Development of Adrenal Gland in animals The origin of adrenal gland is of double origin. The gland develops in the intermediate mesoderm at the cranial pole of the mesonephric kidney. The adrenal cortex is derived from the surrounding intermediate mesoderm and he adrenal medulla is ectodermal in origin, being formed by cells derived from the neural crest.

Development of Urinary System in animals The urinary and genital system both arises from the mesoderm. Both drain into a common urogenital sinus and hence these two systems are intimately associated in their origin, development and relation. Development of Urinary organs Nowhere in the development of the individual can be found a better example of

Development of Respiratory System of Animals The epithelium of respiratory tree is derived from endoderm. The primordium of this system is the laryngo-tracheal groove, which runs lengthways in the floor of the foregut just behind the last pair of pharyngeal grooves. On the ventral surface, the endoderm projects as a ridge. This ridge is the primordium

Development of Digestive System of Animals The digestive tube consists of an internal tube of endoderm which is the primary tissue that becomes the epithelial lining and an investing layer of splanchnic mesoderm that specializes into the connective tissue, muscle and peritoneum. The primitive gut is made up of three portions, the foregut, midgut and

Development of Tongue of animals The tongue of animals develops from the ventral ends of the branchial arches. It consists of two parts oral and pharyngeal. The oral part is the body occupying the mouth cavity and arises from the mandibular arches in front of the oral membrane and hence is covered by ectodermal epithelium.

Development of Teeth of animals Development of Teeth of animals take place by the both ectoderm and mesoderm. A tooth is a highly modified connective tissue papilla that has undergone a peculiar ossification into dentine and caged by hard enamel elaborated from the epidermis. In addition the cement a bony deposit encrusts the base. The

Development of Pituitary Gland in animals The hypophysis cerbri or pituitary gland is an ectodermal derivative and an endocrine gland of double orgin. One part glandular in nature is derived from the epithelium of the stomodeum while the other not so plainly secretory is a specialized extension from the brain. A dorsal evagination the Rathke’s pouch from

Development of Periphery Nervous System The neural crest cells form the ganglionic elements and supporting structures of the peripheral nervous system. The neural crest cells migrate from the dorsal midline. Some of the crest cells aggregate dorsolateral to the aorta forming sympathetic trunk ganglia. Other crest cells continue to migrate ventrally to form abdominal sympathetic

Development of Central Nervous System / CNS Development of Nervous system The primordium of the nervous system is one of the first structures to appear in the embryo. A thickening of the dorsal ectoderm called neural plate develops first along the mid dorsal line of the embryo. By unequal growth the neural plate is folded

Development of Face (Mouth, Lips and Gums, Cheeks, Palates) Development of face The stomodeumor the primitive buccal cavity is formed by the formation of the cranial and lateral foldings and subsequent cranial flexures. It is separated from the pharyngeal cavity by the oropharyngeal membrane which breakdown following the fusion of the left and right mandibular processes.