General connective tissue L4

Question 1

What are the functions of connective tissue? HINT THERE ARE 5

Answer 1

Structural framework, transports fluids and dissolved materials, stores lipids, protects organs and defends the body from pathogens

Question 2

General connective tissue can be split up into what 3 categories?

Answer 2

Cells, fibres and ground susbtance

Question 3

What is ground substance?

Answer 3

Ground substance fills the spaces between cells and fibers. It is a gel like extracellular matrix that adds strength and stiffness. It also delays the spread of infection

Question 4

What does ground substance contain?

Answer 4

Water and salts
Glycosaminoglycans (GAGs)
Proteoglycan molecules

Question 5

What are GAGs - Glycosaminoglycans?

Answer 5

Polysaccharides, made up of sugars

Question 6

What do Proteoglycan molecules do?

Answer 6

They bind to water giving a gelatinous property to the matrix. They also form aggregates to make up ground substance.

Question 7

What does ground substance seem to be in preparations?

Answer 7

In preparations, ground substance seems to be structureless and stains metachromatically with toluidine blue

Question 8

What are the commonest GAGs?

Answer 8

Hyaluronate, chondroitin-4-sulphate, chondroitin-6-sulphate, dermatan sulphate, heparin sulphate and keratan sulphate

Question 9

What is the predominant GAG?

Answer 9

Hyaluronate - hyaluronic acid and it is important because the viscosity of ground substance depends on the content of it

Question 10

What is the ground substance elaborated by?

Answer 10

By the endoplasmic reticulum of connective tissue cells, especially of fibroblasts

Question 11

Connective tissue components:

Answer 11

Cells and fibres in a matrix

Question 12

Cells in connective tissue?

Answer 12

Mesenchymal cells, fibroblasts, adipocytes (fat cells), immune cells

Question 13

What are the immune cells in connective tissue?

Answer 13

Macrophages/monocyte, mast cells, B cells/plasma cells and lymphocytes

Question 14

What fibres are in connective tissue?

Answer 14

Collagen and elastin

Question 15

Is there one ancestor of connective tissue cells?

Answer 15

Yes there is one ancestor - mesenchymal stem cells

Question 16

What are the 7 cells of connective tissue?

Answer 16

Mesenchymal stem cells (MSCs)
Fibroblasts
Adipocytes (fat cells)
Macrophages (Histiocytes)
Mast cells
B cells/ Plasma cells
T cells

Question 17

What is the basic function of mesenchymal stem cells (MSCs)?

Answer 17

Differentiate into other cells

Question 18

What is the basic function of fibroblasts?

Answer 18

Make extracellular matrix, wound healing

Question 19

What is the basic function of adipocytes (fat cells)?

Answer 19

Stores and metabolises fat

Question 20

What is the basic function of macrophages (Histiocytes)?

Answer 20

Phagocytic, innate immune cell

Question 21

What is the basic function of mast cells?

Answer 21

Histamine reactions, innate immune cells

Question 22

What is the basic function of B cells/Plasma cells?

Answer 22

Make antibodies, adaptive immune cell

Question 23

What is the basic function of T cells?

Answer 23

Major immune cell, adaptive immune cell

Question 24

Are MSCs multipotent?

Answer 24

Yes

Question 25

Can MSCs differentiate into all other cells found in connective tissue?

Answer 25

Yes

Question 26

Where are MSCs obtained from?

Answer 26

Bone Marrow

Question 27

Can MSCs act as a potential use for cell replacement therapy?

Answer 27

Yes

Question 28

What is the most abundant cell in connective tissue?

Answer 28

Fibroblasts

Question 29

Can fibroblasts differentiate into different cells?

Answer 29

Yes

Question 30

What do Fibroblasts make?

Answer 30

Extracellular matrix, i.e. secrete components: GAGs, collagen, elastin, ground substance

Question 31

What immune response do fibroblasts play a role in?

Answer 31

They have a role in wound healing i.e. they secret collagenous matrix (scar tissue)

Question 32

Where do adipocytes develop from?

Answer 32

Fibroblasts

Question 33

Can mature adipocytes divide?

Answer 33

NO

Question 34

What do fat cells do? hint 5

Answer 34

They support and protect organs They store and metabolise fat (lipid) They insulate (slow heat loss)

Question 35

What do white adipose cells do?

Answer 35

They store energy. Role: insulation, shock absorption

Question 36

What do brown adipose cells do?

Answer 36

They heat the body Role: Stores energy in fat

Question 37

What are the 3 places where the birth of a macrophage happens?

Answer 37

Bone marrow, Blood, Tissue

Question 38

5 steps within cells to birth of a macrophage:

Answer 38

stem cell -> monoblast->monocyte->macrophage->activated macrophage

Question 39

Are macrophages phagocytic?

Answer 39

Yes

Question 40

Do macrophages scavenge foreign materials?

Answer 40

Yes bacteria, debris, etc

Question 41

What else can macrophages be called?

Answer 41

Monocytes and histiocytes

Question 42

What immune system are macrophages apart of?

Answer 42

The innate immune system

Question 43

Where are fixed macrophages found at?

Answer 43

Strategic points

Question 44

What do macrophages have for degradation?

Answer 44

They have lysosomes for degradation

Question 45

What are 6 places where fixed macrophages are found?

Answer 45

1. Dust/Alveolar type (lungs) 2. Histiocytes (connective tissue) 3. Kupffer cells (liver) 4. Microglial cells (nervous) 5. Osteoclasts (bone) 6. Sinusoidal lining cells (spleen)

Question 46

What do macrophages do in order to respond to pathogens?

Answer 46

They present pathogen antigens at their cell surface to T cells (elicit an adaptive immune response)

Question 47

What 3 disorders are associated with macrophages:

Answer 47

Granuloma, Macrophage Activation Syndrome, and Multicentric reticulohistiocytosis

Question 48

What are leprosy and TB resistant to?

Answer 48

They are resistant to lysosomal degradation

Question 49

What was the plague pathogen resistant to?

Answer 49

Phagocytosis

Question 50

Where does HIV virus replication occur?

Answer 50

In macrophages

Question 51

What do macrophages do in infected throat cells?

Answer 51

They destroy influenza

Question 52

Do macrophages play a role in atherosclerotic deposits?

Answer 52

Yes

Question 53

Do macrophages play a role in atherosclerotic deposits?

Answer 53

Yes

Question 54

What do macrophages release with tumour cell proliferation?

Answer 54

They release growth factors