The Human Skeleton

Question 1

Functions of the Human Skeleton

Answer 1

Support
Protection
Locomotion (allows movement as muscles are attached to bones and cross joints)
Mineral reseves (calcium and phosphate stored, can be released depending on blood levels)
Haematopoiesis (blood cells produced within bone marrow)

Question 2

5 different shapes of bone, describe each and give an example

Answer 2

1. Long bones: longer than wide, long diaphysis/ shaft. E.g bones of the limb (femur)
2. Short bones: same width as length, similar to long bones. E.g. bones of wrists and ankles
3. Flat bones: thin, flat and usually curved. E.g. skull, sternum, scapula, ribs
4. Irregular bone: don’t fit into other catagories. E.g. vertebrae, sacrum, facial bones
5. Sesamoid bones: small, round bones embedded in tendons, protect tendon and increase movement. E.g. patella

Question 3

How is the skeleton organised?

Answer 3

Axial skeleton: including skull, vertebral column, ribs and sternum
Appedicular skeleton: pectoral girdle, bones of arms/ hads, pelvic girdle, bones of legs/ feet

Question 4

The skull: how many bones, function, 2 subgroups.
Check you can lable an image

Answer 4

22 bones total
Function: houses brain and special sense organs - protective function
Subgroups: Viscerocranium (facial skeleton - 14), Neurocranium (surrounding brain - 8)

Question 5

What are the 5 sections of the vertebral column? How many bones are in each? Features of each section?

Answer 5

Cerivcal (7) - small & relatively mobile, dislocation
Thoracic (12) - articulate with ribs, long processes for muscle attachment
Lumbar (5) - largest body, susceptible to herniated IVDs
Sacrum (5) - vertebrae fused, articulates with hip bones
Coccyx (4?) - fused, tailbone

Question 6

What are the two girdles? What bones are in each? What are their function?

Answer 6

Pectoral girdle:
- Clavical and scapula
- Clavical connects upper limb to axial skeleton
- Facilitates movement
Pelvic Girdle:
- Innominates (unamed), Ilium, ischium and pubis fused together
- Provides stability and protects pelvic organs

Question 7

What are the bones of the Upper Arm? How many of each?

Answer 7

Arm = Humerus
Forearm = Radius (lateral) and Ulna (medial)
Wrist = Carpals (8)
Hand = Metacarpals (5), Phalanges (14)

Question 8

What are the bones of the lower limb? How many of each?

Answer 8

Thigh = Femur
Leg = Tibia (medial) and Fibula (lateral)
Ankle = Tarsals (7)
Foot = metatarsals (5) and phalanges (14)

Question 9

What are the bone markings (7)? Breifly describe each

Answer 9

• Condyle/ epicondyle: rounded, knuckle-lke articular surface
• Crest/ line: ridge of bone
• Facet: smooth flat area, usually covered with cartilage, where bone articules with another bone
• Foramen/ notch: passage through bone/ indentation in bone
• Fossa: hollow or depressed area
• Process/ protuberance/ spine: extention or projection
• Trochanter/ tubercle/ tuberosity: elevation of the bone

Question 10

Sternum and ribs: function

Answer 10

• Surrounds and protects thoracic organs (thoracic cage)
• Important role in respiration
• Flexibility provided by costal cartilages

Question 11

What is the sternal angle? What is its importance?

Answer 11

An important anatomical landmark located where the 2nd ribs articulate anteriorly at the level of T4/5 IVD posteriorly. Forms boundry of mediastinum.
Allows us to palpate and locate 2nd ribs which can then count ribs from. Horizontal plane at level of sternal angle passes through several important structure.
Counting ribs useful in auscultation (listening for heart sounds)