Mammalia

Author: Maggie Cussen
Mammalia

__**EXAMPLES**__: Horse

Rabbit

__**HABITAT**__: Mammals live in every biome on earth from the water, to the rainforest, to the tundra.

__**TYPE OF COELOM:**__ Mammals have two known coelomic cavities: Intraembryonic coelom: lined with somatic and splanchnic lateral plate mesoderm Extraembryonic coelom: lined with extraembryonic mesoderm.

All mammals have an endoskeleton, or internal network of bones and cartilage. Mammals are vertebrates meaning they have a spine located within the body.
 * __ENDOSKELETON or EXOSKELETON__:**

The central nervous system contains the brain, spinal chord, and retinas. The peripheral nervous system contains sensory neurons, ganglia, and nerves that connect to the central nervous system. The enteric nervous system independently controls the gastrointestinal system.
 * __TYPE OF NERVOUS SYSTEM__:**

__**FEEDER**__: Hoofed mammals are herbivores who graze with their teeth modified for foliage. Carnivores have long conical canine teeth to chew meat. Primates use opposable thumbs to grasp food and place it in their mouth. The Cetecea species (dolphins etc) have either teeth that strain large quantities of food or carniverous teeth.

__**SYMMETRY**__: Bilateral symmetry: equal on both sides of the body.

__**REPRODUCTION**__: Most mammals, except marsupials and monotremes, are placental, meaning instead of laying eggs the embryo continues to develop for a longer period inside the mother. The baby continues to receive nutrients through the placenta and is able to dispose of waste. Monotremes like the platypus lay eggs. Marsupials begin devolpment in the mothers body but are born in an immature condition. They continue to develop in the mother's pouch.

__**CIRCULATORY SYSTEM**__: Mammals have a closed circulatory system meaning the blood never leaves the network of arteries, veins, and capillaries. The circulatory system distributes blood and lymph.

__**ENDOTHERMIC or EXOTHERMIC**__. Mammals are endothermic (warm blooded). Hair is their form of insulation.

__**SEGMENTATION**__: None

__**WORKS CITED**__: "Coelom." //NDI Foundation//. NDI Foundation, n.d. Web. 29 Mar 2011. . Mader, Sylvia S. "Biology." Ed. Thomas C. Lyon. New York City: McGraw Hill, 2007. Print //Rabbit - Photo/picture Definition at Photo Dictionary - Rabbit Word and Phrase Defined by Its Image in Jpg/jpeg in English//. 2008. Photograph. //Internet FAQ Archives - Online Education - Faqs.org//. Web. 29 Mar. 2011. []. //Skips San Cat//. 2010. Photograph. Mayfield, KY. //Kentucky Lake Equine Hospital//. Web. 29 Mar. 2011. [].