Answer: parasitism
Explanation: Because it's relationship between two species of plants or animals in which one benefits at the expense of the other, sometimes without killing the host organism.
The force of gravity affects all objects on Earth by pulling them towards the centre. The Earth is close to spherical in shape as this is the geometry gravity prefers. Without gravity, objects would be floating in space. The atmosphere would not exist as the air particles would have no force pulling them towards the planet. Gravity means when you throw something up, most of the time it will come down. It is a force, which causes objects to accelerate when they fall.
B connective; bind and support the body
