skeleton

Question 1

bone structure

Answer 1

• bone is not smooth and exhibits multiple markings such as bulges which serve as sites for attachment for muscles, ligaments and tendons
• projections are sites of muscle and ligament attachment
• bone exhibits depressions and openings

Question 2

the axial skelton 1 - the skull

Answer 2

• 8 cranial bones that enclose the brain and provide attachment for head and neck muscles
• 14 facial bones which form the framework of the face and cavities for special sense organs; provide openings for air and food passage and sites of attachment for teeth
• most bones are flat apart from the mandible

Question 3

hyoid bone

Answer 3

• considered part of the skull despite not actually being connected to the skull
• lies in anterior neck just inferior to the mandible
• doesnt articulate with any other bone
• acts as a moveable base for the tongue

Question 4

the axial skeleton 2 - vertebral column

Answer 4

• extends form the skull to the pelvis and transmits the weight of our trunk to our lower limbs
• surrounds and protects the delicate spinal cord and provides attachment points for ribs and muscles of back/neck
• flexible, curved structure consisting of 26 irregular bones
• 7 cervical (C1-C7) - neck
• 12 Thoracic (T1-T12) - thoracic cage
• 5 Lumbar (L1-L5) - LOWER BACK
• 5 sacral (S1-S5) - bone inferior to the lumbar vertebrae
• 3-4 coccyx - terminus of vertebral column

Question 5

vertebral column

Answer 5

• not a straight column, curvatures increase the resilience and flexibility of spine
• cervical and lumbar regions are concave, thoracic and sacral are convex
• abnormal spine curvatures=
• scolliosis - abnormal lateral curve
• kyphosis - hunchback
• lordosis - swayback
• bones are supported by discs (cushion-like pads of gel) and ligaments

Question 6

axial skeleton 3 - thoracic cage

Answer 6

• composed of thoracic vertebrae, sternum, ribs (12 pairs) and their cartilage
  FUNCTIONS
• protects vital organs of thoracic activity
• supports shoulder girdle and upper limbs
• ## provides attachment sites for many muscles

Question 7

the appendicular skeleton

Answer 7

• bones of the limbs and their girldes
• appendid to the axial skeleton
• enable us to carry out typical movements

Question 8

pectoral (shoulder) girdle

Answer 8

• consists of the clavical anteriorly and the scapula posteriorly
• attaches the upper limbs to the axial skeleton and provides attachment points for muscles that move in upper limbs

Question 9

the upper limb

Answer 9

• 30 bones form the framework
• the arm (brachium) consists of the humerus
• the forearm (Antebrachium) consists of the radius and ulna
• hand (manus) has 8 carpal bones (wrist), 5 metacarpal bones (palm) and 14 phalanges (fingers)

Question 10

pelvic girdle

Answer 10

• formed by the sacrum and 2 hip bones (coxal bones)
• attaches the lower limbs to the axial skeleton with strong ligaments, transmits the wright of upper body to lower limbs and supports pelvic organs
• hip bones consist of 3 fused bones=
• ilium (forms superior region of hip-joins with sacrum)
• Ischium (forms inferior part of hip-sit bones)
• pubis (forms the anterior part of hip-joined in the midline by the pubic symphysis)

Question 11

lower limb

Answer 11

• carries entire weight of the erect body and is subjected to exceptional forces when we jump or run
• thigh (femur) is the largest/strongest bone in the body
• leg (tibia, fibula)
• Foot (Pedal) composed of 7 tarsal bones (ankle) 5 metatarsal bones and 14 phalanges in the toes

Question 12

the skeleton as a foetus

Answer 12

• skull has more bones than adult skull (mandible and frontal bones are unfused0
• thoracic and sacral curvatures are obvious at birth giving the spine its C shape, cervical and lumbar curves appear as we develop

Question 13

the skeleton at birth

Answer 13

• cranium is huge relative to the face
• at 9 months old, cranium is 1/2 adult size
• mandible and maxilla are foreshortened
• arms/legs grow at faster rate than head/trunk
• epiphyseal growth plates in long bones fuse at the end of adolescence
• bones are still subject to modelling

Question 14

the skeleton as we age

Answer 14

• intervertebral discs become think, less hydrated and less elastic
• loss of stature by several cm is common by 55
• risk of disc herniation increases
• “dowagers hump” - kyphosis
• costal cartilages ossify, causing thorax to become rigid
• all bones lose mass

Question 15

major bones in the body

Answer 15

• Skull – and mandible
• Spine – cervical, thoracic and lumbar vertebrae, sacrum and coccyx
• Chest – ribs and breastbone (sternum)
• Arms – shoulder blade (scapula), collar bone (clavicle), humerus, radius and ulna
• Hands – wrist bones (carpals), metacarpals and phalanges
• Pelvis – hip bones
• Legs – thigh bone (femur), kneecap (patella), shin bone (tibia) and fibula
• Feet – tarsals, metatarsals and phalanges.