Free Biological Importance of Water MCQs with Answers

• A. 15 to 16
• B. 16 to 18
• C. 15 to 20
• D. 25 to 29

Explanation: The specific heat capacity is defined as the quantity of heat (J) absorbed per unit mass (kg) of the material when its temperature…

• A. Universal solvent
• B. Polar nature
• C. Hydrogen bonding
• D. Becomes denser when it freezes.

Explanation: The statement in option (d) is false and not a property of water. Water actually becomes less dense when it freezes.

• A. Heat of vapourization
• B. Specific heat capacity
• C. Heat of ionization
• D. Polarity of water

Explanation: The heat of vaporization is the amount of heat energy required to convert a unit mass of a substance (in this case, water) from its liquid…

• A. Tension.
• B. Cohesion.
• C. Adhesion.
• D. Ambibition.

Explanation: Cohesion: Hydrogen bonds make water sticky. Water has an amazing ability to adhere (stick) to itself and to other substances.

• A. High specific heat capacity
• B. Hydrogen bonding
• C. Cohesion and tension
• D. Hydrophobic exclusion

Explanation: Hydrophobic exclusion cause water molecules to be repelled by the hydrophobic tails of phospholipids, causing them to cluster around the…

• A. A
• B. B
• C. C
• D. None of these

Explanation: Option A is the hypertonic solution, as it causes the cells to shrink due to the movement of water out of the cell towards the higher…

• A. Isotonic
• B. Hypotonic
• C. Hypertonic
• D. Hyposmotic
• E. Hyperosmotic

Explanation: The human body maintains an isotonic environment, which means that the concentration of solutes is equal inside and outside of the cells.

• A. Muscle cells
• B. Bone cells
• C. Brain cells
• D. None of the above

Explanation: The correct answer is brain cells. Brain cells, or neurons, have a high water content of approximately 85%, which is vital for their role…

• A. Heat of neutralization of water
• B. Heat of condensation of water
• C. Heat of vaporization of water
• D. Specific heat of water

Explanation: The specific heat of water is a measure of the amount of heat energy needed to raise the temperature of one gram of water by 1°C.

• A. With the release of large amount of water, a small amount of heat loss can take place.
• B. With the release of small amount of water vapours, a great amount of heat loss can take place.
• C. It will keep their temperature very high.
• D. No cooling effect, with the release of even a large amount of water vapours.

Explanation: As per the formula Q=mL, since water has a high latent heat of vaporization (L), for a small mass or amount of water (m), a large amount…

• A. Solute particles from higher concentration to lower concentration
• B. Solvent particles from higher water potential to lower water potential
• C. Solute particles from higher concentration to lower concentration through a semipermeable membrane
• D. Solvent particles from lower water potential to higher water potential

Explanation: Osmosis is the movement of water molecules from an area of high water potential to an area of low water potential through a semi-permeable…

• A. 85%
• B. 95%
• C. 97%
• D. 73%

Explanation: The commonly quoted water content of the human brain is about 73%, reflecting the high water requirement of nervous tissue for metabolism…

• A. 1-2%
• B. 3-4%
• C. 5-7%
• D. 90%

Explanation: Cuticular transpiration is a small fraction of total transpiration, commonly given in this syllabus as about 5% to 7%, so 5% to 7% is the…

• A. Hypertonic
• B. Hypotonic
• C. Isotonic
• D. Heterotonic

Explanation: In isotonic conditions, water potential is the same as in cell sap, solute concentration is also the same as in cell sap.

• A. Less water leaves the cell than enters it, so the cell shrinks.
• B. More water enters the cell than leaves it, so the cell swells and bursts.
• C. Water enters the cells and none leaves it, so the cell swells and bursts.
• D. Water enters the cell and more leaves it, so the cell shrinks.

Explanation: b) More water enters the cell than leaves it, so the cell swells and bursts:This option is partially correct.

• A. Surface tension
• B. Polarity
• C. Heat capacity
• D. Viscosity

Explanation: Water is a good solvent because of its polarity and ability to form hydrogen bonds.

• A. 7.45 to 7.55
• B. 7.35 to 7.45
• C. 7.15 to 7.25
• D. 7.25 to 7.35

Explanation: Blood is normally slightly basic, with a normal pH range of about 7.35 to 7.45. Usually the body maintains the pH of blood close to 7.40.

• A. Solvent property
• B. Heat capacity
• C. Ionization
• D. Protection

Explanation: Water can absorb and retain heat, which helps stabilize the temperature in living organisms.

• A. Specific Heat Capacity
• B. Hydrogen Bonding
• C. Cohesion and Adhesion
• D. Hydrophobic exclusion

Explanation: If you place a few drops of oil on the surface of a water solution, the oil drops will tend to coalesce (to unite into one whole) into a…

• A. Heat of vaporization
• B. Hydrogen bonding
• C. High polarity
• D. Cohesion and adhesion

Explanation: Water is called the "universal solvent" because it dissolves more substances than any other liquid.