Musculo-skeletal System

Question 1

Bones function

Answer 1

Support

Protection

Movement

Storage

• lipids
• minerals

Haematopoiesis

Question 2

Muscles

Answer 2

Movement

Maintenance of posture

Heat generation

Stabilise joints

Question 3

Feral skull - fonatanells

Answer 3

Anterior fontanelle- diamond shaped 2.5 cm wide 3cm long
Closes at 18 mounts

Posterior fontanelle- triangular shaped. Close at 6 weeks postnatal

Question 4

Joints of the body

Answer 4

Articulations

Sites where 2 or more bones meet

Hold skeleton together

Give skeleton mobility

Question 5

Composition of bone

Answer 5

Organic 35%
Osteogenesis cells
Osteoblasts- form bone
Osteoclasts- reabsorb bone

Osteocytes
Mature bone cells derived from osteoblasts

Osteoid
A mixture of proteins and carbohydrates material made by osteoblasts

Osteoid
A mixture of proteins and carbohydrate material made by osteoblasts

Inorganic (65%
Compounds containing calcium, gives bone it’s hardness

Question 6

Functional characteristics of muscle

Answer 6

Excitability

Contractility

Extensibility

Elasticity

Question 7

Chemical composition of muscle

Answer 7

75% water

20% proteins

Myosin
Actin
Tropmoyosin
Troponin
Myoglobin

5% other substances

Question 8

Three types of muscle

Answer 8

Cardiac

Smooth (involuntary)

Striated (voluntary of skeletal)

Question 9

Muscle contraction

Answer 9

Requires ATP and Ca++

Interaction between myosin (head) and actin

Myosin heads pivot which pull the actin filaments toward the centre of the sarcomere

Breaking the cross bridge requires energy

Regulated by Ca++ binds to tropnin tropmyosin is moves myosin heads can then attach to actin.