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.
Bones and Muscles Your bones and muscles have to work together in order for you to move. Most of the bodyâs bones are associated with muscles. Muscles can only contact or shorten.They pull on bones in order to move. Muscles work in pairs to move your bones.se the model to answer the following questions. GENTLY pull on the muscles to determine how the muscles and bones work together to make the body move. Do not touch the bones (wooden pieces). You may hold onto the base. Pull only on the fishing line or the metal rings. Do not pull on the labels.