L5: Connective Tissues

Question 1

What are the four main tissue types?

Answer 1

• Epithelial;
• Connective;
• Muscle;
• Nervous.

Question 2

What is the function of connective tissues?

Answer 2

To provide structural and functional support

Question 3

Give three examples of connective tissues.

Answer 3

• Bone (structural integrity);
• Cartilage (protect joints, structural integrity);
• Tendons and ligaments (connect muscle to bone, protect joints);
• Adipose (energy storage);
• Mesentery (connects intestine to abdomen);
• Layer under skin and around organs (support).

Question 4

Give an example of a connective tissue that provides structural integrity.

Answer 4

Bone

Question 5

What features define connective tissues?

Answer 5

• The extracellular matrix (ECM): ground substance and fibres;
• Cells.

Question 6

What is the general structure of connective tissues?

Answer 6

Cells separated by ECM

Question 7

What is the function of the ECM of connective tissues?

Answer 7

To provide structural and biochemical support for cells

Question 8

What are the two major components of ECM?

Answer 8

• Ground substance;

- Fibres.

Question 9

Which component of the ECM provides biochemical support?

Answer 9

Ground substance

Question 10

Describe the general appearance and composition of ground substance.

Answer 10

Clear, semi-solid gel composed of glycoproteins and complex carbohydrates (such as hyaluronic acid)

Question 11

Other than biochemical support, what are the other roles of ground substance?

Answer 11

• Provide water-binding ability;
• Provide tissue volume;
• Support intercellular exchange.

Question 12

Which component of the ECM provides structural support and tensile strength?

Answer 12

Fibres

Question 13

What are the two main types of fibres within connective tissues?

Answer 13

• Collagen - tensile strength;

- Elastin - stretch and recoil ability.

Question 14

What type of fibre is most abundant in connective tissues?

Answer 14

Collagen

Question 15

What component of connective tissues secretes collagen in to the ECM?

Answer 15

Collagen is secreted from connective tissue cells

Question 16

What type of collagen is found in fibrous tissues? Such as the dermis of the skin, tendons, ligaments and bone

Answer 16

Type I

Question 17

What type if collagen is present in hyaline cartilage?

Answer 17

Type II

Question 18

Whereis type III collagen typically present?

Answer 18

Highly cellular organs such as the liver

Question 19

What component of connective tissues secretes elastin in to the ECM?

Answer 19

Fibroblasts

Question 20

Provide two examples of where elastin is found in large amounts.

Answer 20

• Skin;
• Lungs;
• Vessels;
• Bladder.

Question 21

What are the three major types of cells found in connective tissues?

Answer 21

• xblasts;
• xcytes;
• xclasts.

Question 22

What do xblasts do?

Answer 22

Synthesise ECM (bing bang/blast)

Question 23

What do xcytes do?

Answer 23

Maintain ECM (site/cyte maintenance)

Question 24

What do xclasts do?

Answer 24

Breakdown ECM

Question 25

What are the functions of odontoblasts, adipocytes and osteoclasts?

Answer 25

- Synthesise dentin in teeth; - Maintain ECM in adipose tissue; - Recycle (breakdown) ECM in bone.

Question 26

What is the most common connective tissue cell type and what are their function?

Answer 26

Fibroblasts - Secrete fibres and components of ground substance

Question 27

Which type of connective tissue cell secretes and maintains cartilage within the ECM?

Answer 27

Chondroblasts

Question 28

What do osteoblasts and osteocytes do?

Answer 28

Secrete and maintains mineralised ECM in bone

Question 29

What is the significant difference between epithelial and connective tissues?

Answer 29

Connective tissues are highly vascularised (contain blood vessels and lymphatics- immune cells)

Question 30

What type of connective tissue is not vascularised?

Answer 30

Cartilage

Question 31

What are the two types of 'connective tissue proper' and what determines their type?

Answer 31

- Loose and dense; - Loose, mostly ground substance; - Dense, mostly fibres/proteins.

Question 32

What type of connective tissue is areolar tissue?

Answer 32

Loose connective tissue, 'universal packing material'

Question 33

What are the major functions of adipose tissue (loose CT)?

Answer 33

- Energy storage; - Shock absorption; - Insulation.

Question 34

What is the general structure of reticular tissue (loose CT)?

Answer 34

Branched network of type III collagen, provides internal structure to highly cellular organs e.g. liver, lymph nodes

Question 35

What is the difference between regular and irregular dense connective tissues?

Answer 35

- Regular: closely packed collagen fibres running in the same direction; - Irregular: closely packed, interwoven fibres running in different directions.

Question 36

Provide an example of a regular and irregular dense connective tissue.

Answer 36

- Regular: Tendons/ ligaments; | - Irregular: Dermis of skin and protective capsules or organs.

Question 37

What type of connective tissue has ideal elastic properties?

Answer 37

- Elastic; - Dense, regular CT; - Dominated by elastic fibres; - Lungs, arteries, skin.

Question 38

What component of connective tissue does scurvy, caused by vitamin C deficiency, target?

Answer 38

Collagen, defective formation

Question 39

What type of disease is systemic lupus erythematosis (SLE) and what tissues does it target?

Answer 39

- Autoimmune; | - Skin, bones, tendons, kidneys.

Question 40

What type of disease is Sjogren's and what tissues does it target?

Answer 40

- Autoimmune; | - Glands (tears and saliva).