11.8 skeletal system

Question 1

ecdysone

Answer 1

hormone involved in melting and metamorphosis

Question 2

cartilage

Answer 2

avascular connective tissue; softer and more flexible; (ex: ear, nose, larynx,
trachea, joints)
- 3 types: hyaline, fibrocartilage, and elastic.

Question 3

hyaline cartilage

Answer 3

(most common – reduced friction/absorbs shock in joints)

Question 4

cartilage development

Answer 4

from mesenchyme tissue, differentiates to chondrocytes that then secrete
molecules that form cartillagenous matrix (collagen + proteoglycans).

Question 5

how abundant is collagen

Answer 5

most

abundant protein in vertebrates

Question 6

what is collagen surrounded by

Answer 6

dense fibrous connective tissue called

perichondrium. It is derived from the mesenchyme

Question 7

mesenchyme

Answer 7

(the embryonic connective

tissue that gives rise to most connective tissue cells).

Question 8

bone structure

Answer 8

(living) connective tissue; hard and strong, while elastic and lightweight

Question 9

functions of bone

Answer 9

support, protection, assistance in body movement, mineral storage, blood cell production, and energy storage in form of adipose cells in marrow

Question 10

mature bone

Answer 10

woven bone is replaced by lamellar bone. two types are spongy and compact

Question 11

immature. bone

Answer 11

Woven bone is immature and

weak (first bone to form during development and in fracture repair).

Question 12

Chondrocytes

Answer 12

in cartilage

Question 13

fibroblasts

Answer 13

the most common type of cell found in connective

tissue, and are involved in synthesis of ECM. tendons/ligaments/skin

Question 14

Axial skeleton

Answer 14

basic framework (skull, vertebral column, rib cage)

Question 15

Appendicular skeleton

Answer 15

bones of appendages, pectoral and pelvic girdles(basically

everything that isn’t axial). Femur is longest bone.

Question 16

Sutures

Answer 16

immovable joints (holds together bones of skull)

Question 17

Ligaments

Answer 17

bone-to-bone connectors; strengthen joints

Question 18

ACL ligament

Answer 18

connects femur to tibia and limits rotational knee

movement

Question 19

Tendons

Answer 19

dense connective tissue that connects muscle-to-bone; bend

skeleton at moveable joints

Question 20

joint at the shoulder is

Answer 20

ball and socket joint (movement in all planes),

Question 21

knee joint is

Answer 21

hinge joint (movement in one plane only)

Question 22

Origin

Answer 22

point of attachment of muscle to stationary bone

Question 23

Insertion

Answer 23

– point of attachment of muscle to bone that moves

Question 24

Extension

Answer 24

straightening of joint

Question 25

Flexion

Answer 25

bending of joint

Question 26

osteoarthiritis,

Answer 26

cartilage that covers the bone ends of freely movable joints begins to wear away
(due to aging).

Question 27

Rheumatoid arthritis is

Answer 27

a degenerative disorder with a genetic basis.

Question 28

-The foramen is

Answer 28

an opening that allows for the passage of nerves, e.g. the foramen magnum is the skull
cavity that allows passage of the spinal cord.

Question 29

mandible.

Answer 29

strongest bone in face

Question 30

TMJ

Answer 30

attaches the upper and lower jaw.

Question 31

Fibrous joint

Answer 31

connect bones without allowing any movement (Ex: skull, pelvis, spinous process
and vertebrae)

Question 32

cartilaginous joint

Answer 32

bones attached by cartilage, allow little movement (Ex: spine and ribs)

Question 33

Synovial joint

Answer 33

allow for much more movement; most common; filled with synovial fluid which
acts as a lubricant (Ex: carpals, wrist, elbow)

Question 34

Osteoprogenitor/Osteogenic: type of bone

Answer 34

differentiate into osteoblasts [part of the mesenchymal stem cell lineage]

Question 35

Osteoblasts:

Answer 35

secrete collagen and organic compounds upon which bone is formed. Incapable of
mitosis. As they release matrix materials around themselves enveloped by matrix differentiate into osteocytes (remember, Blast means Build)

Question 36

Osteocytes:

Answer 36

incapable of mitosis; exchange nutrients and waste material w/ blood

Question 37

Osteoclasts:

Answer 37

resorb (destroy) bone matrix, releasing minerals back to blood. They have carbonic
anhydrase [recall the rxn it catalyzes]. Develop from WBC’s called monocytes [hematopoietic stem cell
lineage]

Question 38

Compact bone- structure

Answer 38

• highly organized, dense bone that doesn’t appear to have cavities from outside.
• Constantly remodels: osteoclasts burrow tunnels (Haversian canals)
  throughout.
• Osteoclasts are followed by osteoblasts, which lay down new matrix onto tunnel walls forming concentric rings (lamellae). Osteocytes trapped between the lamella (in a space called the lacunae) exchange nutrients via small canals
  (canaliculi). The Haversian canals contain nerves, blood vessels, and lymph vessels;
  they are connected by Volkmann’s canals. The entire system of lamellae + Haversian
  canals is called an osteon (Haversian system). Compact bone surrounds the
  medullary cavity which is filled with yellow bone marrow that contains adipose cells
  for fat storage.

Question 39

YIKES read notes and look at diagrams for this

Answer 39

**

Question 40

rank size of bone structure

Answer 40

osteon is big, then haversian xanal, then canaliculi/osteocyte

Question 41

Spongy (Cancellous) bone-

Answer 41

less dense and consists of an interconnecting lattice of
bony spicules (trabeculae); filled with red bone marrow (site of hemopoiesis - RBC
development)

Question 42

Long bone structure

Answer 42

typically has a long shaft (diaphysis), and two ends (each composed of a metaphysis and epiphysis). Sheet of cartilage between the metaphysis and epiphysis called epiphyseal plate. Bone growth occurs at cartilaginous epiphyseal plates that are replaced by bone in adulthood. Bone increases in length but also in diameter
along the diaphysis as well.

Question 43

bone and calcium levels

Answer 43

In the blood calcium salts only slightly soluble, most is not free ions but bound to proteins or phosphates. Most of the Ca2+ in body is stored in bone matrix as hydroxyapatite (a calcium phosphate mineral) which alongside collagen fibers providing great tensile and compressive strength. Calcium
phosphate (CaHPO4) is the main calcium compound in bone. 99% of calcium in the
body is contained in bones and teeth!

Question 44

hydroxyapatite mineral

Answer 44

If stress is put on a bone, osteoblasts deposit collagen and release calcium
phosphate to strengthen the bone – the mineral hydroxyapatite is produced.

Question 45

Bone Formation Endochondral ossification- cartilage

Answer 45

during FETAL stage of development

bone (EX: long bones; limbs, fingers, toes)

Question 46

Intramembranous ossification

Answer 46

undifferentiated connective tissue replaced by bone

▪ (EX: flat bones; skull, sternum, mandible, clavicles)

Question 47

Haversian canal

Answer 47

contains bone nerves and blood supply

Question 48

periosteum membrane,

Answer 48

bone is surrounded y it. has lots of blood vessels. tendons integrate with it

Question 49

Osteoperosis

Answer 49

causes bone density to decrease, easier to break/fracture. Estrogen can help maintain
bone density (but can increase female risk of blood clots, heart disease, and cancer). Prevention of
osteoporosis: calcium, vitamin D, and exercise.