security threat meaning, security threat definition | English Cobuild dictionary. security. 1 n-uncount Security refers to all the measures that are taken to protect a place, or to ensure that only people with permission enter it or leave it.
A muscle expands when it relaxes. The muscles in our bodies are attached to bones. They help the bones move, much like strings help a puppet move. But muscles can pull in only one direction. They cannot push.Each bone is usually attached to a pair of muscles.ones and muscles work like  ropes and levers. The muscles can only pull against the bone not  push it. So to bend your arm at the elbow, the â¦ bicep pulls the  lower arm up. To streighten your arm, the tricep pulls the lower  arm back out. the muscles have to work in pairs opposite each other  to make movement.
Well first of all the bones are connected to muscles with tendons and the muscles move bones by working in pairs. The muscle pairs pull each other to move the bones. One muscl â¦ e contracts while the other muscle relaxes, to move the bone again the other muscle contracts and the other one relaxes.our muscles have the task of pulling your ligaments and joints so you can move your body limbs and organs, the muscles and bones work together by pulling on each other and supporting each other to move body parts.