ANATOMY-DUCTS and CANALS IN ANIMALS

ANIMAL ANATOMY- CANALS AND DUCTS THEIR POSITION AND FUCTIONS

perversely  i discussed about various exocrine glands in and foramen in animals .This topic coves about various principle ducts and canals present in animal body and their location and their functios.

ANAL CANAL
Location: Rectum of Mammals 
Function : It extends from the pelvic floor downward and posteriorly to the anus.

BIDDER’S CANAL
Location: Frog’s kidney sperms.
Function : It connects testis to kidney and conducts

BILE DUCT
Location: Vertebrates
Function : It runs from gall bladder to duodenum through which bile flows.

CANAL OF SCHLEMN
Location: Mammalian eye
Function : It lies near the junction ofcornea and sclera, this canal passes circularly around the cornea, and drains the aqueous humour

CENTRAL CANAL (CEREBROSPINAL CANAL)
Location: Spinal cord
Function : It is situated in the centre of gray matter and extends entire length of the cord. Cerbrospinal fluid flows in it.

CERVICAL CANAL
Location: Uterus
Function : Canal of cervix of uterus

COCHLEAR CANAL (SCALA MEDIA)
Location: Internal ear of mammals
Function : It is middle canal in the cochlear duct filled with peri lymph

COLLETING DUCT
Location: Kidney of mammals
Function : These are many and collect urine.

CYSTIC DUCT
Location: part of bile duct in vertebrates,
Function :  which leads from gall bladder receives branches from various part of the liver and it eventually forms the common bile duct.

DUCT OF RIVINUS
Location: Salivary glands of mammals
Function : Ducts of sublingual glands (Sublingual ducts) lie just beneath the floor of the mouth and open into the floor qf the mouth.

ENDOLYMPHATIC DUCT
Location: Internal ear of mammals
Function : It is a small short duct connected with saccule and end blindly in the endo lymphatic sac.

EUSTACHWN TUBE (AUDITORY TUBE)
Location: Middle ear of all land vertebrates
Function : It connects middle ear with pharynx.

HAVERSIAN CANALS
Location: Bones
Function : These are longitudinal canals found characteristically in long bones.

HEPATIC DUCT
Location: Liver of vertebrates
Function : It originates from liver cells and unites with the cystic duct from the gall bladder to form the common bile duct.

HYALOID CANAL
Location: Eye of mammals
Function : It extends between optic disc and the lens.

INGUINAL CANAL
Location: Reproductive organs of male mammal.

Function : It connects abdominal cavity to scrotal cavity.

LACRIMAL DUCTS
Location: Eyes of man
Function : These are two (superior and inferior) connect lacrimal gland with lacrimal sac.

LACTIFEROUS DUCTS
Location: Mammary glands of placentals
Function : These carry milk from mammary glands to the tip of

LAURER’S CANAL(LAURER STIEDA CANAL)
Location: Reproductive organs of liver fluke
Function : It is temporary copulatory canal which opens on the dorsal body surface.

LYMPHATIC DUCT RIGHT
Location: Thorax of vertebrates
Function : It is a short duct receives lymph from the right side of the head, the right upper extremity and the right side of the thorax.

MANDIBULAR CANAL
Location: Lower jaw of mammals
Function : It originates from mandibular foramen for in- ferior alveolar vessels and nerve and lies on the inner surface of each ramus.

NASOLACRIMAL DUCT
Location: Nose
Function : It connects lacrimal sac with inferior nasal meatus.

NEURENTERIC CANAL
Location: Vertebrate embryo
Function : It is a canal joining the primitive gut with the cavity of neural tube.

PANCREATIC DUCT (DUCT OF WIRSUNG)
Location: Pancreas
Function : The duct which conducts enzymes from the pancreas into the duodenum.

PAPILLARY DUCT (DUCT OF BELLINI)
Location: Kidney of mammals (part of renal tubule)
Function : These open on the tip of renal papilla and pour their contents into a minor calyx of the renal pelvis.

PAROTID DUCT (STENSON’S DUCT)
Location: Salivary gland of mammals
Function : It passes anteriorly to pour into the yes- tibule of the mouth, opposite the upper second molar tooth.

SEMICIRCULAR DUCTS (CANALS)
Location: Internal ear of vertebrates
Function : These are filled with endolymph and concerned with equilibrium.

SUBMAXILLARY DUCT(WHARTON’S DUCT)
Location: Salivary gland of mammals
Function : It extends from the anterior end of each submaxillary gland and opens into the floor of the mouth on each side of the frenulum.

THORACIC DUCT
Location: Thorax and Abdomen of mammals
Function : The chief collecting duct of lymphatic system receive lymph from lacteals. It lead towards left subclavian

THYROGLOSSAL DUCT
Location: On the floor of pharynx in mammals
Function : An embryonic duct between thyroid and pharynx. it disappears in adults.

VERTEBRATERIAL CANALS
Location: Cervical vertebrae of mammals, birds and reptiles
Function : These canals are found at the base of transverse processes of cervical vertebrae for the passage of cervical blood vessels and nerves.

VOLKMANN’S CANAL
Location: Long bones of mammals
Function : These are transverse canals, connecting Haversian canals. These carry blood.