Intro to musculoskeletal system

Question 1

What is diaphysis?

Answer 1

Middle section of a long bone

Question 2

What is epiphysis?

Answer 2

End sections of a long bone

Question 3

What is metaphysis?

Answer 3

Where the middle and the end of the long bone meet
- contains the growth plate (physis)

Question 4

What is the medullary cavity?

Answer 4

Contains bone marrow

Question 5

What is bone remodelling?

Answer 5

The continuous deposition and resorption of bone
- rate is influenced by hormones
- Forces like shear, tension and compression lead to remodeling

Question 6

Hormones affecting rate of bone remodelling

Answer 6

• PTH
• Calcitonin

Question 7

3x ways of classifying bones

Answer 7

• topologically; location
• formation/growth; endochondral or intramembranous
• shape; long/short, sesamoids

Question 8

LONG BONES

Answer 8

• two ends
• growth plates
• compact and spongy bone
• medullary cavity

Question 9

SHORT BONES

Answer 9

• as long as they are wide
• compact and spongy bone
• no medullary cavity

Question 10

FLAT BONES

Answer 10

• thin, wide flat
• compact bone that surrounds spongy

Question 11

SESAMOID BONES

Answer 11

• found in tendons and ligaments
• close to joints

Question 12

What is apophysis?

Answer 12

protrusion that develops from independent ossification centre
- attachment sites for tendons and ligaments
- called tuberosity

Question 13

What is a foramen?

Answer 13

• opening in the bone
• passages for nerves, blood vessels or muscles

Question 14

What is a fossa?

Answer 14

Cave or depression in the bone
- accommodates muscles & other structures

Question 15

Cranial bones

Answer 15

• composed of mostly paired bones
• ventral part of cranium, bones are endochondral
• dorsal part of cranium, bones are intramembranous
• many foramina for nerves and blood vessels

Question 16

Mandibular bones

Answer 16

• several foramina
• mandibular foramen; inferior nerves
• coronoid process; attaches temporalis
• angular process; attaches masseter
• masseteric and pterygoid fossae
• body and ramus (vertical)
• two mandibular bones joined at the symphysis

Question 17

Hyoid bones

Answer 17

• series of bony rods
• suspend the tongue and larynx
• stylohyoid visible in the guttural pouch of horse

Question 18

Types of vertebrae

Answer 18

• cervical; neck (7 in mammals)
• thoracic; articulate with ribs
• lumbar; lower back
• sacral; fused together and articulate with pelvis
• caudal; tail

Question 19

Between vertebrae

Answer 19

• intervertebral discs between vertebrae
• spinal nerves exit via intervertebral foramina

Question 20

Ribs

Answer 20

• paired
• dorsal part is bony ventral is cartilage
• articulate with sternum directly or to cartilage of above ribs
• cartilage of last rib may fail to connect; floating rib

Question 21

Sternum

Answer 21

• Most cranial element is called manubrium
• Xiphoid cartilage attaches to linea alba

Question 22

Pelvic limb

Answer 22

• pelvic girdle
• articulated with the sacrum dorsally
• 3x bones (ilium, pubis, ischium)
• fuse into one structure

Question 23

Leg bones

Answer 23

• Femur; offset femoral head for articulation in the acetabulum
• prominent trochanters for muscle attachments
• Patella; sesamoid bone in quadriceps tendon

Question 24

Birds skeleton differences

Answer 24

• modified thoracic limb; additional bone called the coracoid
• Fusion of many bones for strength and weight reduction
• Loss of teeth
• Pneumatised bones, air sacs in the medullary cavity
• Medullary cavity; important calcium reservoir to calcify egg shells

Question 25

Reptile skeleton

Answer 25

- less bone remodelling - elastic cartilage in skull, movement between bones - have coracoid - vertebrae (presacral, sacral and caudal) - epiphysis don't close

Question 26

Types of muscle

Answer 26

- smooth; involuntary - striated; voluntary - cardiac

Question 27

Striated muscle

Answer 27

- contains many fascicles enclosed in epimysium - fascicles consist of many muscle cells bound in perimysium - many mitochondria - many contractile myofilaments in interlocking arrangement

Question 28

What is the fascia?

Answer 28

- Collective term for the connective tissues - endomysium - perimysium -epimysium

Question 29

What are Sharpey fibres?

Answer 29

when muscles attach directly to bone collagen fibres continue as sharpey fibres

Question 30

Tendons

Answer 30

- collagen fibre bundles in a regular arrangement - primary, secondary and tertiary bundles - low metabolic needs

Question 31

Tendon sheaths and bursae

Answer 31

- sacs or tubes containing cavities filled with synovial fluid and with synovial lining - protect against pressure and friction

Question 32

Types of ligaments

Answer 32

- white ligaments; rich in collagen fibres - yellow ligaments; lots of elastic fibres

Question 33

Pennate Muscles

Answer 33

- fascicles insert at an angle to the central tendon - more fibres beside each other more force generated - pennation angle changes as muscle shortens

Question 34

Types of muscle shapes

Answer 34

- Parallel - Pennate (uni-, bi-, multi-) -circular

Question 35

Parallel muscles

Answer 35

- fibres are parallel with each other and the line of action - pennation angle is 0 degrees - more fibres packed in series, more shortening

Question 36

Types of muscles fibre contraction

Answer 36

- Concentric; muscle shortens - Eccentric; muscle lengthens - Isometric; muscle stays same length

Question 37

Agonist/ antagonist

Answer 37

- antagonistic pairs - agonist is the prime mover - antagonist opposes that movement - Synergist, modifies the action of the agonist