Lab 4 (Unit 2)

Question 1

Skeletal System Functions

Answer 1

• support
• protection
• movement
• blood cell production
• mineral reservoir
• energy metabolism

Question 2

Cartilage

Answer 2

• flexible, resilient

- resists tension and compression

Question 3

Bone

Answer 3

• stronger and stiffer
• mineral reservoir
• muscle attachment sties
• protection

Question 4

Hyaline Cartilage

Answer 4

• most common type of cartilage
• only fiber is collagen
• location: ends of long bones, respiratory structures, embryonic skeleton

Question 5

Bone Tissue

Answer 5

• denser than cartilage (little fluid)
• resists compression and tension
• well vascularized = able to heal and remodel easily
• cells = osteocytes
• extracellular matrix:
  - organic: fibers and ground substance
  - inorganic: 65% mineral salts

Question 6

Skeletal development

Answer 6

• intramembranous ossification (how most flat bones form)

- endochondral ossification

Question 7

Endocondral bone formation

Answer 7

• skeleton beings with hyaline cartilage framework
• week 9 (embryo) primary center of ossification appears in diaphysis and bone cells begin to replace cartilage
• at birth secondary center of ossification forms in epiphyses
• skeleton continues to grow through diffusion of cartilage cells

Question 8

Closure of Epiphyseal Plates

Answer 8

• primary and secondary centers of ossification mean that cartilage is gradually replaced by bone tissue on both sides of the epiphyseal plate
• when centers of ossification meat growth stops

Question 9

Bone remodeling and healing

Answer 9

• bone continuously undergoes remodeling

- if injured cells tend to overgrow at the injury site, which will form a bony callus

Question 10

Osteoporosis

Answer 10

• due to an imbalance in the cycle of bone remodeling (more bone is broken down than built)
• often occurs after menopause because women don’t absorb as much calcium so osteoclasts break down bone to release calcium in the blood stream

Question 11

Compact Bone

Answer 11

• known as cortical
• smooth dense other layer
• strong

Question 12

Spongey Bone

Answer 12

• known as trabecular
• inside bone usually near joints
• more air pockets
• better at shock absorption

Question 13

Compact bone structure

Answer 13

• osteon is the structural unit
• lamellae = concentric tubes that make up an osteon
• osteon’s oriented parallel to long axis
• harvesian (central) canal runs through core of osteon and provides blood supply, nutrients, nerves

Question 14

Axial Skeleton

Answer 14

• 80 named bones
• includes: skull, hyoid bone, vertebral column, thoracic cage
• function:
  - supports head, neck, and trunk
  - protects brain, spinal chord, thoracic organs

Question 15

Foramen

Answer 15

hole in bone typically for nerves or blood vessels

ex: foramen magnum or infraorbital foramen

Question 16

Fossa

Answer 16

depression in bone

ex: mandibular fossa or lacrimal fossa

Question 17

Process

Answer 17

projection from bone

ex: styloid or mastoid process

Question 18

Meatus

Answer 18

hole or tube-like structure

ex: auditory meatus

Question 19

Canal

Answer 19

grove or tube-like structure

ex: optic canal

Question 20

Thoracic Cage

Answer 20

• includes: thoracic vertebrae, ribs, sternum, costal cartilages
• function:
  - protect heart, lungs, and other organs
  - support pectoral girdle and provide attachment points
  
  • intercostal spaces hold muscles that aid in breathing

Question 21

Sternum

Answer 21

• include: manubrium, body, xiphniod process
• articulates with: clavicles, ribs, and costal cartilages
• the sternal angle is an important anatomical landmark = where rib two articulates

Question 22

Rib Cage

Answer 22

• function: protect internal organs and aid in respiration
• 12 pairs of ribs
• all ribs attach posteriorly to thoracic vertebrae
• 1-7 = true ribs; attach to sternum by costal cartilages
• 8-10 = false ribs; costal cartilages don’t directly attach to sternum
• 11-12 = floating ribs; don’t attach anteriorly at all

Question 23

Rib Strucutre

Answer 23

• rib articulates with vertebrae at head and tubercle
• neck is the thinner region between head and tubercle
• head: 2 faces; one articulates with body of its vertebrae and other articulates with vertebrae superior to it
• tubercle: articulates with facet on transverse process of vertebrae

Question 24

Vertebral Column

Answer 24

• 26 vertebrae
• stacked vertebral foramina form vertebral canal for spinal chord
• spinal nerves exit between body of vertebra and neural arch via intervertebral foramina
• functions:
  
  • protect spinal chord
  • supports body axis
  • attachment points for ribs, muscles of neck and back
  • anchors pectoral and pelvic girdle

Question 25

Cervical Vertebrae

Answer 25

- C1-C7 - all have transverse foramen for blood vessels - C1 is atlas - C2 is axis

Question 26

Atlas

Answer 26

- no body of spinous process | - articulates with occipital condyles at superior atricular facet, enables flexion/extension of head (nodding yes)

Question 27

Axis

Answer 27

dens articulates with atlas, enables side to side movement (No)

Question 28

Thoracic Vertebrae

Answer 28

- T1-T12 - articulate with ribs - transverse process with costal facets to articulate with tubercle of rib

Question 29

Lumbar Vertebrae

Answer 29

- L1-L5 | - weight from body focuses here so vertebrae are strong, thicker, wider

Question 30

Sacrum and Coccyx

Answer 30

- sacrum forms posterior wall of pelvis and alae articulate with hip bones - coccyx = tail bone

Question 31

Intervertebral Discs

Answer 31

- cushion between vertebrae - center of disks = nucleus pulposus - outer region = annulus fibrosus

Question 32

Major Sututres

Answer 32

- coronal - squamous - lambdoid - sagittal

Question 33

Fetal/Infant

Answer 33

- skull bones not yet solidly joined - allows head to deform as if passes through birth canal and allows for brain growth - fontanelles = soft spots

Question 34

Parietal Bones

Answer 34

- makes up most of superior part of skull | - includes sagittal suture and lambdoid suture

Question 35

Temporal Bones

Answer 35

- house opening to ear and base of cheekbone - regions: squamous, tympanic, petrous - EAM opening in tympanic region that leads to ear cavities - mastoid process = attachment site for neck muscles

Question 36

Temporomandibular Joint

Answer 36

- jaw joint | - condyle of lower jaw fits into depression in temporal bone (mandibular fossa)

Question 37

Occipital Bone

Answer 37

- posterior of cranium and cranial bones - foramen magnum = large opening in occipital bone that allows for spinal chord to pass through and connect to brain - occipital condyles = region where skull articulates with vertebral column

Question 38

Sphenoid

Answer 38

- large and wing shaped - sella turcica = boney depression that holds pituitary gland - connects face at neurocranium

Question 39

Ethmoid Bone and Nasal Cavity

Answer 39

- ethmoid is just anterior to sphenoid - takes most area between nasal cavity and orbits - separates nasal cavity from bone - cribriformplate: form room of nasal cavity

Question 40

Facial Skeleton

Answer 40

- mandible - vomer - 2 nasals - 2 lacrimals - 2 maxillae - 2 zygomatic's - 2 palatines

Question 41

Orbit

Answer 41

- supports eyes and muscles that moves eyes | - walls formed by frontal, sphenoid, zygomatic, maxillary, palatine, lacrimal, and ethmoid bones

Question 42

Hard Palate

Answer 42

formed by maxillary bone and palatine bone

Question 43

Mandible

Answer 43

- largest, strongest bone in face - contains lower teeth - tooth sockets on superior border = alveolar process - condyle articulates with temporal bone to form TMJ - coronoid process serves as attachment for temporails

Question 44

Teeth

Answer 44

maxilla and mandible are only bones that contain teeth