Instead, many of them attach under the skin. This allows you to contract your facial muscles just a tiny bit and make dozens of different kinds of faces.
Even the smallest movement can turn a smile into a frown. You can raise your eyebrow to look surprised or wiggle your nose. And while you're looking at your face, don't pass over your tongue — a muscle that's attached only at one end!
Your tongue is actually made of a group of muscles that work together to allow you to talk and help you chew food. Stick out your tongue and wiggle it around to see those muscles at work.
Because there are so many skeletal muscles in your body, we can't list them all here. But here are a few of the major ones:. Reviewed by: KidsHealth Medical Experts. Larger text size Large text size Regular text size. Smooth Muscles Smooth muscles — sometimes also called involuntary muscles — are usually in sheets, or layers, with one layer of muscle behind the other. Page 1 A Hearty Muscle The muscle that makes up the heart is called cardiac muscle. Skeletal Muscle. Face Muscles You may not think of it as a muscular body part, but your face has plenty of muscles.
Major Muscles Because there are so many skeletal muscles in your body, we can't list them all here. But here are a few of the major ones: In each of your shoulders is a deltoid say: DEL-toyd muscle. Your deltoid muscles help you move your shoulders every which way — from swinging a softball bat to shrugging your shoulders when you're not sure of an answer. Muscles work in pairs and sometimes in more than pairs 2 because it makes the movement smooth.
The muscle that is making the move is called the prime mover while another is called the antagonist and it resists the move. It slowly "lets go". This way the movement is not jerky. There are often other muscles involved, especially if the joint is complex like the shoulder joint or the knee joint.
There are also helpers of the prime mover which are called on when more force is needed. Nervous system. Brain Sex Sleep. If you can see the Flash movie then please ignore this message.
Muscle pairs: Muscles are grouped together in pairs on your skeleton Relaxed or contracted: When one muscle of a pair contracts, the other relaxes. Human body homepage The body homepage Interactive body Muscles game Facts and features Muscle anatomy diagram - front view Muscle anatomy diagram - back view Muscles and Exercise Facial Muscles Fast and slow twitch muscles Structure and contraction Muscle tone Skeletal, smooth and cardiac muscle Psychology tests Disgust Spot the fake smiles Memory test.
Muscle function test The BBC is not responsible for the content of external websites. The ribs form a cage that shelters the heart and lungs , and the pelvis helps protect the bladder, part of the intestines, and in women, the reproductive organs. Bones are made up of a framework of a protein called collagen , with a mineral called calcium phosphate that makes the framework hard and strong.
Bones store calcium and release some into the bloodstream when it's needed by other parts of the body. The amounts of certain vitamins and minerals that you eat, especially vitamin D and calcium , directly affect how much calcium is stored in the bones. In this soft bone is where most of the body's blood cells are made.
The bone marrow contains stem cells, which produce the body's red blood cells and platelets, and some types of white blood cells. Red blood cells carry oxygen to the body's tissues, and platelets help with blood clotting when someone has a cut or wound. White blood cells help the body fight infection. Bones are fastened to other bones by long, fibrous straps called ligaments pronounced: LIG-uh-mentz. Cartilage pronounced: KAR-tul-ij , a flexible, rubbery substance in our joints, supports bones and protects them where they rub against each other.
The bones of kids and young teens are smaller than those of adults and contain "growing zones" called growth plates.
These plates consist of multiplying cartilage cells that grow in length, and then change into hard, mineralized bone. These growth plates are easy to spot on an X-ray. Because girls mature at an earlier age than boys, their growth plates change into hard bone at an earlier age. Bone-building continues throughout life, as a body constantly renews and reshapes the bones' living tissue.
Bone contains three types of cells:. Muscles pull on the joints, allowing us to move. They also help the body do such things as chewing food and then moving it through the digestive system. Even when we sit perfectly still, muscles throughout the body are constantly moving. Muscles help the heart beat, the chest rise and fall during breathing, and blood vessels regulate the pressure and flow of blood.
When we smile and talk, muscles help us communicate, and when we exercise, they help us stay physically fit and healthy.
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