A large variety of marine invertebrates and fish live at great depths in the ocean where the pressure could be less than 100 times the normal atmospheric pressure that we experience. How do they under such crushing pressure and do they have any special enzymes ?

What kind of adaptation is seen in a large variety of marine invertebrates and fish that live great depths in the ocean?

Torricelli was the first do devise an experiment for measuring atmospheric pressure . He took calibrated hard glass tube , 1 m in lengt and of uniform cross section , closed at one end . He filled the whole tube with dry mercury taking care than no air or water droplets remain inside the tube , closed the opposite end of the tube tightly with thumb and inverted it . He put this inverted mercury tube into a mercury through , taking care that the end of the tube remains inside the mercury through , An interesting thing was noticed . Mercury in the tube fell down at first and then stopped at a particular position . The height was 76 cm above the free surface of mercury in the through . When the given tube was inclined or lowered in the mercury trough , the vertical haight of mercury level in the tube was always found constant . Torricelli explained this by saying that the free surface of mercury in the trough . Hence , the hydrostatic pressure exerted by the trough measures the atmospheric pressure . If this expriment uses water instead of mercury , then A. length of water will be equal to 76 cm B. length of water will be less than 76 cm C. length of water will be greater than 76 cm D. none of the above

Torricelli was the first do devise an experiment for measuring atmospheric pressure . He took calibrated hard glass tube , 1 m in lengt and of uniform cross section , closed at one end . He filled the whole tube with dry mercury taking care than no air or water droplets remain inside the tube , closed the opposite end of the tube tightly with thumb and inverted it . He put this inverted mercury tube into a mercury through , taking care that the end of the tube remains inside the mercury through , An interesting thing was noticed . Mercury in the tube fell down at first and then stopped at a particular position . The height was 76 cm above the free surface of mercury in the through . When the given tube was inclined or lowered in the mercury trough , the vertical haight of mercury level in the tube was always found constant . Torricelli explained this by saying that the free surface of mercury in the trough . Hence , the hydrostatic pressure exerted by the trough measures the atmospheric pressure . If an additional hole is also made at P ' at the top point of the tube , then A. mercury will not come out of the tube B. mercury may come out of the tube after some time . C. mercury will come out of the tube instantly D. none of these