The short answer is yes. The reason you don't feel it underwater is because of buoyancy. The longer (but by no means exhaustive!) answer: Gravity varies very VERY slightly on different place on the Earth (due to differences in the density of the Earth, etc.), but the relative strength of the gravitational force between your body and the Earth does not change in any significant way, whether you are on top of a mountain or far underwater. (If you had a spacecraft, the force would weaken as you travelled further from the Earth.) The gravitational force between two objects is dependent on their masses and their proximity, which is why we can only see gravity in action when at least one of the objects is very large (like the Earth). Since your mass does not change when you're underwater and the Earth's mass does not change (and since the change in your position relative to the Earth -- on top of a mountian or at the bottom of the ocean -- is insignificant), the gravitational force does not change significantly. Mind you, there would be relatively small FELT changes if you were to travel to the bottom of the ocean (the Mariana Trench for example), mostly because a percentage of the Earth's mass would be pulling you AWAY from the center of the Earth. In this case, though, the actual force being exerted on your body would be the same as on the surface -- only the felt effect of gravity would be reduced. Everything on this earth feels the effects of gravity, even fish. Fish don't sink in the water, because their density is nearly the density of water, so the force of gravity is counteracted by buoyancy. But they still have mass, and so they are still subject to the force of gravity. Same with you and me. As a side note: Strictly speaking, weight (when considered a function of force, not only mass) is properly measured using a unit called a newton. Isaac Newton's law of universal gravitation (in English, for the curious): The force of gravity between two objects (F) equals the mass of one object multiplied by the mass of the second object multiplied by the Gravitational constant (G, equal to 6.67 x 10^-11 Newton meters ^2/kg^2), all divided by the square of the distance between the two objects. (This means that gravity is strongest between two very large objects, and gets weaker as these objects get further apart.) Hope this helps a bit.

Yes but due to the upthrust of water objects can be lifted easily.

Water is a thicker medium so objects fall slower than they would in air, though gravity is the same. As would a parachute that captures more of the medium that it descends through, slowing it down. Without any obstruction all objects would fall at the same rate, as in a vacuum.