Connective Tissue II

Question 1

which cells make up adipose tissue?

what makes up adipose tissue?

function of adipose tissue?

what are two types?

Answer 1

adipose tissue

made from: adipocytes

function: energy homeostasis, insulation, endocrine function

t_wo types:_ white and brown adipose tissue

Question 2

describe what white adipose tissue looks like

Answer 2

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

Question 3

when is brown adipose tissue present in human life? why?

whats appearance like?

Answer 3

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

Question 5

what is cartilage made from?

is it vascular ?

Answer 5

cells: chondrocytes, ECM = 95%.

contains:

• avascular: ECM crucial for surivial
• glycosaminoglycans (GAGs)
• few type II collagen fibres

Question 6

what are the three types of cartilage?

Answer 6

hyaline cartilage

elastic cartilage

fibrocartilage

Question 7

how is cartilage made?

Answer 7

- 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)

Question 8

when interstitial growth is occuring, what are the territorial and interterritorial matrixes?

Answer 8

interstitial growth:

territorial matrix: matrix in close contact with chondrocyte

interterritorial matrix: matrix that seperates the clustered chondrocyrtes enveloped by territorial matrix

Question 9

with regards to appositional growth:

what is the perichondrium?

what do perichondrium inner cells differentiate into ?

Answer 9

(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.

Question 10

what is the most abundant type of cartilage?

Answer 10

• most abundant cartilage: hyaline cartilage

Question 11

what is structure of hyaline cartilage like?

contents?

function?

surrounded by?

Answer 11

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)

Question 12

elastic cartilage:

characterised by?

location?

surroundered by?

Answer 12

(same structure with lacuna and chondrocytes)

charactised by: elastic in ECM

location: ear and epiglottis of larynx

Surrounded by: perichondrium

Question 13

fibrocartilage:

• structure?
• location?
• common?

Answer 13

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))

Question 14

bone:

main characteristic?

components?

Answer 14

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)

Question 16

what are the three archictetural patterns of bone?

what supplies blood to bones?

what connects ^?

Answer 16

1. circumferential outer layer
2. concentric - forms the osteons (looks like circles)
3. interstitial - between 1 & 2.

also have:

• harversion canal in the osteons: tubes where BV fill
• volkmann’s canals: connect the haversion canals

Question 17

what are the three mane types of bone cells?

Answer 17

1. osteoblasts: bone formation - immature bone cells
2. osteocytes: bone maintenance -
3. 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)

Question 18

functions of blood tissue?

Answer 18

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

Question 19

what are three types of muscle cells?

Answer 19

skeletal muscle

cardiac muscle

smooth muscle

Question 20

basic feature of skeletal muscle?

Answer 20

long, cylindrical, multinucleited cells

obvious striations

Question 21

basic features of cardiac muscle?

Answer 21

• branched chain of cardiac muscle cells
• intercalated discs (lines between chains)
• striations

Question 22

basic features of smooth muscle

Answer 22

no striations

spindle cell shaped

uninucleate

Question 23

what are prominat features of CNS and PNS cells?

Answer 23

prominant features:

CNS:

a) neurons b) glial cells

PNS:

a) Ganglia (groups of nerve cell bodies) b) nerve fibres (axons and Schwann cells)