1. 3.1.1.1 – The structure and functions of the musculo-skeletal system
Learning objectives
To be able to describe the functions of the skeleton.
To be able to recognise and label a skeleton.
To understand the different joint classifications.
To be able to describe and analyse the different types of joint movements and how they are used during sporting movements.
To be able to label the voluntary muscles in our body
To explain the term ‘antagonist pair’ and provide examples

2. Bones
The adult skeleton has 206 bones and provides the framework for all movement.
Photo by: © istock Photo
Watch me
How many bone names do you know already?

3. Bone names Head/Neck joint Cranium Vertebral column
Photo by: © istock Photo

4. Bone names
Shoulder joint
Scapula
Humerus
Photo by: © istock Photo

5. Bone names
Chest region
Ribs
Sternum
Photo by: © istock Photo

6. Bone names
Elbow region
Humerus
Radius
Photo by: © istock Photo
Ulna

7. Bone names
Hip joint
Femur
Photo by: © istock Photo
Pelvis

8. Bone names
Femur
Patella
Knee joint
Photo by: © istock Photo
Tibia

9. Bone names
Fibula
Tibia
Photo by: © istock Photo
Talus
Ankle joint

10. Functions of the skeleton
The skeleton performs many functions in the body.
1. Support – The skeleton supports the muscles.
2. Protection – The skeleton protects delicate parts of the body like the brain.
3. Movement – Muscles are attached to the bones and once contracting allows movement.
4. Structural shape and points for muscle attachment – The skeleton gives us our shape/size and creates levers.
5. Mineral storage – vital minerals such as Calcium and Phosphorus are stored in bones.
6. Blood cell production – blood cells are made in the bone marrow.

11. 1. Support
It gives the body support, enabling us to stand. The bones of the body are held together by ligaments.
The skeleton provides a framework for the muscles, which are attached to bones by tendons.
Photo by: © istock Photo

12. 2. Protection
Some of our body parts, such as the brain, are very delicate and need protection.
Bones can protect body parts from impacts and injuries.
1. What vital organ does the Cranium protect?
Answer:
2. What vital organ does the Rib Cage protect?
Photo by: © deshow.net

13. 3. Movement
Muscles are firmly attached to bones forming levers to allow for sporting movements.
Photo by: © deshow.net

14. 4. Structural Shape & Muscle Attachment
The skeleton acts as a framework.
Muscles are firmly attached to bones forming levers to allow for sporting movements.
Photo by: © deshow.net

15. 5. Mineral Storage
The minerals in your bones serve two main functions. Minerals transform spongy bone matrix into a rigid structure and in turn increase density and strength.
Your bones also function as a mineral storage depot, releasing dissolved calcium, phosphorus and magnesium into your bloodstream if needed.
Photo by: © deshow.net

16. 6. Blood cell production
The ends of long bones and some other bones including the ribs, humerus, femur and even vertebrae bones, contain red bone marrow.
This is where the red blood cells are produced which carry oxygen.
Other functions include:
White blood cells to combat illness
Platelets for clotting and healing.
Storage of Calcium and Phosphorus
Photo by: © deshow.net

17. Structure of the skeleton
A joint is….
“A joint is a place where two or more bones meet”
The skeletal system has a number of joints which are responsible for the huge range of movement.
There are several different types of joint in the body which allow different types of movement.
Photo by: © istock Photo

18. Structure of the skeleton
Bones are divided into a number of different categories all with different roles in the body.
1. Long bones
Long bones have a long shaft and are responsible for a lot of movement and often act as levers. This is how sporting actions are created.
Photo by: © deshow.net / LOCOG
Long bones in the body include the femur, humerus, tibia, fibula, metatarsals, metacarpals and phalanges.

19. 1. Protection for delicate areas. i.e. the cranium protects the brain.
Structure of the skeleton
2. Flat bones
Flat bones perform a number of functions.
1. Protection for delicate areas. i.e. the cranium protects the brain.
2. Provides a broad surface area for muscle attachment. i.e. muscles in the back attach to the pelvis.
Photo by: © deshow.net

20. Structure of the skeleton
3. Short bones
Short bones are light, small and very strong. The primary function is to support the weight of the body.
The carpals in the wrist and the tarsals in the foot are examples of short bones.
Photo by: © deshow.net
How does this aid sportspeople in an event?
Gymnasts used these bones to support movements such as a handstand

21. Structure of the skeleton
4. Irregular bones
Irregular bones are specially shaped to perform a particular function.
These functions include:
Protection
Muscle attachment
Photo by: © deshow.net
Examples include the patella and the vertebrae.

22. Muscles of the body Watch me
Muscles are used in everyday life all the time. Sportspeople are reliant on the power of muscles to perform at the highest level.
Photo by: © paddynapper on Flickr. This image is reproduced under the terms of the Creative Commons License 2.0.
Photo by: © deshow.net
Watch me
What do you know about muscles already?

23. Muscles shorten when they contract and lengthen when they relax.
Voluntary Muscles
What happens when muscles contract?
Muscles shorten when they contract and lengthen when they relax.
Photos: © Stock.xchng.

24. Voluntary Muscles Rotator Cuffs Pectorals Triceps Deltoid
Latissimus Dorsi
Bicep
Abdominals
Gluteals
Hip Flexors
Hamstring
Quadriceps
Photo: © Stock.xchng.
Gastrocnemius
Tibialis Anterior

25. Structure of a synovial joint
Synovial joints are the most common type of joint in the body. These joints vary in structure for example, the shoulder is a ball-and-socket joint and the knee is a hinge joint. All synovial joints have the following structures.
Synovial membrane
Synovial fluid
Joint capsule
Cartilage
Ligament

26. Structure of a synovial joint
The following structures help prevent injury.
Cartilage prevents the ends of bones rubbing together at joints.
Synovial fluid – lubricates the joint allowing the parts to move freely.
Ligaments – these are tough, elastic fibres that link bones to bones.
Tendons – These connect muscles to bones.

27. Types of freely moveable joints
1. Ball and socket joint - the rounded end of a bone fits inside a cup-shaped end.
Ball and socket joints allow movement in all directions. These are the most mobile joints in the body.
Examples found in the body: Shoulders and hips.
Photo by: © deshow.net
Why are these joints important for sport?
Most sporting movements require the type of movement the shoulder and hip allow. i.e. tennis serve

28. Types of freely moveable joints
2. Hinge joints - only allow forwards and backwards movement like the hinge on a door.
Examples found in the body: The knee and elbow.
Photo by: © LOCOG
Why are these joints important for sport?
These joint are extremely powerful and in conjunction with surrounding muscles can produce power and speed i.e. Knee drive during a 100m sprint

29. Movement of a joint 1. Flexion and Extension
FLEXION – Decreasing the angle at a joint. (Bending the joint)
EXTENSION - Increasing the angle at a joint. (Straightening the joint)
Photo: © LOCOG
Photo: © toga on Flickr. This image is reproduced under the terms of the Creative Commons License 3.0.

30. Movement of a joint 2. Abduction and Adduction
Abduction and Adduction is determined from the ‘MIDLINE’ of the body.

31. Movement of a joint ADDUCTION –
Sideways moving limb towards midline of the body.
ABDUCTION –
Sideways moving limb away from midline of the body
REMEMBER: Adduction is to ADD towards the midline.
REMEMBER: Abduction is to TAKE AWAY from the midline.
Photo: © LOCOG

32. Movement of a joint 3. Rotation of the shoulder
The joint moves in a circular motion. e.g. Service action or bowling action.
Photo: © LOCOG
Photo: © ervine_wa on Flickr. This image is reproduced under the terms of the Creative Commons License

33. Movement of a joint 4. Planter-Flexion and Dorsi-Flexion
The action of pointing toes away from the body.
Dorsi-flexion –
The action of pulling toes towards the body.
Photo: © LOCOG
Photo: © ervine_wa on Flickr. This image is reproduced under the terms of the Creative Commons License

34. Apply it! What has stuck with you?
What movements occur during these action?
Photo: ©LOCOG

35. Cyclist Footballer Swimmer - Start Butterfly Stroke
FLEXION – at the RIGHT knee joint
EXTENSION - at the LEFT knee joint
FLEXION – at the RIGHT hip joint as the leg raises
FLEXION – Slight Flexion at the elbows
FLEXION – Torso (body is bent forwards)
EXTENSION – at the knee joints
FLEXION – at the HIP JOINT of right leg
ADDUCTION – at the hip joint as the left leg is moving towards the central line of the body
ADDUCTION – Left arm
FLEXION – at left elbow
Swimmer - Start
Butterfly Stroke
ADDUCTION – of the arms
EXTENSION – at the knee joints
EXTENSION – at the elbows
ROTATION – at the shoulder joint
EXTENSION – at elbow joints
ABDUCTION – of the arms

36. Antagonistic muscle action
At the elbow joint the agonist is the bicep muscle.
The tricep here is the antagonist
Photo: © Stock.xchng.
Muscles are arranged in antagonistic pairs.
As one muscle contracts (shortens) its partner relaxes (lengthens). E.g. Bicep and Tricep.

37. Antagonistic muscle action
Can you think of another antagonists pair in the body?
Photo: © adamkr on Flickr. This image is reproduced under the terms of the Creative Commons License

38. Antagonistic muscle action
Gastrocnemius and Tibialis Anterior acting at the ankle joint.
Hamstring and Quadricep acting at the knee joint.
Hip Flexors and Gluteals acting at the hip joint.
Photos: © adamkr on Flickr. This image is reproduced under the terms of the Creative Commons License

39. Apply it! Musculo-skeletal system What has stuck with you?
What are the 6 functions of the skeletal system?
Explain what is meant by an antagonistic pair and an example in the body?
Highlight on your body as many bones as possible.
Analyse the bones and major muscles working at the
a) Knee joint
b) Shoulder joint
Musculo-skeletal system

40. Practice it! Exam questions
1. Which bones are found at the shoulder joint? (1)
A Femur and tibia
B Humerus and radius
C Scapula and humerus
D Tibia and fibula
2. Which bones are found at the elbow joint? (1)

41. Practice it! Exam questions
3. The humerus is a long bone. Which of the following statements correctly identifies a function of the humerus and its associated advantage to the performer in the statement? (1)
A a hockey player can reach further to hit the ball as the humerus is a long bone
B a footballer can kick the ball harder due to the length of the humerus
C the humerus acts as a lever so a hockey player can apply more force to the ball
D the humerus protects the footballer from injury.

42. Practice it! Exam Questions:
4. Using an example from a sport of your choice, identify the two types of movement that can occur at a hinge joint. (4) 1. 2.
5. Figure 1 Shows a tennis player. The forehand action involves the use of many joints within the body.
a) Identify the type of synovial joint working at the
shoulder (1)

43. Practice it! Exam questions
6. Figure 4 shows a high board diver in flight.
Complete the following statements about the diver.
(i) The high diver has his legs at the knee and folded his body by at the
joint to allow him to bend forward (3)
(ii) The diver’s arms are at the elbow. The muscle that contracts to bring about this movement is the (2)

44. Practice it! A Exam questions B 7. Figure 5 is a diagram of a joint. C
i) What is the name and type of joint shown in Figure 5? (2)
Joint name
Joint type
(ii) Name the bones of the joint labelled A, B and C in Figure 5. (3) A B C B C

45. Practice it! Marks Scheme: C B Flexion & Extension
(Flexion) lifting a hockey stick in preparation to strike the ball (Extension) movement of the stick downwards to strike the ball
5. a) Ball and socket

46. Practice it! Marks Scheme:
6. i) Extended/extension, Flexing/flexion, Hip ii) Flexed, Bicep iii) Ball and Socket
7. i) Knee, Hinge ii) Femur, Patella, Tibia