Trachea synthetic windpipes; however, a successful method for this method of transplant does not currently exist and development of such a method remains theoretically daunting. The word "trachea" is used to define a very different organ in invertebrates than in vertebrates. Insects have an open respiratory system made up of spiracles, tracheae, and tracheoles to transport metabolic gases to and from tissues. An adult's trachea has an inner diameter of about and a length of about 10 to 11 centimetres (4 in.). It begins at the bottom of the larynx, and ends at the carina, the point where the trachea branches
Composition of the human body are averages of different numbers reported by different references. The adult human body averages ~53% water. This varies substantially by age, sex, and adiposity. In a large sample of adults of all ages and both sexes, the figure for water fraction by weight was found to be 48 ±6% for females and 58 ±8% water for males. Water is ~11% hydrogen by mass but ~67% hydrogen by atomic percent, and these numbers along with the complementary % numbers for oxygen in water, are the largest contributors to overall mass and atomic composition figures. Because of water content, the human body