8th Grade Health Term Exercise - Chapter 1 Match each term in the middle to the correct definition.         nucleus cerebrum organs striated insertion origin voluntary muscles skeletal muscles cytoplasm isometrics chromatin endocrine system membrane tendon motor nerves tissues organelles protoplasm cerebellum muscle tone cardiac involuntary muscles systems steroids metabolism       1. groups of similar cells form ___________. 14. the part of the brain which controls the skeletal muscles             2. control center for all of the functions that take place in the cell 15. muscles over which you have no conscious control             3. a loosely coiled, threadlike material in the nucleus 16. ___________ join the skeletal muscles to the bone             4. living material which makes up the cell 17. The part of your brain which directs the process of  thinking             5. organs group together to form __________. 18. the part of the muscle that is anchored to a relatively immovable part (like a bone) is called the _____             6. thick fluid inside of the cell membrane 19. nerves which the brain sends messages to when you need to move a muscle             7. similar tissues group together to form ___________. 20. ____________ muscle tissue is found only in the heart.             8. The cell ________ surrounds and protects the other parts of the cell. 21. constant slight contraction of the muscle fibers             9. tiny organisms that move through the cytoplasm and perform chemical reactions and functions 22. exercise in which one set of muscles is tensed for several seconds in opposition to another set of muscles or to an immovable object             10. The point where the muscle is attached to the bone. It is always pulled toward the origin. 23. the part of your body designed to regulate growth             11. muscles that you can consciously control 24. the process by which your body produces and uses energy from food             12. the main purpose of this is to contract causing the bones to move 25. synthetic growth hormones             13. skeletal muscles are also known as ________ muscles.