ANS 2140 - Exam 2 - Skeletal system

Bacterial Chondronecrosis with Osteomyelitis caused by

E. coli, Staph. aureus

Mycobacterium avium characteristics

lameness, necrosis of epithesiayl line/plate

7 skeletal functions

support, protection, Anchorage, mineral and growth factor, blood cell formation, storage, and hormone production

support

framework for organs

protection

protect vital organs (cranium and ribcage)

anchorage

assist skeltal muscle in movement

mineral and growth factor storage

calcium and phosphate

blood cell formation

hematopolesis

storage

fat in yellow bone marrow

hormone production function

regulate insulin, glucose homeostasis, and energy expansion

hormone production example

osteocalin

axiel skelton

core part, protect, support, and carry all other body parts

axiel skelton examples

mandible, skull, rubs

appendicular skeleton (appendage)

bones involved in movement and manipulation the enviornment

appendicular skeleton examples

legs, wings, arms, fingers, toes

what composes skeleton

catilage

3 types of catilage

elastic, hyaline, and fiborous

What type of cartilage is the most abundant?

Hyaline cartilage

What is the appearance of hyaline cartilage?

Frosted glass appearance

What is the primary function of hyaline cartilage?

Important for endochondral ossification

What is the composition of hyaline cartilage?

Layers of collagen and chondrocytes

Where is hyaline cartilage commonly found in the body?

In joints, sternum, nose, and larynx

What type of cartilage is more stretchy?

Elastic cartilage

Where is elastic cartilage commonly found?

In parts of the epiglottis and ear

What is the function of elastic cartilage?

To provide support in areas with a lot of repeated bending and movement

What is the structure of fibrous cartilage?

It has a row of chondrocytes and a row of thick collagen fibers.

What is the function of the thick fibers in fibrous cartilage?

They are there for shock absorption.

Where is fibrous cartilage found?

In the knee, hock, and joints of vertebrae.

composition of bone, two components

without mineral and without collagen

What is the mineral component of bone?

Calcium phosphate, also known as hydroxyapatite.

Does bone contain carbon?

No, bone does not contain carbon.

What property does hydroxyapatite provide to bone?

Hardness.

What are the mechanical properties of bone?

Bone is bending and/or elastic.

What happens to bone when it is subjected to stress?

Bone curls up in shape.

What is the organic component of bone that provides tensile strength? (flexibility)

Collagen

What elements are bones without collagen made of?

Proteins and carbon

What are two types of organic molecules found in bone besides collagen?

Proteoglycans and glycoproteins

What shape is described as resembling a smashed bone?

The shape of bone

framing of bone

inorganic component

ends of bone

epiphysis (distal and proximal)

epiphysis

above the growth

diaphlysis

bone shaft, through the growth

non boney structures

cartilage

Epiphyseal plate

growth is currently happening, present

epiphyseal line

where growth has occured, past

compact bone

makes up outside, hard and dense layer on the walls, internal and near where bone marrow is

spongy bone

honey comb shape within it, more openings, internal and near where bone marrow is

pneumatic bone

contain air sacs that make them alighter bone, vertebre from a bird

medullary bone

contains calcium for egg production

what is an egg shell made of

calcium carbonate

two types of avian bone

medullary and pneumatic

characterists of a avian bone

not hollow

Functional unit of bonr

osteon

osteon

central canal, build up structure around it, lay down matrix and fill in with mineralization

central canal

blood supply and nervous system

lacuna

darker spots within bone, contain cells that are sensing the enviornment

interstitial lamellae

fills the free space

wolves law

use it or lose it, no weight on bone, itll deteriorate

lacunna

detect mechanial stress

5 different cell types in bone

osteogenic, osteoblast, osteocyte, osteroclast, bone lining

What are osteogenic cells?

Stem cells that are mitotically active and can differentiate into other cell types.

What cell types do osteogenic cells differentiate into?

Osteoblasts, osteogenic cells, and bone lining cells.

Where are osteogenic cells located?

On the outside and inside of the bone.

What triggers osteogenic cells to change into other cell types?

Proper signaling.

What are osteoblast cells?

Bone building cells

What do osteoblast cells secrete?

Osteoid (bone matrix)

What do osteoblast cells lay down to provide tensile strength?

A collagen base matrix

What is the function of osteocyte cells?

Monitor and maintain the bone.

Where do osteocyte cells reside?

In lacunae.

What do osteocyte cells monitor?

The health of the bone.

bone lining cells

maintain bone, on outside of the cell

What are osteoclasts?

Bone cutting cells

What do osteoclasts do at the site of resorption?

Dissolve the bone and release calcium

Where do osteoclasts derive from?

Different bone marrow cell types

types of bone growth

formation, remodeline, direction

2 bone formation ways

endocondril osification and intra membranous ossification

What is endochondral ossification?

The embryonic growth of a bone that uses hyaline cartilage as a template.

Which bones undergo endochondral ossification?

All bones besides the scapula and cranium.

intra membranous osification

fibrous backbone

2 ways of direction

lengthening and appositional

lengthning growth

growing at either end, epiphyseal plates being utilized

appositional growth

width or diameter increases

2 ways of bone remodeling

resorption and deposition

reopsorption

osteoclats, comes in and cuts away bone

bone deposition

involves osteoblasts, secrete the osteoid with mineralization following

endochondral ossification

lengthning of bone

top layer

resting zone

first active zone

proliferation zone

proliferation zones

where cartilage undergoes mitosis, hyperplasia

second active zone

hypertonic zone

hypertonic zone

older sartilage cells enlarge, pushing cells out around them up

third active zone

calcification zone

calicification zone

carilage cells die, matrix deteriates, blood vessels envade, undergo calcified

fourth active zone

ossification zone

ossification zone

new bone forms, osteoclast come in and cut matrix then recruit osteoblasts

What is the role of osteoclasts in bone remodeling?

Osteoclasts cut away at the bone matrix and release calcium into the blood.

What signals the recruitment of osteoblasts during bone remodeling?

The activity of osteoclasts signals the recruitment of osteoblasts.

What do osteoblasts do in the resorption bay during bone remodeling?

Osteoblasts secrete new bone matrix.

What occurs after osteoid is laid down by osteoblasts?

Mineralization of the bone matrix occurs.