INTEGUMENTARY

INTEGUMENTARY SYSTEM: the system in which there is some sort of body covering on an organism. weather it be skin,scales or mucus.

Overall importance of the integumentary system:

• helps to provide circulation throughout organism to keep organism alive. 
• the body covering helps to maintain Homeostasis: body temperature, lubrication ect.
• provides efficient protection for organisms against outside forces such as weather and predators. 
• contains a product called melanin: derived from the amino acid tyrosin which provides pigment in animals.
• the integumentary system is made up of 3 layers in mammals and humans: Epidermis, Dermis, and Sebaceous layer.

evolutionary disadvantages and advantages:

It is crucial in survival that all organisms have a body covering no matter what it is, If you don't have one your at a larger disadvantage to others because of the lack of having a shield against factors that cause harm to the body and its insides and not being able to have a sufficient way to have adaptations to there environment causing the survival to go down. With the two sub-types of  body coverings Endothermic (containing your heat within) and Ectothermic (having your environment provide your body temperature for you), being without skin causes a lot of problems. With endothermic covering it may be easier to keep yourself warm due to being warm blooded, but on the other hand your far more susceptible to increased sensitivity to what your environment throws at you. Ectothermic or being cold blooded has its positives and negatives, the organism lives in the perfect environment and it helps maintain homeostasis and continue to thrive but as soon as something changes the organism must adapt quickly always having to live in warm places to keep healthy. Millions of years ago all that was on earth were fish, sea life and small forms of reptiles. concluding from that I know that the function of the ectothermic system evolved first. In a simple organism such as the earthworm the integumentary system works for only two reasons, to breath and to move. In a more complex organism such as the rat it provides protection, adaptations survival, body temperature regulations and is passed down from parents in its heredity. 

simalarities depending on color between organisms:

EARTHWORM: 

• body is segmented to provide easier movement 
• slimy body covering provides almost another layer of protection and used for movement
• containing only two layers of very thin skin to allow for diffusion (is the movement of molecules from an area of higher concentration to an area of lower concentration)
• Setae or bristles alongside the underbelly of worm are like feet and hands to grab and move to prevent sliding.
• having no respiratory system the earthworm breathes through its skin.

CRAYFISH:

• exoskeleton that is hard and bumpy provides protection
• contains melanin that gives the crayfish its color
• shell provides structure acting like its skeletal system as well.
• not permeable 

GRASS FROG:

• frogs do not have the subcutaneous layer of skin.
• contains large sums of melanin
• skin designed for camouflage and survival
• mucus all over body of frog provides lubrication to escape from prey ad to move easily in water.
• frogs drink through permeable skin along with respiration and protection.

WHITE RAT:

• skin on face contains whiskers
• like humans there skin has  layers
• helps to regulate body heat
• also contains melanin
• gets rid of waste through pores.
• skin is permeable