Best Answer: In humans there are two. Glycogen, which is a long chain carbohydrate made by polymerising glucose molecules together, is stored in the liver and, in small amounts, in the muscles. It provides a fast boost of energy for short intense exercise.
A freshman is 9th grade - 14 - 15 yrs. old. A junior is in the 11th year of school./ A senior is in the 12th and final year of high school. Ages vary but a junior is 16-17 years old and a senior is 17-18 years old. Junior is 11 grade, senior is 12 grade (for high school) A junior would be around 17 and a senior around 18.
People in the United States who are more than sixty years of age are commonly referred to as senior citizens or seniors. These terms refer to people whose stage in life is generally called old age, though there is no precise way to identify the final stage of a normal life span.