L5 - Skeletal System

Question 1

What are the classes of bones?

Answer 1

Flat bones, irregular bones, long bones, short bones.

Question 2

What is the process of bone formation called?

Answer 2

Ossification.

Question 3

What does the skeletal system consist of?

Answer 3

Bones (skeleton), joints, cartilages, ligaments.

Question 4

What type of tissue is bone/osseous tissue?

Answer 4

Supporting connective tissue.

Question 5

What are the main components of bone matrix?

Answer 5

Extracellular protein fibres and ground substance.

Question 6

What fraction of bone weight is calcium phosphate?

Answer 6

About 2/3.

Question 7

What fraction of bone weight is collagen fibres?

Answer 7

About 1/3.

Question 8

What percentage of bone mass is made up of osteocytes and other cells?

Answer 8

2%.

Question 9

What are the five main functions of bones?

Answer 9

Support, protection, storage of minerals and fats, blood cell production, movement.

Question 10

How do bones provide support?

Answer 10

They offer structural support for the whole body, framework for attachment of organs and soft tissues, and attachment sites for muscles.

Question 11

How do bones function in storage?

Answer 11

They store minerals (calcium, phosphorus) and fats (yellow bone marrow stores adipose tissue).

Question 12

Where is most of the body’s calcium stored?

Answer 12

In bones as calcium salts.

Question 13

How is calcium deposition and removal from bones controlled?

Answer 13

By hormones, to maintain homeostasis.

Question 14

Where does blood cell production (haematopoiesis) occur?

Answer 14

In red bone marrow.

Question 15

What types of blood cells are produced in bone marrow?

Answer 15

Red blood cells (erythrocytes), white blood cells, platelets.

Question 16

How do bones facilitate movement?

Answer 16

They provide surfaces for muscle, ligament, and tendon attachment and act as levers when stimulated.

Question 17

How many bones are in the adult skeleton?

Answer 17

206.

Question 18

What are the two main subdivisions of the skeleton?

Answer 18

Axial skeleton and appendicular skeleton.

Question 19

What does the axial skeleton include?

Answer 19

Facial and cranial bones, vertebrae, ribs, sternum (80 bones).

Question 20

What does the appendicular skeleton include?

Answer 20

Upper and lower limbs, anchored to the axial skeleton (126 bones).

Question 21

What are the two main types of bone tissue?

Answer 21

Compact bone and spongy bone.

Question 22

What are the characteristics of compact bone?

Answer 22

Dense, smooth, and homogeneous.

Question 23

What are the characteristics of spongy bone?

Answer 23

Meshwork of uneven spaces.

Question 24

What are the four groups of bones based on shape?

Answer 24

Flat bones, irregular bones, long bones, short bones.

Question 25

What are examples of flat bones?

Answer 25

Ribs, sternum, bones of the skull.

Question 26

What are examples of irregular bones?

Answer 26

Vertebrae, facial bones.

Question 27

What are examples of long bones?

Answer 27

Femur (leg), humerus (arm).

Question 28

What are examples of short bones?

Answer 28

Carpals (wrist), tarsals (ankle).

Question 29

What is the structure of a long bone?

Answer 29

Central shaft (diaphysis) surrounding marrow/medullary cavity, made of compact bone, surrounded by periosteum, expanded ends (epiphyses) covered by articular cartilage.

Question 30

What does the periosteum do?

Answer 30

Covers outside of bones, provides a route for nerves and blood vessels, isolates bone from surrounding tissues, important for bone growth and repair.

Question 31

What attaches skeletal muscle to bone?

Answer 31

Tendons.

Question 32

What attaches bone to bone?

Answer 32

Ligaments.

Question 33

What is the endosteum?

Answer 33

A membrane that covers spongy bone of marrow cavity and inner surfaces, active during bone repair, remodelling, and growth.

Question 34

What are the three main types of cells in bone?

Answer 34

Osteoblasts, osteocytes, osteoclasts.

Question 35

What is the function of osteoblasts?

Answer 35

Produce new bone matrix (ossification), promote deposition of calcium salts in the organic matrix.

Question 36

What happens when an osteoblast is surrounded by calcified matrix?

Answer 36

It differentiates into an osteocyte.

Question 37

What is the function of osteocytes?

Answer 37

Maintain bone matrix, repair and recycle calcium salts in bony matrix.

Question 38

What is the function of osteoclasts?

Answer 38

Break down bone matrix (osteolysis/resorption), secrete enzymes and acids to release stored minerals, regulate phosphate and calcium concentration in body fluids.

Question 39

What is a closed/simple fracture?

Answer 39

An internal fracture seen only on x-rays.

Question 40

What is an open/compound fracture?

Answer 40

A fracture that projects through the skin, more dangerous due to infection/bleeding risk.

Question 41

What is a communicated fracture?

Answer 41

Several breaks result in many small pieces between two large segments.

Question 42

What is an impacted fracture?

Answer 42

One fragment is driven into the other, usually as a result of compression.

Question 43

What is a transverse fracture?

Answer 43

Breakage of bone shaft along its long axis.

Question 44

What is an oblique fracture?

Answer 44

Breakage occurs at an angle that isn’t 90 degrees.

Question 45

What is a displaced fracture?

Answer 45

Produces new abnormal bone arrangement.

Question 46

What is a non-displaced fracture?

Answer 46

Retains the normal alignment of bones.

Question 47

What is a compression fracture?

Answer 47

Occurs in vertebrae when subjected to extreme stress, often associated with osteoporosis.

Question 48

What is a spiral fracture?

Answer 48

Produced by twisting stresses that spread the length of the bone.

Question 49

What is the first step in fracture repair?

Answer 49

Formation of a fracture hematoma (6-8 hours after injury).

Question 50

What is a fracture hematoma?

Answer 50

A large blood clot that forms after a fracture, stopping bleeding and forming a fibrous meshwork.

Question 51

What happens after a fracture hematoma forms?

Answer 51

Lack of blood flow leads to osteocyte death and area of dead bone along bone shaft.

Question 52

What is the second step in fracture repair?

Answer 52

Callus formation (48 hours after injury).

Question 53

What forms the internal callus?

Answer 53

A network of spongy bone that unites inner edges of fracture.

Question 54

What forms the external callus?

Answer 54

Cartilage and bone that encircle and stabilize outer edges of fracture.

Question 55

What is the third step in fracture repair?

Answer 55

Spongy bone formation-osteoblasts replace central cartilage with spongy bone, uniting broken ends.

Question 56

What is the fourth step in fracture repair?

Answer 56

Compact bone formation and remodelling.

Question 57

Name nutrients important for bone tissue.

Answer 57

Vitamin D, calcium, vitamin K, fluoride, magnesium, omega 3 fatty acids.

Question 58

What is the role of vitamin D in bone tissue?

Answer 58

Needed for calcium absorption.

Question 59

What is the role of calcium in bone tissue?

Answer 59

Required to make calcium phosphate and calcium carbonate, which form hydroxyapatite crystals for bone hardness.

Question 60

What is the role of vitamin K in bone tissue?

Answer 60

Supports bone mineralization, has a synergistic effect with vitamin D.

Question 61

What is the role of fluoride and magnesium in bone tissue?

Answer 61

Structural components of bone tissue.

Question 62

What is the role of omega 3 fatty acids in bone tissue?

Answer 62

Reduces inflammation, which may interfere with function of osteoblasts.

Question 63

What is calcium required for in the body?

Answer 63

Bone mineralisation, heart rate regulation & contraction, health of teeth, coagulation of blood, nerve impulse conduction, contraction of skeletal and smooth muscles.

Question 64

What is hypocalcemia?

Answer 64

Low levels of calcium.

Question 65

What is hypercalcemia?

Answer 65

High levels of calcium.