(1) Bones and the human skeleton

What are the functions of our skeleton?

The skeleton diagram does fill the screen, but you can't appreciate details if its size is reduced

In the diagram details of the bones of the hands and the feet are not shown.

Bones are made of tough calcium based materials and softer tissue.

The out layers of bone is made from strong and had tissues based on calcium compound molecules.

This makes bones strong and rigid - they don't bend easily.

The inner layers of bone are made from more softer spongy tissue, but still a fairly strong material.

The skeletal system as a whole has five main functions.

 

 

Five functions of bones

1. Protection

The bones are hard and protect the soft tissue of the organs of the body. e.g. the skull protects the brain, the ribs protect the lungs and heart, the backbone spinal cord that protects the nerve cells of the central nervous system that connects with the brain - this is why spine injuries are potentially very serious and harmful.

 

2. Support

The skeleton provides a strong framework on which the rest of the body 'hangs'. All the soft tissues of the larger important organs are supported by the skeleton allowing us to stand up without the organs falling down!.

 

3. Movement

Muscles are attached to bones (details in the next section), so the bones act as an anchorage for the various muscles systems of the body associated with movement.

The action of muscles allows the skeleton to move when joints allow movement of two or more bones in a bending actions.

We could not move unless e.g. elbow or knee joints can bend in two directions raising or lowering actions.

 

4. Production of blood cells

Certain of the longer and larger bones e.g. the humerus and femur, contain a soft tissue called bone marrow in the middle of them.

Bone marrow produces red blood cells, essential for transporting oxygen to cells using the haemoglobin molecule.

See Respiration - aerobic and anaerobic in plants and animals, investigations

Bone marrow also produces white blood cells that help fight harmful infections that enter your body.

 

5. Storage of essential materials

The bones are a good storage place for essential minerals such as calcium ions and phosphate compounds.

---

See Keeping healthy - communicable diseases

and Keeping healthy - non-communicable diseases

---

Key points -

Based on the syllabus-specifications for students taking the AQA, Edexcel and OCR GCSE level biology examinations (~US grades 9-10 biology).

---

Human Skeleton System – Biology Revision Notes

The human skeleton is a strong, internal framework made up of 206 bones in adults. It supports the body, protects vital organs, enables movement, and more.

---

Functions of the Human Skeleton

1. Support:

   • Forms the structural framework of the body

   • Holds the body upright and gives shape

2. Protection:

   • Skull protects the brain

   • Rib cage protects the heart and lungs

   • Vertebrae protect the spinal cord

   • Pelvis protects the reproductive organs

3. Movement:

   • Bones act as levers and joints act as pivots

   • Muscles are attached to bones via tendons and contract to move the skeleton

4. Making Blood Cells (Haematopoiesis):

   • Bone marrow (in long bones like femur and flat bones like the pelvis) produces red blood cells, white blood cells, and platelets

5. Storage of Minerals:

   • Bones store important minerals such as calcium and phosphorus, which can be released into the bloodstream when needed

---

Types of Bones

1. Long bones – e.g., femur, humerus

2. Short bones – e.g., carpals in the wrist

3. Flat bones – e.g., skull, sternum

4. Irregular bones – e.g., vertebrae

5. Sesamoid bones – e.g., patella (kneecap)

---

Main Parts of the Skeleton

• Skull: Encases and protects the brain

• Vertebral Column (Spine):

  • Made of 33 vertebrae

  • Divided into cervical, thoracic, lumbar, sacral, and coccygeal regions

  • Allows flexibility and protects the spinal cord

• Rib Cage:

  • 12 pairs of ribs

  • Connect to the sternum and protect internal organs

• Limbs:

  • Upper limbs: humerus, radius, ulna, carpals, metacarpals, phalanges

  • Lower limbs: femur, tibia, fibula, tarsals, metatarsals, phalanges

• Pelvis: Supports body weight, protects internal organs, anchors lower limb muscles

---

Joints and Movement (Brief Overview)

• Fixed Joints (Immovable): e.g., skull sutures

• Slightly Movable Joints: e.g., between vertebrae

• Synovial (Freely Movable) Joints:

  • E.g., knee, elbow, shoulder

  • Contain synovial fluid for lubrication

  • Allow wide range of movement

---

Summary Table

---

Keywords, phrases and learning objectives for this part on bones, muscles, skeleton and teeth

Be able to describe the structure function of different sets of skeleton bones e.g. those for protection, support, movement, production of red blood cells and storage of essential minerals.

Know the production of blood cells in bone marrow is important.

Know what bones and associated muscles are made of.

---

WHAT NEXT?

TOP OF PAGE

INDEX of biology notes on the skeleton and muscles

INDEX of all my BIOLOGY NOTES

This is a BIG website, so try using the [SEARCH BOX], it maybe quicker than the many indexes!

email doc brown - comments - query?

Basic Science Quizzes for UK KS3 science students aged ~12-14, ~US grades 6-8

Biology * Chemistry * Physics for UK GCSE level students aged ~14-16, ~US grades 9-10

Advanced Level Chemistry for pre-university age ~16-18 ~US grades 11-12, K12 Honors

Find your GCSE/IGCSE science course for more help links to all science revision notes

---

Explaining importance of structure & function of the human skeleton in GCSE level biology, What you need to know about structure & function of the human skeleton for GCSE level biology, Explaining use of structure & function of the human skeleton knowledge in GCSE level biology, Examples of structure & function of the human skeleton explained when studying GCSE level biology, What is the significance of structure & function of the human skeleton in GCSE level biology, describing explaining theory of structure & function of the human skeleton when studying GCSE level biology, exam revision notes for structure & function of the human skeleton, online help for understanding structure & function of the human skeleton in GCSE biology, what do I need to learn about structure & function of the human skeleton? what do I need to know about structure & function of the human skeleton for GCSE biology exams, how to prepare for questions on structure & function of the human skeleton in GCSE biology examination? structure & function of the human skeleton for syllabus-specifications for students taking the IGCSE/GCSE level biology examinations, summary revision notes key points on structure & function of the human skeleton for students studying AQA igcse/gcse biology notes on structure & function of the human skeleton, Edexcel gcse biology notes on structure & function of the human skeleton,  OCR 21st century GCSE biology notes on structure & function of the human skeleton, OCR gateway GCSE biology notes on structure & function of the human skeleton, WJEC gcse biology notes on structure & function of the human skeleton, CCEA gcse biology notes on structure & function of the human skeleton, CIE Cambridge igcse biology, notes on structure & function of the human skeleton useful for US grade 9-10 biology student courses

---