Bones And Joints

Question 1

Which bones are part of the axial skeleton?

Answer 1

The skull
The spine
The sternum
The ribs

Question 2

Which bones belong to the appendicular skeleton?

Answer 2

pectoral girdles (Schultergürtel)
pelvic girdle (Hüftgelenk)
upper limbs
lower limbs

Question 3

Which functions has the skeleton?

Answer 3

The skeleton’s functions are

1. movement, provided by moveable long bones that acts as levers. Muscles attach via tenons and where they contact pull on the levers to create movement.
2. storage for mineral salts such as calcium and magnesium phosphate which are essential for bone growth and health. Bones owe it’s hardness (compression/strength) to these mineral deposits. A lack can lead to weak bones (osteoporosis).
3. Protection of the internal structures and vital organs.
4. Shape/structure. There are three main body shapes/types or somatotypes.
5. Production of red and white blood cells in the bone marrow of certain bones.

Question 4

Which 3 somatotypes are there?

Answer 4

1. Ectomorph - typically Talk and thin with narrow shoulders, hips and chest.

2.
endomorph - rounded appearance, with wide hips and narrow shoulders

3. mesomorph - muscular physique, with wide shoulders and narrow hips.

Question 5

Which function have the red blood cells?

Answer 5

They contain haemoglobin, which facilitates gaseous exchange, the exchange of oxygen and carbon dioxide.

Question 6

Which function have the white blood cells?

Answer 6

They are dedicated to defend the body against infection, disease and foreign materials.

Question 7

Which are the gender differences of the skeleton?

Answer 7

Generally male bones tend to be heavier.
Commonly, females have a greater carrying angle at the elbow joint, a smaller femoral head at the hip joint and a wider pelvis to accommodate childbirth.

This alignment which is perfect for childbirth is not the best for performing exercise involving legs the wider hip joints makes the femurs slope inwards to compensate. This may cause the knees to roll inwards during some exercise. This angle between the hip joints and the knees is often referred to as the Q angle.
In contrast the narrower male pelvis allows more vertical femurs, which are more efficient for leg exercise.

Question 8

What are the main structures of the skeleton?

Answer 8

• pectoral girdle (shoulder)
• pelvic girdle (hip)
• Upper limbs
• lower limbs
• vertebral column/spine

Question 9

What is the pectoral girdle composed of?

Answer 9

It’s composed of a double set of two bones on the right and left sides of the body. The clavicles -slender doubly curved long bones that run horizontally across the upper chest and can be felt just below the neck.

Question 10

What do the clavicles articulate with?

Answer 10

With a sculpt in a gliding synovial joint at the shoulder. Also with the sternum in the chest to form a synovial saddle joint. The joint has a cartilaginous disc that absorbs considerable stress (e.g when falling on the shoulder). In fact, this joint is so strong that the clavicles itself is much more likely to break than the joint dislocate.

Question 11

What are the scapulae?

Answer 11

Rough triangular thin, flat bones that partially cover the ribs 2-7.

Question 12

What is the acromion process and what does it articulate with?

Answer 12

The acromion process is a large bony process in which the raised ridge along the length of the posterior surface of each scapula ends

Question 13

How is the knob on top of the shoulder called?

Answer 13

It is called the acromio clavicular joint (AC joint). Where the clavicle and the acromion process articulate.

Question 14

What gives the shoulder girdle and the associated upper their incredible mobility?

Answer 14

The many muscles of the back and shoulder joint that anchor the scapulae in place

Question 15

What does the diagram show?

Answer 15

It shows that there is a depression- the glenoid cavity - laterally at the top of the scapula. This forms the socket that the head of the humerus fits into, forming a synovial ball and socket joint.

Question 16

Why does the Latin translation of clavicle mean little key?

Answer 16

Coz the bone rotates along its axis like a key when the shoulder is abducted ( arm lifted out to the side). This is the most commonly broken bone

Question 17

Which are the Scapulae’s two unique motions?

Answer 17

The shoulder blades moves sideways around the ribs in the protraction and retraction movements and it rotates in the abduction and adduction movements.

Question 18

What is described as hitting the funny bone?

Answer 18

If the ulna nerve running downy the humerus bones is knocked.

Question 19

What is the radius named after?

Answer 19

After the round, disc like head that connects it to the humerus.

Question 20

What kind of motions does the rotating (pivoting) radius’ round head enable?

Answer 20

It enables the body to perform palm-up and palm-down motions without moving the elbow.

Try: hold your arms out in front with your palms down so that the ulna sits underneath the palm radius. The radius rotates to turn the hand over. The ulna only flexes and extends because it is a hinge joint.

Question 21

What makes human hands so flexible?

Answer 21

The little cluster of carpal bones lying between the wrist and the fingers

Question 22

What are the meta-carpals?

Answer 22

The finger bones after the carpals. (Tarsals and meta tarsals in toes)

Question 23

What are the small bones at the fingers called?

Answer 23

Phalanges

Question 24

The pelvic girdle has the same function as the pectoral girdle. However there is one difference. What is it and what is the consequence?

Answer 24

The pelvic girdle has to carry more weight and is bearing the lower limbs and must thus provide more stability. The trade-off to this stability is a reduced range of motion, particularly at the ball and socket hip joint.

Question 25

What is the most significant gender difference between the skeletons?

Answer 25

As the females hip is designed for childbirth the hole in the middle of the pelvic bones is slightly wider and the gap filled by cartilage of the pubis symphysis is also bigger.