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Use this page to view Mario's nervous system. For details about spinal cord, see the "spinal cord" page off of the home page .

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The Crayfish is a invertebrate but still has a brain and nerves. The only thing it lacks compared to the pig and frog is a spinal cord.

The body of the crayfish is separated into two different regions. The first region, known as the cephalothorax, is where the activities such as sense, locomotion and feeding are controlled amd the second region, called the abdomen, where ocomotor and visceral functions are controlled.


===The Brain

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--> the following pictures were obtained from http://www.science.smith.edu/departments/NeuroSci/courses/bio330/labs/LAanatomy.html

If one were too look at the brain of the crayfish closely this is what it would appear to be.
If one were too look at the brain of the crayfish closely this is what it would appear to be.

If one were too look at the brain of the crayfish closely this is what it would appear to be.
Fig. 1.1





This picture labels the brain of the crayfish showing that it though it is small it is still complex.
This picture labels the brain of the crayfish showing that it though it is small it is still complex.


Fig. 1.2


===The Nerves

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Internal anatomy of a crayfish
Internal anatomy of a crayfish

http://www.infovisual.info/02/025_en.html

As one can view from the picture above, many of Mario's major nerves are located on his ventral side, the name is a
give away. It is upon this ventral cord, that only runs through the anterior of Mario, that the ganglions are located,
it is also known as the subesophageal.
"The crayfish nervous system is composed of a ventral nerve cord fused with segmental ganglia, and the supresophageal
and subesophageal ganglia. Giant neurons in the ventral nerve cord function in escape responses. The supraesophageal
and sub esophageal ganglia control the head appendages in response to sensory input received from receptors"
http://www.science.mcmaster.ca/Biology/Harbour/SPECIES/CRAYFISH/CRAYFISH.HTM#Nervous

The encephalon, which is located right next to the eye and connects right off of the ventral nerve cord, is where the mental
functions take place. The encephalon is what is identified as the brain, one can see pictures of Mario's brain above
( Fig. 1.1 and Fig. 1.2). The brain, like thatof the pigs, is divided into many different sections that control different movements
and actions of Mario. The encephalon is also known as supraesophageal ganglion.