Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Histology Fall 2012 > Cartilage & Bone > Flashcards

Cartilage & Bone Flashcards

1
Q

What do chondrocytes manufacture and secreate?

A

Collagenous precurser procollagen–> modified in the ECM into tropocollagen

latter forms various cross-links to form a collagen FIBRIL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Can you see fine fibrillar matrix of cartilage under LM?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the amorphous ground matrix composed of

A

AGGRECAN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is the entire amorphous matrix contained?

A

within the spaces between the type 2 collagen fibers

Fibers and amorphous ground substance form a alttice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is function of collagen and aggrecan?

A

Collagen- provides tensile strength

Aggrecan contains high concentration of negative ions to bind large quantities of water molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is function of cartilage ECM

A

space-holding network ,formed of immobilized water

Serves as a shock absorber, releasing water when under compression and attracting water when the compressive force is removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does cartilage tissue develop from?

A

mesenchymal cells that migrate, aggregate, cndense, and give rise to chondrogenic (precursor) cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Mesenchymal cells?

A

develop into chondrblasts –> chondroblst secrete ECM around itself –> now completed embedded in ECM in a space called a lacuna!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Mature cell is called?

A

Chondrocyte!

Contain large amounts of RER b/c they manufacture large amounts of collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the function and location of Hyaline Cartilage? (5)

A
  1. Fetal Skeleton
  2. Anterior Portion of the Ribs (costal cartilage)
  3. Structural support of the trachea and bronchi
  4. Articular surfaces of synovial joints
  5. Epiphyseal (growth) plate in long bone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a synovial joint composed of?

A

Fibrous Capsule

synovial membrane (whcih secretes synovial fluid)

Articular surface of hyaline cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Does articular surface have perichondrium?

A

No! It gets diffusion of oxygen and nutrients from synovial fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Perichondrium surrounds all cartialge exept where?

A

Articular surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the composition of Elastic Cartilage?

A

Type 2 collagen & elastic fibers

Provide an increased amt of flexibility designed to withstand repeated flexiosn and extensions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where can you find Elastic Cartilage?

A

In structures that must withstand repeated bending,

such as auricle of ear,

external auditory canall,

Estachian tube, epiglottis,

and the larynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What kind of stain is needed to see Elastic fibers?

A

Not with H&E

Specific Stain is required to definitely identify this tissue, bye staining elastic fibers BLACK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe what Elastic cartilage looks like?

A

Covered by perichondrium and contains chondroblasts and chondrocytes in lacunae.

IT also contains the same ECM components as allohter cartalge

Type II colalge, minor colalgens, same amorphous ground substance`

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What two components make up elastin fibers?

A

Fibrillin fibers with an elastin core

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What kind of fibers are in Fibrocartilage

A

Usual ECM components, also contains TYpe I Colalgen Fibers

Presence of Type I colalgen in fibrocartilage ECM makes it tougher than hyaline or elastic cartilage, but also makes it resistant to compressive forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where can you find Fibrocartilage?

A

symphysis pubis

intervertebral disks

menisci of knee joint

attachment points of tendons to bones

Provides resistance to particularly strong forces beign exerted at these locations and it also provides flexibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What color does it stain?

A

Presence of Type I colalgen fibers makes fibrocartilage stain pink with H&E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Does it have a perichondrium?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the layers of the intervertebral disck

A

acts as shock abosrber between vertebrae

oval-shaped disk has 2 parts
1. center- nucleus pulposus that contins mesenchymal cells in viscous fluid of hyalaurinc acid

  1. outer regularly arranged concenetrc fibrocartilage layers = annulus fibrosus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

In young, how is cartilage repaired?

A

repair form damage occurs through replacement of chondroblasts generated from chondrogenic layer of perichondrium

25
Q

IN adults, ?

A

Cartilage repair occurs poorly or not at all

Hwne cartilage in kenee is torn, natural healing process favors either formatino of scar tissue (Fibrous CT, generated from fibrous layer of perichondrium) or bone deposition

26
Q

Under what conditions favor cartilage formaiton?

A

when oxygen pressure is low,

usually not the case in a wound where blood is bing delivered quickly as part of normal immune and healing repsonses

High oxygen concentrations favor development of bone

27
Q

What is a consequence of cardiothoracic surgery?

A

costal cartilage is severed to open chest ccavity for heart repair– ribs have to be wired back to sternum

one after-effect can be arthritis of rib cage

28
Q

What is bone?

A

Specialized CT and organ

29
Q

What kind of tissue types are in bone (the organ?)

A

CT fibers, hemopoietic tissue, nerves, vasculature, lymphatics, fat, cartialge, bone tissue

30
Q

Bone as organs are classified as (4)

A
  1. long bones (upper and lower extremities)
  2. short bones (hands and feet)
  3. flat bones (skullbones, breastbone)
  4. Irregular oones (vertebrae, mastoid bone)
31
Q

What are the functions of bone?

A
  1. Form jointed skeletal system of the bond-
    ligaments and provide attachemtn sites for sk muscle
  2. protect vital organs-
    skull encase brain, thoracic cage, pelvis protects reproductive
  3. Contain bone marrow
    - new blood cells formed
  4. provide reservoir for Ca and Pi ions
    growth facotrs and other minerals
32
Q

What is the ECM of bone composed of?

A
  1. organic portion that forms template for mineratlized protein
33
Q

What is organic protion called? what does it contain?

What kind of fibers ?

A

Osteoid- contains amorphous ground substance and fibers

ground substance is composed of proteoglycans

fibers are predominatly Type I collagen

34
Q

Where does their assembly take place?

A

Extracellulary from precursor molecuels syntehsized and secreted by osteblasts

35
Q

What is the principla mineral component of EC in bone?

A

Calciumm Phosphate (hydroxyapetite) , present in crystalline form

36
Q

What two methods are used to prepare bone from LM examination?

A
  1. Ground bone method

2. Demineralization (decalcification)

37
Q

What is the Ground Bone Method?

A

Bone is thinly sliced and finely ground

Calcified matrix is preserved but cellsa re lost

38
Q

What is the Demineralized Method?

A

bone is fixed, calcium phosphate is removed, and remianing material is embedded, sectioned, and stained with H&E stained

Fixation process preserves cells and organic portion of ECM (mostly collagen fibers)

39
Q

What are osteoblasts? waht do they produce?

A

Basophilic, cuboidal cells taht secrete organic componetn of ECM.

Produce ALKALINE Phosphatase, procolalgen, and non-collagenous proteins that have a role in calcification.

40
Q

What stimulates Osteoblasts?

A

Vitamin D, Calcitonin, estrogen, and grotwht factors

The also contain receptors for parathryoid hormone, which inhibits their activity and stimulates osteoclast activity

41
Q

When does calcification begin?

A

When osteoblast’s secretions lower pH around teh cell

Alkaline phosphatase rleases free phosphate ions; these combinde with calcium ions and ppt as crystlas of calcium phospahte

low pH is required for this step

42
Q

What cells do osteoblasts originate from? Where are they found?

A

osteoblasts originate from OSTEOPROGENITOR CELLS in teh periosteum and in BM

capabe f active cell division

Found ining endosteal and periosteal surfaces of actively-growing one and maintain communication with each other by means of gap junction

43
Q

How doe osteoblasts stay in contact? What is prominent in their structure?

A

Communicate with each otehr thorugh gap unctions and have a prominent Golgi apparatus and rER since they make a lot of cells and rlease large amounts of proteins

44
Q

What are osteoclasts? Function?

A

Multinucleated macrophae

under hormonal control, osteoclast uses low pH and preoteases to digest bone

Resorbs bone

45
Q

what do osteoclasts secete?

A

H+ ions to raise extracellular pH, then secrete acid phosphatase–> dissolves calcium phospahte matrix of bone

Also release collagenase which digests old collagen fibers

46
Q

What stimulates osteoclasts?

A

Stimulated indirectly by Parathyroid hormone (PTH), and inhibited directly by CALCITONIN, which binds to specific receptors on their surface

47
Q

Do osteoclasts begin digestive process extracellulary or intracellulary?

A

Extracellulary by secreting lysosomal-like enzymes like acid phsophatase and collagenase nto lumen adjacent to their ruffled border

48
Q

What happens during bone remodeling and when does it occur?

A

Osteoclast resorption, osteoblast activity (matrix formation steoid), mineralization, resting phase

Remodleling takes palce during normal bone maintenance, repair of bone fractures and in response to increased bone loading (lifting weights leads to thicker, stronger bones)

49
Q

What are contained in Haversian canacls and Volksmann’s canals?

A

Veins, arteries, lymphatics, nerve processes

Broken bones are painful and bone breakage always involves bleeding

50
Q

what are canaliculi

A

canaclas taht extend between lacunae

processes of adjacent osteocytes communicate via gap junctions

all osteocytes are conencted to Haverisan canal which provides their nourishemnt

51
Q

What is PERIOSTIEUM

A

outer covering with two layers,

outer, fibrous layer (similar to dense CT0 and inner cellular layer

covers external surface of bone, contains a reservoir of osteoblasts for new appositional bone formation

attachemtn point for muscles, tendons and ligaments

52
Q

what are Shaerpye’s fibers

A

Type I colalgenous fibers that exend into bone, anchioring it firmly’ fibers are found wherever a strong aattachemnt to bone is required

attachemtn if furtehr strengthened by thickening of the periosteum wherever bones, tendons, or laigament attach

53
Q

what kind of cellsa re in teh inner layer of periostieum?

A

contain osteoprogenitor ells which give rise to osteoblasts

54
Q

What are two types of ossificaiton? Two ossficaiton differ with respect to starting material

A

1 can be mesenhyme

2. oe XERILfw

55
Q

What does low oxygen levels favor?

A

development of cartialge

56
Q

What does high oxgyen levels favor?

A

development of bone

57
Q

What is intramembranous ossification?

A

bone forms direclty within layer of condensed mesenchyme

bone generated from within the MEMBRNAE

CARTILAGE is NOT invovled in this process at all

Mesencymal cells differentiate directly into OSTEOPROGENITOR celsl (bone precursr ) cells –> osteoblast

58
Q

Periosteal layer

A

jj

Histology Fall 2012 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions