MUSCULAR

MUSCULAR SYSTEM: The muscular system is the anatomical system of a species that allows it to move.

Overall importance to the skeletal system:

• provides movement for animals
• structuralism alongside skeletal system.
  
• made up of proteins
• organ system
• provides circulation for the body
• vertebrate
• invertebrate
• controlled by nervous system
• movement of muscles comes from ATP energy (adenosine triphosphate)

Evolutionary advantage/disadvantage:

EARTHWORM: the earthworm has a tunnel structure filled with what looks like different cords throughout its body acting like its muscular system, the advantages to having the hydro-static body shape and movements lets the muscles do less work, using less energy. Because of the body structure and simplicity of its insides and outsides has let it advance in the evolutionary scale. Disadvantage to having a free all over muscular system is that its not very sturdy and its a lot less complex then the frog or rat, its easy to tear them or against predators they are no match. They have no protection and no strength to fight back. 

CRAYFISH: The muscular system of crayfish includes powerful abdominal muscles that make it possible to swim backwards giving a huge evolutionary advantage over other marine species because it can move quickly if threatened by a predator, containing the same strong muscles in its claws, tail, mandibles and legs. evolutionary the crayfish has the second formed type of muscular system and it has successfully been able to pass on its traits. disadvantages to having this muscular system is that its easily able to be destroyed and broken, and only having this power in the tail and claws doesn't give it much of a defense for itself. 

GRASS FROG:  having quick and powerful movements the frogs muscular system gives it an advantage to a long distance get away and to keep moving longer distances to evade predators. its abdominal muscles act like a thick bouncy cushion against the hard ground when it lands off of a jump, giving it protection for the insides of its organs. disadvantage to powerful muscles is needing to generate the energy by constantly needing to feed on the diet to keep going, putting the frog in potential danger to get its next meal. 

WHITE RAT: A very flexible muscular system of many layers gives the rat the advantage to move quickly, and a flexible spinal cord allows it to get through the tiniest odd places. it has the top evolutionary advantage because its build very similar to humans. Obvious disadvantages like us is broken bones, torn muscles and if its diet changes or diminishes the body will drastically be effected. 

differences and commonalities between creatures: 

EARTHWORM:

• segmented
• free muscular system
• not thick
• provides its movements
• not powerful
• no protection

CRAYFISH:

• muscles in tail
• propulsion
• provides movements
• free muscular system
• little protection

GRASS FROG:

• all in abdominal and legs
• used for cushion
• powerful
• like humans muscles

WHITE RAT:

• like human muscle system
• all over body
• creates movements
• strong legs
• tail used for balance
• 4 feet more movements and faster
• increased defense against broken bones