Grave's disease was originally described by an Irish physician, Dr. Robert Graves, in 1835.

Development of oesophagus begins at 3rd week of gestation. Fetus takes the first swallow by 14th week.

Esophagus is 25cm long extends from C6 to T12.

The external sphinter of urinary bladder consists of striated muscles innervated by perineal branch of pudendal nerve -S2,S3.