lecture 2: connective tissue

Question 1

what germ layer is most connective tissue derrived from?

Answer 1

the mesoderm

Question 2

what is the difference between totipotent, pluripotent, and multipotent?

Answer 2

toti-can become anything (anyone!) pluri-any kind of the three germ layers, multi- any cell that is of the germ layer that cell has already initiated

Question 3

the mesenchyme can differentiate into what four types of precursor cells?

Answer 3

fibroblasts, osteoblasts, chondrochondroblasts, hematopoetic cells

Question 4

Besides cells, another component of connective tissue is important to contributing to type and function

Answer 4

fibers, ie collagen, elastic fibers, reticular fibers

Question 5

type I collagen: where is it found, and what might a disorder of this cause?

Answer 5

tendons, ligaments and bones, and stratum fibrosum, lead to very fragile body if defective

Question 6

type II collagen, where is it found?

Answer 6

found in the hyaline cartilige and annulus fibrosis

Question 7

type III cartilige, where is it found

Answer 7

skin and the stratum synovium

Question 8

type XI cartillige, where is it found?

Answer 8

articulating surface of joints

Question 9

epidermolysis bollusa is a disease of what?

Answer 9

collage VII: anchoring collagen

Question 10

what is the role of loose connective tissue, like areolar tissue?

Answer 10

packages organs, surrounds capillaries, under epithelia of body, role in inflamation, cushion, moisture management

Question 11

in what way is the composition of dense connective tissue different than loose?

Answer 11

more collagen, makes it stronger

Question 12

irregular, dense connective tissue eg are

Answer 12

fascia, capsules, periostium, perichondrium

Question 13

regularly arranged tissue eg

Answer 13

ligaments and tendons

Question 14

what about the arrangement of the collagen fibers is different between tendons and ligaments

Answer 14

ligs are less parallel, can withstand small force

Question 15

What are the two layers of the joint capsule?

Answer 15

stratum fibrousum, stratum synovium

Question 16

which layer of the joint capsule is rich in blood supply and poorly innervated?

Answer 16

the synovial layer

Question 17

what is hemarthrosis?

Answer 17

bleeding into the joint space

Question 18

what characterizes the stratum fibrosum?

Answer 18

poor vask, rich innerv esp for pain, inflex, guides!

Question 19

name three functions of tendons, and how its suited to this role

Answer 19

attach muscle to bone, transmit tensile forces for movement, do this efficiently, collagen make up of fiber– inelastic means force is not diminished

Question 20

what makes an apponeuresis so powerful

Answer 20

represents a muscle with a large origin and small insertion

Question 21

what is an example of an elastic ligament?

Answer 21

ligamentum flavum or nuchae

Question 22

cartilage is a modified connective tissue. how does it differ from other CT?

Answer 22

made up of different cells, these differentiate very early in development (chondroblasts) different, stiffer matrix

Question 23

in cartilage, where are the cells (the chondrocytes)?

Answer 23

in lacunae

Question 24

cartilage is avascular. how does it receive nutrients?

Answer 24

either via the perichondrium, or via the synovial fluid

Question 25

what are the two stages of cartilage cell growth?

Answer 25

Interstitial and appositional growth, i, active dividing, ap= no dividing just hypertrophy

Question 26

what surrounds the hyaline cartilage, providing nutrients during development (except for articular cart?

Answer 26

perichondrium

Question 27

two reasons to have articular cartilage

Answer 27

reduces friction and distributes the load

Question 28

difference between osteoarthritis and rheumatoid arthritis

Answer 28

mechanica, restricted to one, vs chronic systemic autommune

Question 29

where would you find elastic cartilage?

Answer 29

ear, epiglottis

Question 30

purposes of bone:

Answer 30

ion resevoir, produce RBC, atatchment for muscles, protection

Question 31

bone can develop two ways, a common and less common way, give examples of each

Answer 31

endochondral, long bones etc, intramembranous ossification where bone dev directly from bone (mandible, scull, clavicle,)

Question 32

in intramembranous ossification, what happens?

Answer 32

precursours (osteoblasts) develop from the mesodermal stem cells. osteoblasts secrete osteoid, which traps them, they become osteocytes.

Question 33

describe endochondral ossification:

Answer 33

from a cartilige model, there is primary and secondary ossification. During primary, chondrocytes differentiate into osteoblasts, begin to deposit bone matrix. there is still a growth plate (cartilige interface)

Question 34

what is the direction of secondary growth in endochondrial ossification?

Answer 34

towards center: chondrocyte layer towards the end, hypertrophic zone towards center of bone=leaves cartilage at the end (articular)

Question 35

different roles for osteoblasts, clasts and cytes

Answer 35

blasts make bone, clasts break it down, cytes sense pressure

Question 36

most of the dry weight of bone is

Answer 36

mineral and collagen

Question 37

volksmans canals, haersian canals=

Answer 37

v passes into bone, h goes along side

Question 38

in mature bone, where are osteoblasts located for growth and repair?

Answer 38

in the inner layer of the periosteum, osteogenic layer

Question 39

what are the two types of bone?

Answer 39

compact, spongy

Question 40

compact bone charicteristics:

Answer 40

found in the diaphysis, has haversian system, support and strength

Question 41

spongy bone charicteristics

Answer 41

composed of trabiculae, found in the epiphysis, red marrow, light weight, make bones springy

Question 42

what is wolfes law?

Answer 42

normal pulling of tendons, weight bearing will shape bones

Question 43

how can movement initiate osteogenisis rather than adipogenisis?

Answer 43

mechanical loading through the bones can make cells preferentially differentiate into bone rather than fat

Question 44

evidence of wolf's law?

Answer 44

weight lifters develop thickenings of insertion on stressed muscles, tennis players hae increased cortical layer on dominant arm

Question 45

what type of fracture is most likely to have severe soft tissue dammage, least?

Answer 45

crushing or penetrating-explosive, tapping

Question 46

tensile force will produce this type of fracture:

Answer 46

transverse

Question 47

axial compression will produce this type of fracture:

Answer 47

oblique

Question 48

spiral fracture is produced by this kind of force

Answer 48

torsion

Question 49

bending force will produce this type of fracture

Answer 49

transverse with small butterfly

Question 50

axial compression and bending will produce this type of fracture

Answer 50

transverse oblique with large butterfly

Question 51

how do blastocytes sense mechanical load?

Answer 51

processes extend into ECM, pressure allows this mechanical signal to be translated into a chemical signal