointestinal tract thus determines the size of organisms they consume. The invertebrate digestive tract mainly consumes small animals depending on the pathway for the digestion of food.

Thus, the size of the organisms consumed depends on the structure of the digestive tract in invertebrates.