Man does not live by food alone. Water is vital to human health and fitness. Although it is not a nutrient per se as are carbohydrates, fats, proteins, vitamins and minerals. It, in fact, is a key nutrient as no life is possible without it. Whereas we can do for weeks without food, we cannot live without water longer than a couple of days. Water approximates 60 per cent of the body weight of human adults. The total amount of water in a man weighing 70 kilograms is approximately a little over 40 liters. It is an excellent solvent—more substances are soluble in water than in any other liquid known so far. This makes it an ideal constituent of the body fluids which sustain life supporting chemical reactions. It dissolves varied products of digestion and transports them to the rest of the body. Likewise, it dissolves diverse metabolic wastes and helps drain them out of the body. Besides, it performs a variety of functions— some well-known and well understood while others not so well appreciated yet vital. The no less important role of water is to distribute/dissipate the body heat efficiently, thereby regulating body’s temperature. Water accomplishes this role ideally because it has high thermal conductivity ensuring rapid heat transfer from one part to the other.
Above all, water has a high-specific heat, implying that it takes a lot of heat to raise the temperature of water and likewise much heat must be lost to lower its temperature.
Drinking a lot of water is an inexpensive way to stay healthy. Even excess of water is harmless. Water therapy— drinking a liter or so the first thing in the morning is kidney-friendly.
The water regulation in the body is affected by hypothalamus in two ways i. e., (i) by creating the sensation of thirst which makes us drink water and (ii) by controlling the excretion of water as urine. If water regulation fails, medical emergency ensues.

On the basis of your understanding of the passage, answer the questions that follow.

Q1. Water is vital to human health and fitness because:
a) Man does not live by food alone
b) It is an excellent solvent
c) We cannot survive for more than a couple of days without it
d) It controls thirst and excretion of water as urine
Q2. Water is called a key nutrient because:
a) It dissolves different products of digestion
b) No life is possible without it
c) It carries products to the rest of the body
d) It raises temperature of the body
Q3. Water is an ideal constituent of the body fluids because:
a) It is an excellent solvent
b) It dissolves metabolic wastes
c) It drains wastes out of the body
d) It regulates excretion of urine
Q4. Water regulates body temperature efficiently as:
a) It circulates easily
b) It has high-specific heat
c) It dissolves food easily
d) It has high thermal conductivity
Q5. What does the author mean when he uses the word ‘regulation’ in the last para?
a) Official rule
b) Control
c) Device for fair use
d) Worn or used as per rules

Q6. Which component is an inexpensive way to stay healthy?
a) Water
b) Minerals
c) Vitamins
d) Proteins
Q7. Which of the following statements is not true?
a) A Water regulates body temperature
b) Excess water is not harmless
c) Excess water is not harmful
d) Water transports nutrients to the body
Q8. Which activity is considered as water therapy?
a) Its high thermal conductivity ensuring rapid heat transfer from one part to another
b) Drinking a liter of water in the morning
c) Drinking excess quantity of water
d) All of the above
Q9. What is the per cent of water content in a human body?
a) 60%
b) 40%
c) 80%
d) 70%
Q10 Which word in para 2 conveys the opposite of ‘similar’ ?
a) Dissipate
b) Ideal
c) Accomplished
d) Diverse