|Biology: 4. The Skeleton and Movement
Please remember to photocopy 4 pages onto one sheet by going A3→A4 and using back to back on the photocopier
OB24 Identify the main parts of the human skeleton and understand that the functions are support, movement and protection
OB25 Locate the major bones in the human body including the skull, ribs, vertebrae, collarbone, shoulder blade, humerus, radius, ulna, pelvis, femur, tibia and fibula, using a diagram or a model skeleton
OB26 Understand the function of joints and muscles (including antagonistic pairs), tendons and ligaments, and the relationship between these and bones
OB27 Describe the general structure and action of different types of joints: fused, ball and socket and hinged, and identify examples of each: skull, shoulder, elbow, hip, knee
The functions of the skeleton are support, protection and movement
Our skeleton supports our body and maintains its shape.
It also protects our soft organs; the skull protects the brain, the backbone protects the spinal cord, the ribcage protects heart and lungs etc.
Our skeleton also enables us to move with the help of muscles.
Muscles and Joints
The function of muscles and joints is to allow movement
Bones are moved by contraction of muscles.
Antagonistic pairs of muscles
Usually another muscle is used to return a bone to its original position. For this reason, muscles normally occur in pairs that exert opposite forces called antagonistic pairs.
Antagonistic muscles are pairs of muscles that pull in opposite directions to control the movement of a joint e.g. biceps and triceps.
A joint is the place where two bones move against each other.
Types of joints
Fused has no movement e.g. skull
Ball and Socket allows movements in all directions, e.g. hips, shoulder
Hinge can bend in one direction only, e.g. knee, elbow
Tendons and Ligaments
A tendon joins a muscle to a bone (it has little elasticity and cannot be stretched)
A ligament joins bone to bone (it is elastic and can be stretched)
There Must Be Love Before Babies
Tendons: Muscles to Bone, Ligaments: Bone to Bone
Synovial fluid lubricates the joint and allows the bones to move easily (it acts as a shock absorber).
Cartilage is soft skeletal tissue which covers and protects the ends of bones (it also acts as a shock absorber).
Test yourself – can you identify each of the following bones?