cover one eye and you will your lose depth perception. so, with two eyes you can judge the distance of an object but only within a metre or so because of the relative position of the eyes to the object yeeeaaah.
visual cliff
Depth is the distance of measuring something from it's top to bottom. Such as how deep a swimming pool is.
depth (an extent downward or backward or inward)
It varies. You would think it should be about 24-25" (which is a standard counter depth) but in reality many are closer to 27".
Tissues usually have more than one layer of cells. Normally you can see two to three cell thicknesses which is why this is important.