1. Blood is distributed to various parts of the body through blood vessels known as _______.   Hint First letter clue   2. Salivary glands secrete a fluid known as _______ which helps in digestion as well as in swallowing of food.   First letter clue   3. An average human adult has _______ teeth.   First letter clue   4. Complex food particles are broken into simple food particles through the process of _______.   First letter clue   5. _______ is a tubular structure through which urine is excreted out of the body.   First letter clue   6. _______ are the organs of hearing.   First letter clue   7. _______ is a sac-like structure which stores urine.   First letter clue