Connective Tissue II Flashcards
which cells make up adipose tissue?
what makes up adipose tissue?
function of adipose tissue?
what are two types?
adipose tissue
made from: adipocytes
function: energy homeostasis, insulation, endocrine function
t_wo types:_ white and brown adipose tissue
describe what white adipose tissue looks like
appearance:
- large, white and spherical
- flat nucleus on periphery of cell
- cytoplasm appears empty (components arent preserved after histological staining)
location:
- subcut
- mammary glands
- visceral pericardium
when is brown adipose tissue present in human life? why?
whats appearance like?
brown tissue:
when?
- present during fetal life, but diminishes after first decade
- why?: important role in thermogenesis: met. of lipids to generate heat
appearance
- smaller cells
- nucleus in eccentric position, but not flat (appears black / dark in picture)
- brown colour from high levels of cytochrome oxidase in mitochondria
- cytoplasm has empty vacuoles
what is cartilage made from?
is it vascular ?
cells: chondrocytes, ECM = 95%.
contains:
- avascular: ECM crucial for surivial
- glycosaminoglycans (GAGs)
- few type II collagen fibres
what are the three types of cartilage?
hyaline cartilage
elastic cartilage
fibrocartilage
how is cartilage made?
- chondroblasts (immature chondrocytes): produce and deposit collagen type II and ECM.
- chondroblasts become trapped within matrix spaces (lacunae): become chondrocytes
- *2 mechanisms for formation of cartilage:**
- *a) interstitial growth:** from chondrocytes within the cartilage
b) appositional growth: undiff. cells at the surface of the cartilage (perichondrium)
when interstitial growth is occuring, what are the territorial and interterritorial matrixes?
interstitial growth:
territorial matrix: matrix in close contact with chondrocyte
interterritorial matrix: matrix that seperates the clustered chondrocyrtes enveloped by territorial matrix
with regards to appositional growth:
what is the perichondrium?
what do perichondrium inner cells differentiate into ?
(Appositional growth: formation of caritlage from undifferentiated cells at the surface of the cartilage or perichondrium.)
Perichondrium: reticular fibrous layer by clustered outermost cartilage cells, the zone between cartilage and surrounding general connective tissue.
Perichondrium inner cells differentiate into chondroblasts – (synthesize/secrete collagen II and ECM components)
New cell layers and ECM are added to the surface of the cartilage.
what is the most abundant type of cartilage?
- most abundant cartilage: hyaline cartilage
what is structure of hyaline cartilage like?
contents?
function?
surrounded by?
Contents: collagen II fibres, GAGs and glycoproteins.
Structure: Chondrocytes in spaces in the matrix called lacunae
Function: Low-friction surface, lubrication of joints and tension absorption (temporary skeleton of embryo, articular cartilage, and cartilage of respiratory tract and coastal cartilages)
Surrounded by: a dense connective tissue layer called perichondrium (except articular cartilage)
elastic cartilage:
characterised by?
location?
surroundered by?
(same structure with lacuna and chondrocytes)
charactised by: elastic in ECM
location: ear and epiglottis of larynx
Surrounded by: perichondrium
fibrocartilage:
- structure?
- location?
- common?
fibrocartilage:
structure: fibroblasts and chondrocytes surrounded by collagen I and less rigid ECM. NOT surrounded BY PERICHONDRIUM.
- looks wavy and chondrocytes are sparsely scattered
location: present in invert discs, pubic symphysis, menisic of knee joint and places where tendons attach to bones
(- not that common (esp. compared to hyaline cartilage))
bone:
main characteristic?
components?
main characteristic: mineralised ECM - gives hardness. lots of it.
components:
- mineralised ECM
- collagen type I
- lacuna
- Proteoglycans
- Glycoproteins
- Bone specific vit. K-dependent proteins
(immature bone looks similar to cartilage - development is similar)
what are the three archictetural patterns of bone?
what supplies blood to bones?
what connects ^?
- circumferential outer layer
- concentric - forms the osteons (looks like circles)
- interstitial - between 1 & 2.
also have:
- harversion canal in the osteons: tubes where BV fill
- volkmann’s canals: connect the haversion canals
what are the three mane types of bone cells?
- osteoblasts: bone formation - immature bone cells
- osteocytes: bone maintenance -
- osteoclasts: - bone resorption / remodelling. multi nucleited (osteoclast, large multinucleated cell responsible for the dissolution and absorption of bone. Bone is a dynamic tissue that is continuously being broken down and restructured in response to such influences as structural stress and the body’s requirement for calcium)
functions of blood tissue?
Delivery of nutrient, hormones, regulatory substances and oxygen to the tissues
Transport of wastes and carbon dioxide away from the tissues
Maintenance of homeostasis as buffer
Transport of immune “players
what are three types of muscle cells?
skeletal muscle
cardiac muscle
smooth muscle
basic feature of skeletal muscle?
long, cylindrical, multinucleited cells
obvious striations
basic features of cardiac muscle?
- branched chain of cardiac muscle cells
- intercalated discs (lines between chains)
- striations
basic features of smooth muscle
no striations
spindle cell shaped
uninucleate
what are prominat features of CNS and PNS cells?
prominant features:
CNS:
a) neurons b) glial cells
PNS:
a) Ganglia (groups of nerve cell bodies) b) nerve fibres (axons and Schwann cells)
