The Digestive System
The digestive system of the worm consists of the mouth, the Pharynx, the esophagus, the crop, the intestine, and the gizzard.
The food enters the mouth and is swallowed by the pharynx. After, the food (ex. dirt) gets passed through the esophagus to the crop where it is stored and then after some time it will get moved into the gizzard. In the gizzard stones that the worm ate to crush/ grind up the food completely. Then the food is digested and absorbed in the intestine. |
The Circulatory System
The phylum annelida has a closed circulatory system (A system in which blood circulates the body in closed vessels and is confined to them.) The circulatory system circulates needed blood, nutrients, and gasses through the series of blood vessels.
Two vessels that circulate the nutrients and gases are called the dorsal and ventral blood vessels. The dorsal vessel is where the blood is circulated to the front sections of the annelida. The ventral blood vessel is when the blood circulates to the back of the body and gives the body wall and the intestine with blood. The ventral vessel has many different branches. Then the branches split into capillary beds to get and release the nutrients and oxygen supplied through the vessels
The Nervous System
Annelida has a central nervous cord that goes from the brain down the whole body, where it communicates important information from sensory organs and other important things, such as locomotion. It also has many cerebral organs that are connected to the central nerve.
It also has many brains along it's segments that are connected through one main nerve cord, that transmits sensory data. |
Interesting Things
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