Annelida
Important Information
Earthworms (Lumbricus Terrestris)
The earthworm has a simple but sensitive nervous system. the brain (cerebral ganglion) is connected to the ventral chord which runs along the body. Each segment must link together to move and to control the muscles. The earthworm is sensitive to touch, light, chemicals, temperature, and vibrations.
Leeches (Hirudo Medicinalis)
The leech has a similar nervous system to that of the earthworm. The leech has a brain also called the ganglion, one located in the anterior and one located in the posterior which are connected by the ventral chord which runs along the body. The leech does not have eyespots to sense light.
Roundworms(Caenorhabditis elegans):
The roundworm has a very simple nervous system. The nervous system is composed of two nerve chords that transmit impluses around the roundworm.
- Variety of sensory cells.
- Touch cells, or mechanoreceptors, contain hairs which help sense objects.
- Earthworms also have light sensitive cells.
- Cells are abundant in the anterior and posterior.
- Mostly located in the first five segments.
- Also they have taste cells.
- Each segment has nerves the receive impulses from the sensory cells.
- It has a ventral nerve chord and a brain.
Earthworms (Lumbricus Terrestris)
The earthworm has a simple but sensitive nervous system. the brain (cerebral ganglion) is connected to the ventral chord which runs along the body. Each segment must link together to move and to control the muscles. The earthworm is sensitive to touch, light, chemicals, temperature, and vibrations.
Leeches (Hirudo Medicinalis)
The leech has a similar nervous system to that of the earthworm. The leech has a brain also called the ganglion, one located in the anterior and one located in the posterior which are connected by the ventral chord which runs along the body. The leech does not have eyespots to sense light.
Roundworms(Caenorhabditis elegans):
The roundworm has a very simple nervous system. The nervous system is composed of two nerve chords that transmit impluses around the roundworm.