The Skeletal system

Question 1

What is the meaning of articulate in relation to bones?

Answer 1

Having a relationship with other bones.

Question 2

What is special about the hyoid bone?

Answer 2

This is the only bone that doesn’t articulate with other bones.

Question 3

Features of hyaline cartilage?

Answer 3

-most abundant
-support and flexibility
-covers ends of bones, connects ribs to sternum, supports nose.
-costal cartilage important for breathing as it allows the ribcage to be flexible.

Question 4

Features of fibrocartilage?

Answer 4

-strong and compressible
-in knees and discs between vertebrae and pubis
-shock absorber

Question 5

What are the parts of the axial skeleton?

Answer 5

The cranium, spine and ribcage.

Question 6

What are the parts of the appendicular skeleton?

Answer 6

The arms, upper and lower limbs.

Question 7

Why is support a function of bone?

Answer 7

Support against gravity and for the body and soft organs.

Question 8

Why is protection a function of bone?

Answer 8

For the brain, spinal cord and vital organs so they don’t get damaged.

Question 9

Why is movement a function of bone?

Answer 9

They act as levers for muscle action (mechanical advantage) and allow us to walk, talk etc.

Question 10

Why is mineral storage a function of bone?

Answer 10

Mineral such as calcium phosphate- makes bones strong and important for muscle function.

Question 11

Why is hormone storage a function of bone?

Answer 11

Growth factors are stored and released by osteoclasts (trigger the rebuilding of bone).

Question 12

Why is blood cell formation (haematopoiesis) a function of bone?

Answer 12

This is associated with the skeleton and is in the marrow.

Question 13

Why is triglyceride (fat) storage in bone cavities a function of bone?

Question 14

What are sesamoid bones?

Answer 14

These are embedded in tendon (patella and pisiform)- sort of look like sesame seeds.

Question 14

What are the 4 bone shapes?

Answer 14

Long, short, flat and irregular.

Question 15

Why are the ‘lumps’ on bone important (for example on the femur)?

Answer 15

These improve the actions of muscle and give more strength.

Question 16

Features of compact bone?

Answer 16

This type of bone is dense and has great strength.

Question 17

Features of spongy bone?

Answer 17

Look sort of like honeycomb, resistant to strains, have trabeculae and can redesign to help absorb/ account for different stresses on the bone.

Question 18

What is trabeculae?

Answer 18

Looks like honeycomb, interlocking plates of bone and contains red bone marrow where blood cells are produced.

Question 19

What is the diaphysis?

Answer 19

This middle part of bone (straight).

Question 20

What is the epiphysis?

Answer 20

The rounded ends of bone (proximal and distal).

Question 21

What is the epiphyseal line?

Answer 21

This is a line of cartilage to help the bone grow in length and as the bone starts calcifying, the area remains as cartilage.
When you stop growing, this area calcifies (more permanent).

Question 22

What is the periosteum?

Answer 22

This is the outer layer of the bone and contains 2 layers (fibrous- collagen and osteogenic- rich in cells and blood vessels)

Question 23

What are sharpey’s fibres?

Answer 23

These are fibres that are needed to attach the periosteum to the bone.

Question 24

What is the endosteum?

Answer 24

This is the internal layer that lines cavities and canals.

Question 25

Function of osteoclasts in maintaining bone thickness?

Answer 25

They remove the inner part of the bone as the outer part grows to maintain a suitable thickness.

Question 26

In an osteon, why do the collagen fibres run in different directions with each lamellae?

Answer 26

This offers resilience to twisting and bending forces.

Question 27

What is the function of lamellae?

Answer 27

These are the concentric cylinders of compact bone and these give long bones rigidity and restraint (impact resistant).

Question 28

What is the structure of spongy bone?

Answer 28

The structure is more freestyle than compact bone
-no osteons
-irregularly arranged lamellae
-osteocytes interconnected by canaliculi

Question 29

What are the main features of a synovial joint?

Answer 29

-nerve and blood supply
-articular cartilage- very smooth and slick
-inner synovial membrane
-outer fibrous layer that is tough (lots of collagen)
-joint cavity containing synovial fluid (lubricant, slick)

Question 30

What are the 6 types of synovial joint?

Answer 30

-ball and socket (head of humorous)
-hinge (ulna)
-saddle (metacarpal)
-pivot (radio ulna)
-gliding (inter carpal)
-condyloid (metacarpophalangeal)

Question 31

What is a bursae?

Answer 31

Between areas of friction (muscle and bone), they develop synovial pouches with fluid which allows structures to move against each other without grinding.

Question 32

What are fat pads?

Answer 32

These are protective (adipose tissue) and are in many synovial joints.

Question 33

What are ligaments?

Answer 33

These hold bones together and are dense connective tissue to help stop dislocation.

Question 34

What are menisci?

Answer 34

These are c- shaped cartilage that are in the knee (fibrocartilage so shock absorber).

Question 35

What are tendon sheaths?

Answer 35

These allow tendons to smoothly move against each other and are made up in a similar way to bursae (shaped like hot dog buns).

Question 36

What are lacunae?

Answer 36

These are small gaps (cavities) in bone that hold the osteocytes.

Question 37

What does hyaline cartilage look like?

Answer 37

The lacunae are very spaced out (containing chondrocytes) and lots of ground substance (can’t see any fibres).

Question 38

What does elastic cartilage look like?

Answer 38

Lacunae are closer together and lots of elastic fibres seen.

Question 39

What does fibrocartilage look like?

Answer 39

This looks like dense connective tissue with many collagen fibres and chondrocytes are few and far between.