This tube is the cartilaginous tube spoken of above and is known as the cartilaginous sheath of the notochord. The Works of Francis Maitland Balfour, Volume III (of 4) Francis Maitland Balfour. This structure is called the notochord (a string down the back).
GM diet stands for General Motors Diet, a 7-day weight loss programme based on an exclusive diet plan. This diet has a strict set of eating instructions for each day of the programme. But being a fast-paced weight loss diet, the diet is also known for its side-effects.
It's a Cyclical Ketogenic Diet, or CKD for short. CKD basically means that you cycle periods of low carb, high protein, and high fat with periods of high carb, high protein, and low fat. The majority of time you will be consuming a low carb diet, with a period set aside each week for carbing-up.