Skeletal System

Question 1

5 Functions of the Skeletal System (MSSGG)

Answer 1

1) Movement
2) Support & Protection
3) Store Fat, Iron, & Calcium
4) Generate blood cells
5) Guide growth of body

Question 2

How many bones make up the human body?
Axial Skeleton vs. Appendicular Skeleton

Answer 2

206 bones
Axial Skeleton- 80 bones at body’s midline axis (skull, ribs, sternum, vertebral column)
Appendicular Skeleton- 126 bones grouped into the upper & lower limbs and pelvic & pectoral girdles (allow for movement and anchor muscles)

Question 3

Bone Matrix (5 components, WPCCC) vs. Osteocytes

Answer 3

Oseteocytes- the living bone cells found at the edges of the bone.
Bone Matrix- the nonliving part of the bone
1) water
2) protein
3) collagen
4) calcium phosphate
5) calcium carbonate crystals

Question 4

4 Components of Bone (PCCM)

Answer 4

1) Periosteum- outermost layer, connective tissue, holds osteoblast cells
2) Cancellous Bone- spongy, found at ends of long bones & vertebrae
3) Compact Bone- dense, gives bones strength, made of mineral salts & collagen fibers
4) Marrow

Question 5

Ossification

Answer 5

formation of new bone via Osteoblasts which occurs in fetal development and as bones repair themselves.

Question 6

Osteoclasts

Answer 6

Type of bone cell that breaks down bone tissue in order to help balance the body’s calcium levels (by degrading bone to release stored calcium)

Question 7

Hematopoiesis

Answer 7

Process that creates red & white blood cells from stem cells. Occurs in the red bone barrow.

Question 8

5 Types of Bones

Answer 8

1) Long
2) Short- Carpal bones of wrist & Tarsal bones of foot
3) Sesamoid- Patella, not formed in all people
4) Flat- Ribs, Hips, & lobes of the brain- NO MEDULLARY CAVITY
5) Irregular- Sacrum & Vertebrae

Question 9

Bones of Skull (2)

Answer 9

1) Mandible- jaw bone, only movable bone in skull
2) Cranium- upper part of skull, protection

Question 10

Hyoid Bone- Location and function
Auditory Ossicles- Location & function

Answer 10

1) Hyoid Bone- under mandible, not part of the skull but only bone in body that’s not connected to any one bone. Keeps Trachea open & anchors tongue
2) Auditory Ossicles- close to skull, important for hearing

Question 11

Vertebrae Column (spine)

Answer 11

24 vertebrae plus sacrum & coccyx
C1-C7- Cervical
T1-T12- Thoracic
L1-L5 Lumbar
S1- Sacral
Coccyx

Question 12

Parts of Rib Cage
How many Ribs make up the Rib Cage?

Answer 12

Sternum- aka breast bone, the thin bone along the midline that connects ribs via the Coastal Cartilage
12 Ribs= Thoracic Cage
1-7= True Ribs
8-12= False Ribs
11 & 12= Floating Ribs (protect kidneys)

Question 13

Upper Appendicular Skeleton (PHURCMP)

Answer 13

Pectoral Girldle (clavicle & scapula, connects upper limbs to axial skeleton)
Humerus (upper arm)
Ulna (lower arm, inside bone)
Radius (lower arm, outside bone, allows wrist to turn)
Carpal (8 bones that make up wrist)
Metacarpals (5 bones in hand that connect wrist to fingers)
Phalanges (3 in each finger, 2 in thumb, also in feet/toes)

Question 14

Lower Appendicular Skeleton (PFPTFTMP)

Answer 14

Pelvic Girdle (hips, connects lower limbs to axial skeleton)
Femur (largest bone in body)
Patella (knee cap)
Tibia (bigger, inside bone of lower leg, caries weight of body)
Fibula (outside lower leg bone, anchors muscle)
Talus (one of 7 Tarsal bones that form ankle)
Metatarsla (5 bones in feet that connect to toes)
Phalanges (3 in each toes, 2 in big toe, also in hand/fingers)

Question 15

What is the compact outer layer of bone called?

Answer 15

Cortical