12. Connective And Adipose Tissue

Question 1

What is connective tissue made up of?

Answer 1

Connective tissue cells
Extracellular proteins/glycoproteins
‘Gels’

Question 2

What are the main cells in connective tissue?

Answer 2

Fibroblasts
Chondrocytes
Osteocytes/osteoblasts/osteoclasts
Stem cells/bone marrow/blood/adipocytes

Question 3

What are the main products of connective tissue?

Answer 3

Fibres
Ground substance
Wax and gel-like materials

Question 4

What are the 3 main components of connective tissue?

Answer 4

Cells
Fibres
Ground substance

Question 5

What fibres re present in connective tissue?

Answer 5

Collagen
Elastin
Reticular fibres

Question 6

What are the functions of connective tissue?

Answer 6

Binding and supporting
Protecting
Insulating
Storing reserve fuel and cells
Transport
Separation of tissues

Question 7

What is another term for loose connective tissue?

Answer 7

Areolar tissue

Question 8

Give 2 examples of loose connective tissue

Answer 8

Submucosa of colon

Superficial layer of dermis in skin

Question 9

What is the structure of loose connective tissue?

Answer 9

Fibroblasts, macrophages WBC, mast cells, adipocytes
2 main fibres - collagen, elastin
Ground substance - proteoglycan

Question 10

What are the functions of loose connective tissue?

Answer 10

Hold vessels that supply fluids
Permits cell migration
Involved in inflammation pathways
Packaging around organs

Question 11

Where is loose connective tissue distributed?

Answer 11

Under epithelial cell layers
Around glands
Surrounding capillaries
Nerves and sinusoids

Question 12

What are fibroblasts?

Answer 12

Synthesise and secrete fibres that lie in ground substance

Important in wound healing process

Question 13

What are myofibroblasts?

Answer 13

Modified fibroblasts
Contain actin and myosin
Responsible for wound contraction

Question 14

What are macrophages?

Answer 14

Phagocytic, degrade foreign organisms and cell debris
Antigen presenting cells
Move into loose connective tissue when local inflammation

Question 15

What are mast cells?

Answer 15

Contains abundant granules

• histamine increases blood vessel wall permeability
• heparin is anticoagulant
• cytokines attract eosinophils and neutrophils

Question 16

What are white adipocytes?

Answer 16

Single,large lipid droplet with nucleus, cytoplasm nd organelles squeezed to one side of cell
Unilocular

Question 17

What is the function of white adipocytes?

Answer 17

Padding and shock absorber
Insulation
Energy reserve

Question 18

What are brown adipocytes?

Answer 18

Multiple small lipid droplets with nucleus, cytoplasm and organelles squeezed to centre of cell
Mainly in neonates
Lots of mitochondria

Question 19

What is the function of brown adipocytes?

Answer 19

Insulation and energy reserve

Question 20

How is heat generated using brown adipocytes?

Answer 20

Oxidative phosphorylation uncoupled

Lipid breakdown accelerated

Question 21

How is heat generated using white adipocytes?

Answer 21

After shivering reflex

Lipid breakdown slow

Question 22

What is the feature of collagen type 1?

Answer 22

Fibrils aggregate into fibres and fibre bundles

90% of all collagen

Question 23

What is the feature of type 2 collagen?

Answer 23

Fibrils do not form fibres

Present in hyaline and elastic cartilage

Question 24

What is type 3 collagen also called?

Answer 24

Reticulin

Question 25

What is the function of reticulin?

Answer 25

Provides supporting framework/sponge | Absent in areolar tissue

Question 26

What is the function of elastin?

Answer 26

Allows tissues to recoil after stretch or distension

Question 27

What is ground substance?

Answer 27

Viscous, clear substance with slippery feel | Composed of proteoglycans

Question 28

What are proteoglycans?

Answer 28

Large macromolecules with core protein which glycosaminoglycans (GAGs) covalently bind

Question 29

What is dense connective tissue?

Answer 29

Fibrous or collagenous tissue | Contains fibroblasts

Question 30

What are the 2 types of dense connective tissue?

Answer 30

Irregular | Regular

Question 31

Describe irregular dense connective tissue and give an example

Answer 31

Fibres running in different directions to resist stresses Collagen 1 fibres in all directions E.g. superficial layer of dermis in skin to prevent tearing

Question 32

Describe regular dense connective tissue and give and example

Answer 32

Fibres running in parallel to each other Collagen 1 fibres in parallel Resist stress in one direction E.g. in tendons that connect muscles to bones

Question 33

What are myotendinuous junctions and what is their purpose?

Answer 33

Skeletal muscle fibres connecting with tendon collagen bundles at junctions provide physiological strength

Question 34

What are tendons?

Answer 34

Connect muscle to bone Very strong Forces transmitted along collagen bundles

Question 35

What are ligaments?

Answer 35

``` Similar to tendons Connect bone to bone Parallel collagen fibres Undulate Wrapped in loose connective tissue (fascicles) ```

Question 36

What are the 3 types of fascia?

Answer 36

Superficial Deep Visceral or parietal

Question 37

What is fascia?

Answer 37

Made up of fibrous connective tissue Flexible Contains closely packed bundles of collagen fibres

Question 38

What are elastin fibres?

Answer 38

Elastin main component of elastic fibres, surrounded by microfibrils In most connective tissue

Question 39

Why is vitamin C important in collagen production?

Answer 39

Required for intracellular production of procollagen | Without, collagen formation disputed

Question 40

What do smooth muscle cells produce?

Answer 40

Elastin, collagen, matrix

Question 41

What is Marfan’s syndrome?

Answer 41

Autosomal dominant Expression of fibrillin 1 gene affected Elastic tissue abnormal

Question 42

What are the signs of Marfan’s?

Answer 42

Abnormally tall Arachnodactyly Joint dislocation Aortic rupture

Question 43

What is osteogenesis imperfecta?

Answer 43

``` Brittle bone disease Mutated collagen fibres do not knit together or not enough produced Weakened bones Short stature Blue sclera Hypermobility ```