Exam 2 Study Guide

Question 1

What is the Skeletal System?

Answer 1

• an organ system with tissues that grow and change throughout life
• includes: bones, cartilages, ligaments, and other supportive CT

Question 2

What are the functions of cartilage? What are the 3 different of cartilages?

Answer 2

Functions: Supports body movement and protects body
1. Hyaline
2. Fibrocartilage
3. Elastic

Question 3

What is the function of Hyaline Cartilage and where is it found?

Answer 3

Function: supports movement of joints between bones
- most common, but also the weakest cartilage
Located in: nose, articular cartilage of a joint, costal cartilage

Question 4

What is the function of Fibrocartilage and where is it found?

Answer 4

Function: serves as a cushion within joints to bear weight/resistance
Located in: cartilage of intervertebral disc and meniscus (pad like cartilage in knee joint)

Question 5

What is the function of Elastic Cartilage and where is it found?

Answer 5

Function: supports flexibility of body parts that need to move
Located in: external ear

Question 6

Bone Covering: What is the Periosteum and Endosteum

Answer 6

Periosteum: irregular CT, covers external surfaces
Endosteum: covers internal surfaces

Question 7

What are the Classifications for bones?

Answer 7

1. long
2. short
3. flat
4. irregular
5. pneumatic
6. sesamoid

Question 8

What is the function of Long Bones?

Answer 8

• provide stability, structure and strength
• made up of epiphysis (2) and diaphysis (1)
  ex. humeros, femur (thigh), radius (connected to thumb in forearm), Ulna (lower forearm), tibia & Fibula (legs), and

Question 9

What are Short Bones?

Answer 9

• enable concentrated movement/articulation
• mobility, strength & support
• short and can be of any shape
  ex. carpal and tarsal bones (cuboid, cuneiform, scaphoid, trapezoid etc.)

Question 10

What are Flat Bones?

Answer 10

• Flat appearance, 2 prominent surfaces, form boundaries of certain body cavities
• made up of 2 compact bones on the outer surface and spongy bone in the middle (sandwich)
  ex. scapula, ribs, sternum etc.

Question 11

What are Irregular Bones?

Answer 11

• shape is irregular and do not fit any category in shape
  ex. vertebrae, hip bones and bones in the base of skull

Question 12

What are Pneumatic Bones?

Answer 12

• have an irregular shape but they have large air spaces that make them lightweight and are found in the skull
• help with resonance of sound and as air conditioning chambers for inspired air
  ex. skull, sphenoid, ethmoid, and maxilla

Question 13

What are Sesamoid Bones?

Answer 13

• in the form of nodules embedded in tendons and joint capsules
• ossification takes place after birth
  ex. patella, pisiform and fabella

Question 14

What are Osteoprogenitor cells?

Answer 14

STEM cells that become osteoblasts

Question 15

What are Osteoblasts?

Answer 15

• IMMATURE
• Secrete osteoid which hardens & produces new bone
• many become osteocytes

Question 16

What are Osteocytes?

Answer 16

• MATURE bone cells
• trapped in a matrix (vomit capsule) & forms callus

Question 17

What are Osteoclasts?

Answer 17

• get rid of excess bone
• remodeling of bone/callus

Question 18

What is Intramembranous Ossification? Name the 4 steps!

Answer 18

• when cartilage develops into bone from mesenchyme or fibrous tissue
  1. Ossification center forms w/ in thickened region of mesenchyme
  2. Osteoid undergoes calcification
  3. Woven (primary) bone and surrounding periosteum form (immature)
  4. Lamellar (mature) -> 2 compact & 1 spongey

Question 19

What are the 4 steps of Intramembranous Ossification?

Answer 19

When bone develops from mesenchyme or fibrous tissue
1. Ossification center forms w/ in thickened regions of mesenchyme
2. Osteoid undergoes calcification (calcium salts being deposited on osteoid and entrap osteoblast
3. Woven (primary) bone and surrounding periosteum form (IMMATURE)
4. Lamellar (MATURE) 2 compact and 1 spongey

Question 20

What is a callus and how is it remodeled?

Answer 20

A callus form to heal a fracture and osteoclasts remodel it and leave a bump.

Question 21

What are the major sets of blood vessels of the bone and what do they supply?

Answer 21

1. Nutrient Artery: main blood vessel that enters the diaphysis. Supply bone marrow in medullary cavity
2. Metaphyseal: enters at the metaphyses to supply blood to the spongey bone
3. Epiphysial: enters at the epiphyses and supply red bone marrow and spongey bone
4. Periosteal Arteries: supplies blood to outer compact bone via haversian canals of osteons
5. Venous system: drains blood away from the bone

Question 22

What makes up the Axial Skeleton?

Answer 22

1. vertebral column
2. thoracic cage (ribs)
3. skull

Question 23

How many bones in human adult?

Answer 23

206
Axial: 80
Appendicular: 126

Question 24

How many bones are in the skull?

Answer 24

22
Facial: 14 no contact w/ brain
Cranial: 8 contact w/ brain

Question 25

What are the Cranial Bones?

Answer 25

PESTOF - Parietal (2) - ethmoid - sphenoid - temporal (2) - occipital - frontal

Question 26

What are the Facial Bones?

Answer 26

VAIN - vomer - auditory ossicles - inferior nasal concha - nasal bone MM - maxilla - mandible PLZ - palatine - lacrimal - zygomatic

Question 27

What are the bones associated with the skull?

Answer 27

1. Auditory Ossiclele (malus, incus, stapes) 2. Hyoid: located inferior to mandible, attachment site for tongue and muscles of larynx used in swallowing

Question 28

What are the 4 sutures? Where do they all meet?

Answer 28

1. Coronal 2. Lambdoid 3. Sagittal (1-3 fuse in late 20's-30's) 4. Squamous (fuse in 60's) They all meet at the Pterion (weakest part of skull)

Question 29

What are fontanels and their 2 roles when they ossify.

Answer 29

Holes in the skull that are made up of dense regular CT 1. Anterior: ossifies @15m 2. Posterior: ossifies @ 9m Two main roles: 1. All skull to get bigger for growing brain 2. Allows for passage through the vagina (molding of head)

Question 30

What is the Thoracic Cage? How many ribs are there?

Answer 30

Bone frame around the chest - 24 ribs in total True Ribs: 1-7 that touch the sternum False Ribs: 8-12 don't touch the sternum Floating ribs: 11-12 don't touch anything

Question 31

What are the landmarks of the scapula?

Answer 31

Articultion: Glenoid cavity where the head of the humerous sits - 3 borders (superior, lateral and medial) and 3 angels (superior, inferior, and glenoid cavity at lateral angle) - spine, acromion process

Question 32

Discuss: Arthritis, Craniosynostosis, kill blow, and cleft palate

Answer 32

Arthritis: Rheumatic disease that affects synovial joints Craniosynostosis: congenital defect that causes one or more sutures on a baby's head to close earlier than norma kill blow: When the Ethmoid bone penetrating the brain. Cleft Palate: When the palate does not fuse together properly in a a developing baby.

Question 33

What are the structural classes of joints/articulation

Answer 33

1. Fibrous: Bones held together by collagen fibers 2. Cartilaginous: bones held together by cartilage and bone separated by fluid 3. Synovial: bones ends are covered with articular cartilage

Question 34

What are the functional classes of joints and how do they move?

Answer 34

1. Synarthroses: immobile joints (MOST STABLE) 2. Amphiarthroses: slightly mobile joints mobile joints 3. Diarthroses: FREELY mobile joints (NOT STABLE)

Question 35

Compare Symphysis Gomphosis and Sychondrosis Syndesmosis

Answer 35

Symphysis (BONES JOINED BY FIBROUS CT) Gomphosis: where teeth articulates between maxilla and mandible ex. front root of tooth -> alveolar process of mandible Sychondrosis (BONES JOINED BY HYALINE CARTILAGE) Syndesmosis: Between parallel bone. Also known as "interosseous membrane". ex. between ulna and radius so the two bones can move as one

Question 37

Describe the following Synovial Joint: Condyloid, Ball and Socket, Saddle, and Hinge

Answer 37

Condyloid: in metacarpals Ball and socket: move in all axis ex. hip and shoulder Saddle: move in multiple axis ex. carpal and metacarbal bones Hinge: movement on one axis -> allows flexion and extension ex. elbow

Question 38

How does the femur articulate?

Answer 38

The femoral head of the proximal femur articulates with the acetabulum of pelvis. Femur head= ball Acetabulum = socket also aarticultes with patella & tibula

Question 39

What is the pelvic girdle?

Answer 39

- strongly attached to axial skeleton (sacrum) - deep sockets - more stable than pectoral girdle - less freedom of movement

Question 40

What bones make up the Os Coxae?

Answer 40

Hip bone made up of 3 separate bones in childhood which fuse (IPI) 1. Ilium 2. Pubis 3. Ischium