Four functions of the skeleton
Four functions, each needing the exact phrase. Shape and support: holds the body upright and bears its weight. Muscle attachment for movement: a muscle contracts and pulls on the bone, which acts as a rigid lever at a joint. Protection of vital organs: cranium/brain, ribs/heart and lungs, pelvis/lower organs. Production of red blood cells: by red bone marrow inside bones such as the pelvis and femur. A one-word answer like movement is not credited.
Named bones by body region
0413 requires the location and the function of a fixed list of named bones. Head: cranium (protects the brain). Shoulder girdle: clavicle and scapula. Arm and hand: humerus, radius and ulna, then carpals, metacarpals and phalanges. Trunk: ribs (protect heart and lungs) and pelvis (hip girdle). Leg and foot: femur, patella, tibia and fibula, then talus, tarsals, metatarsals and phalanges. Give both the location and the function -- the full table is in the note.
Bone classification: long, short, flat
0413 uses only three classes. Long bones have a long shaft with rounded ends (femur, humerus, tibia, phalanges) and act as levers for movement. Short bones are small, cube-shaped and clustered (carpals; tarsals including the talus), for compact movement and shock absorption. Flat bones are thin, broad plates (cranium, scapula, ribs, pelvis) with a wide surface for muscle attachment and protection. The patella is not one of the three -- it just protects the knee.
Drawn from real examiner reports.
Patella has no long/short/flat class
The patella (kneecap) is not classified as a long, short or flat bone at 0413, so do not force it into one of the three. Its role is simply to protect the front of the knee joint. Candidates sometimes call it long, because it sits among the leg bones, or flat, because it looks plate-like -- both wrong. If asked, give its protective function, not a class.
Naming a bone is not classifying it
Naming a bone (the cranium) and classifying it (a flat bone) are separate skills the mark scheme credits separately, so give both when asked. Candidates often name the bone and stop -- examiners flagged the sternum being missed as a flat bone. Fix: once you have named a bone, add its class, checked against the shape definition rather than guessed from size or familiarity.
Digest (### 1.1): candidates often named a bone correctly but skipped its classification, specifically missing that the sternum is a flat bone (s22 P12 Q1b; s22 P11 Q7b(i)).
Vague function wording scores zero
Function answers need the exact mechanism, not a one-word label. Movement alone scores nothing -- the credited phrase is provides muscle attachment for movement, because attaching muscle to bone is what lets movement happen. Likewise protects the brain beats a bare protection. Give the specific mechanism, not the generic noun.
Digest (### 1.1): function answers need the specific mechanism, not a one-word answer -- movement alone is too vague, the credited version is provides muscle attachment for movement (s22 P12 Q1c; w22 P11 Q1a; w23 P11 Q14a).
Function not applied to a sport
A correct function still loses marks when the question names an activity and the answer stays generic. Examiners repeatedly see functions stated with no link to the sport or performer in the stem. Fix: after the function and its mechanism, tie it to a specific action -- e.g. the pelvis protects a footballer's lower organs in a heavy tackle.
Digest (### 1.1): functions are often stated generically without being linked to the required named activity (s22 P12 Q1c; w22 P11 Q1a; w23 P11 Q14a).
Carpals (wrist) vs metacarpals (palm)
The prefix meta- marks the bones one step out from the named group: carpals are the wrist but metacarpals the palm, and tarsals the ankle but metatarsals the sole. Candidates asked for the wrist bones often write metacarpals, and mix up tarsals and metatarsals the same way. Fix: plain name = the joint, meta- name = the palm or foot beyond it.
Classify flat bones by shape, not looks
Flat bones are not always obviously flat -- the cranium is domed, the ribs curve and the pelvis is chunky -- so candidates misclassify them on first impression. The test is thin, broad and plate-like with a wide protective surface, which cranium, scapula, ribs and pelvis all meet. Check each bone against the shape definition, not its size or how familiar it is.
The skeleton does not create movement
Shortening muscle attachment for movement to just movement hides a real error: bones cannot move themselves. A bone is a rigid lever; a muscle attached across a joint contracts and pulls on it, rotating it. Without a bone to pull against there is no movement. The chain is: muscle contracts, pulls on the bone, the bone moves as a lever. The skeleton does not move on its own.
Digest (### 1.1): movement alone is too vague, the credited function is provides muscle attachment for movement, and the causal link (muscle pulls on bone) is the part candidates most often drop (s22 P12 Q1c; w22 P11 Q1a).
Run name, classify, function, apply
These questions reward a chain, not one fact. Read the command word: name wants the bone; classify wants long/short/flat with a shape reason; function wants the exact phrase; apply links it to a named activity. Marks are capped when only one is given -- run all four.
Match answer length to the command word
Give what the command word demands and no more. State and identify want a brief, precise answer and are often over-written; explain and describe want a developed reason and are often left at bare description. Check the command word and the marks before writing.
Do not repeat the question stem
Information already in the question earns no marks if you just repeat it. If the stem says a bone protects an organ, restating that is not credited -- add your own knowledge: name the bone, give its class, or state the mechanism. Go beyond the stem every time.
Four functions -- precise wording matters.
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