Question

give reason muscles can contact and relax to cause movement​

Answer 1

ᴍᴜsᴄʟᴇs ᴀʀᴇ sᴘᴇᴄɪᴀʟ ғɪʙʀᴇs ɪɴ ᴛʜᴇ ʙᴏᴅʏ ᴛʜᴀᴛ ᴄᴏɴᴛʀᴀᴄᴛ ᴀɴᴅ ʀᴇʟᴀx ᴛᴏ ᴄᴀᴜsᴇ ᴍᴏᴠᴇᴍᴇɴᴛs. ᴍᴏᴠᴇᴍᴇɴᴛ ɪs ᴄᴀᴜsᴇᴅ ʙʏ ᴛʜᴇ ᴄᴏɴᴛʀᴀᴄᴛɪᴏɴ ᴀɴᴅ ʀᴇʟᴀxᴀᴛɪᴏɴ ᴏғ ᴍᴜsᴄʟᴇs. ᴡʜᴇɴ ᴏɴᴇ ᴍᴜsᴄʟᴇ ᴄᴏɴᴛʀᴀᴄᴛs, ᴛʜᴇ ᴏᴛʜᴇʀ ʀᴇʟᴀxᴇs ᴀɴᴅ ᴛʜɪs ᴄᴀᴜsᴇs ᴅɪsᴘʟᴀᴄᴇᴍᴇɴᴛ. ᴛʜᴇ ᴍᴜsᴄʟᴇs ᴏғ ᴏᴜʀ ʜᴇᴀʀᴛ ᴀʀᴇ ᴄᴀʟʟᴇᴅ ɪɴᴠᴏʟᴜɴᴛᴀʀʏ ᴍᴜsᴄʟᴇs ᴀs ᴛʜᴇʏ ᴅᴏɴ'ᴛ ᴡᴏʀᴋ ᴀᴄᴄᴏʀᴅɪɴɢ ᴛᴏ ᴏᴜʀ ᴡɪʟʟ.

Answer 2

Answer:

Muscles are special fibres in the body that contract and relax to cause movements. Movement is caused by the contraction and relaxation of muscles. When one muscle contracts, the other relaxes and this causes displacement. The muscles of our heart are called involuntary muscles as they don't work according to our will.