*these animals are warm blooded, hairy and have mammary or milk producing glands.
*there are about 4.000 species of mammals found in world.
*they are the only animals which nourish their young once with milk.
*sebaceous glands(oil gland) and sudoriferous glands(sweat gland) are present in the skin.
*teeth are heterodont and thecodont(embedded in the shocket of jaws). they develop twice in a life hence it is diphyodont
*they possess a muscular diaphragm dividing trunk into thorax and abdomen.
*mammals possess seven cervical vertebrae, except few.
*the skull is dicondylic.
*the heart is four chambered.
*the coelom is divided into four cavities- a pericardial cavity, two pleural cavities and an abdominal cavity.
*12 pair of cranial nerve.
*each consists of three parts,external, middle and internal. pinna is a part of external ear
*a copulatory organ is always present.
*fertilization is internal.
*except egg laying animal they are viviparous.
*sub-class are Prototheria and Theria
*e.g.-kangaroo, opossum, human etc
*there are about 4.000 species of mammals found in world.
*they are the only animals which nourish their young once with milk.
*sebaceous glands(oil gland) and sudoriferous glands(sweat gland) are present in the skin.
*teeth are heterodont and thecodont(embedded in the shocket of jaws). they develop twice in a life hence it is diphyodont
*they possess a muscular diaphragm dividing trunk into thorax and abdomen.
*mammals possess seven cervical vertebrae, except few.
*the skull is dicondylic.
*the heart is four chambered.
*the coelom is divided into four cavities- a pericardial cavity, two pleural cavities and an abdominal cavity.
*12 pair of cranial nerve.
*each consists of three parts,external, middle and internal. pinna is a part of external ear
*a copulatory organ is always present.
*fertilization is internal.
*except egg laying animal they are viviparous.
*sub-class are Prototheria and Theria
*e.g.-kangaroo, opossum, human etc
OPOSSUM
HUMAN
KANGAROO
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