| A | B |
|---|
| ball-and-socket joint | A joint that allows movement in almost all directions |
| calcium | One of several minerals found in bones that can be obtained from dairy products |
| cardiac muscle | The muscle that makes up the heart, is involuntary, and has striations |
| cartilage | A tough, flexible tissue found wherever two or more bones come together; cushions and prevents bones from rubbing together |
| cell | The smallest unit in which all of the life processes can be carried on |
| connective tissue | Tissue that joins and supports different parts of the body |
| cramp | A painful and involuntary contraction of a muscle |
| cranium | The helmet-shaped part of the skull that encloses and protects the brain |
| dermis | The thicker, inner layer of skin |
| epidermis | The tough outer layer of the skin |
| epithelial tissue | Tissue made up of sheets of cells that cover and protect the inner and outer surfaces of the body |
| fixed joint | A joint that does not allow movement of the bones |
| fracture | A crack or break in a bone |
| gliding joint | A joint that allows sliding movements |
| hair follicles | Deep pockets in the dermis from which hair grows |
| Haversian canals | Pipelike passageways or channels in the bone that allow blood vessels to run through the bone |
| hinge joint | A joint that allows movement in only one direction |
| involuntary muscle | A muscle that is not under conscious control |
| joint | A place where two or more bones come together in the skeleton |
| keratin | A fibrous protein that waterproofs the skin and is also found in hair and nails |
| ligaments | Strong bands of connective tissue that hold two or more bones together at joints |
| marrow | A soft tissue inside bone containing blood vessels and living blood-forming cells |
| movable joint | A joint that allows full movement of bones |
| muscle tissue | Tissue made of muscle cells that can contract, or become shorter |
| muscular system | An organ system made up of all the muscles in the body; it produces movement of body parts |
| nerve tissue | Long, branched cells that carry messages throughout the body |
| organ | A group of two or more different tissues that work together and perform a certain function |
| organ system | A group of organs that work together and perform one or more specific functions |
| partially movable joint | A joint that only allows a small amount of movement in bones |
| pelvis | A bowl-shaped bone at the hips that helps to support the weight of the body |
| phosphorus | One of several minerals essential to bones |
| pivot joint | A joint that allows rotating movement from side to side |
| pores | Openings in the skin that allow moisture to evaporate |
| red marrow | Tissue in the bone that forms red blood cells; children up to 5 years of age only have this type |
| ribs | 12 pairs of curved bones attached to the spinal column that protect the heart and lungs |
| skeletal muscle | A muscle that is attached to and that moves the skeleton; are voluntary and has striations |
| skeletal system | An organ system made up of bones, joints, and connective tissue that help to support, move, and protect the body |
| skeleton | The structural framework that supports the body and protects the internal organs |
| smooth muscle | The muscle that makes up the walls of many organs inside the body; is also involuntary |
| spinal column | A series of small bones that enclose and protect the spinal cord |
| spongy bone | Area of bone that contains many air spaces |
| sprain | An injury that occurs when a ligament is stretched or torn away from a joint |
| sternum | A narrow, flat bone that helps stabilize the ribs and protect inner organs |
| sweat glands | Coiled tubes in the dermis that open to the outside of skin to give off moisture to help cool the body |
| tendon | Tough bands of connective tissue that attach skeletal muscles to bones |
| tissue | A group of cells that are similar in structure and function |
| vertebrae | 33 small ring-shaped bones that make up the backbone |
| voluntary muscles | A muscle that is under conscious control |
| yellow marrow | Tissue found in the bone that stores fat, but can produce blood cells after severe blood loss |
