Help Me Please?
Filed in Category Respiratory System Books
my brother is the third grade has a science test tomorow but didnt bring the book with him!!!! he has a study guide though. and there were 3 pages loong he did all of them except for these questions can u help us out?
1) In 3-5 sentences, explain how messages travel in our bodies.
(this was a lesson about the nervous system)
2)In 3-5 sentences, explain how the breathing model works. (respiratory system)
3)In 3-5 sentences, explain how the model arm works. (muscle system)
4) In 3-5 sentences, explain how the pumping blood works at rest and in periods of activity. (i think they mean the pulse of the heart this is about the circulatory system)
2 Comments so far
3) The muscles work together contracting and relaxing. When the biceps muscle (at the front attached to the radius bone) contracts, the triceps muscle (at the back attached to the ulna) relaxes causing the arm bend at the elbow. When the triceps muscle contracts and the biceps muscle relaxes the arm straightens. This is because when each muscle contracts, it is pulling on the bone as the other relaxes, releasing their pull.
3) The muscles work together contracting and relaxing. When the biceps muscle (at the front attached to the radius bone) contracts, the triceps muscle (at the back attached to the ulna) relaxes causing the arm bend at the elbow. When the triceps muscle contracts and the biceps muscle relaxes the arm straightens. This is because when each muscle contracts, it is pulling on the bone as the other relaxes, releasing their pull.
I revised this recently. You should try looking in Wikipedia for the other answers