Musculoskeletal System

Question 0

Diaphysis

Answer 0

shaft of the bone

middle part of bone

Question 1

Physeal cartilage

Answer 1

“area of bone lengthening”
“Growth plate”

where calcifying cartilage and bone meet. osteoblasts make bone here. and cartilage grows here.

Question 2

Epiphysis

Answer 2

end of bone

Question 3

articular cartilage

Answer 3

made of hyaline cartilage

parts of cartilage model that lasts throughout life

Question 4

bone growth during puberty…

Answer 4

when hormones change, cartilage proliferation slows.

osteoblast and osteoclast don’t slow.

Question 5

Medullary cavity

Answer 5

intervening spaces of bone. where red and yellow marrow live.

Question 6

yellow marrow

Answer 6

fat storage.

in adults

Question 7

Red Marrow

Answer 7

active hematopoiesis (makes RBCs)
in young animals

Question 8

Cortex

Answer 8

dense outer core of bone

Support pieces

Question 9

Periosteum

Answer 9

connective tissue membrane around the MATURE bone

Question 10

Endosteum

Answer 10

connective tissue membrane that lines the medullary cavity

Question 11

Cancellous bone

Answer 11

(spongy or trabecular)
inner meshwork of bone. the internal struts.

[studs of a house]

Question 12

direction of bone growth in long bone

Answer 12

outward

Question 13

direction of cartilage growth in long bone (endochondral ossification)

Answer 13

inward

Question 14

Muscle as an organ

Answer 14

highly specialized to do ONE thing = shorten/attempt to shorten
Has tissues (skeletal mm., connective, nervous)
has motor unit

Question 15

Function of muscle as an organ

Answer 15

• myocytes: shorten/attempt to shorten
• produce mvmt of bones and organs
• prevent movement (stabilize jt - the attempt to shorten part)

Question 16

Motor Unit

Answer 16

neuron and group of associated muscles

functional contractile unit of m.

Question 17

Precision of muscles determined by…

Answer 17

myocytes/neuron

low ratio: very precise
moderate ration: fine control (in our hands)
high ratio: general power (cranial arm)

Question 18

origin of muscle

Answer 18

more proximal attachment

tends to be area that doesn’t move

Question 19

Muscle blood supply

Answer 19

get it to different parts by same general large vessel

Question 20

Intramembranous ossification

Answer 20

no cartilage model
uses connective tissue membrane and lays down bone under it
flat bones made this way.

Question 21

Endochondral ossification
(general description)

Answer 21

cartilage model
long bones made this way
4 overlapping phases

Question 22

Phase 1 endochondral ossification

Answer 22

formation of cartilaginous model

- same shape as mature bone
- solid rod of hyaline cartilage
- perichondrium surrounds most of it
- no bone tissue or blood vessels

Question 23

2nd phase of endochonral ossification

Answer 23

formation of primary center of ossification

Question 24

Center of ossification

Answer 24

distinct site where bone tissue develops

Question 25

Osteoprogenitor cells

Answer 25

become osteoblasts, osteoclasts, and osteocytes when blood vessels grow toward it.

Question 26

Osteoclasts

Answer 26

‘eats’ Ca.

the calcified cartilage and calcified osteoid matrix

Question 27

Osteoblast

Answer 27

secrete osteoid

‘bone’ + ‘forming’

Question 28

Osteocytes

Answer 28

driven by hormones.

mature bone cells (not growing anymore. adults primary bone cell type)

Question 29

Secondary centers of ossification

Answer 29

at least one per long bone.

not all bones have them (aka short bones)

Question 30

Long Bones

Answer 30

elongated on 1 axis
expanded ends
humurus

Question 31

Short bones

Answer 31

Cuboidal
Many articular surfaces
bones of carpus and tarsus

Question 32

Flat Bones

Answer 32

expanded in 2 axes

Scapula, os coxae, ribs

Question 33

Irregular Bones

Answer 33

numerous projections

vertebrae

Question 34

Sesamoid bones

Answer 34

embedded (typically in tendons)
protect and redirect
patella, proximal sesamoid bones in manus

Question 35

Pneumatic Bones

Answer 35

air-filled spaces

mammals’ sinuses, mostly in birds though

Question 36

Axial skeleton

Answer 36

central axis (median plane)
primary job = support and protect
skull, vertebral column, ribs

Question 37

Appendicular Skeleton

Answer 37

primary job = lever for locomotion

limbs (scapula/pelvis down)

Question 38

Bone functions

Answer 38

1. Physical: support, protect, lever for mvmt

2. Metabolic: Ca and P reservoir, fat storage, hematopoiesis (making RBC/WBC)

Question 39

Bone the tissue

Answer 39

Bone cells (osteoblast, osteoclast, osteocytes)
extracellular material (osteoid)