Connective Tissues

Question 1

What is the most abundant tissue in the body?

Answer 1

Connective tissues

Question 2

What is the function of connective tissues?

Answer 2

Provide structural and functional support to other tissues and organs they comprise

Question 3

Give examples of connective tissues? (6)

Answer 3

1. Bone - structural integrity
2. Cartilage - protect joints, structural integrity
3. Tendons and ligaments - connect muscle to bone, protect joints
4. Adipose tissues - energy source
5. Mesentery - connects intestine to abdomen
6. Layers under skin & around organs - support

Question 4

What 3 features define connective tissue?

Answer 4

Ground substance
Fibres
Cells

(1+2= extracellular matrix)

Question 5

What differs in the arrangement of cells in epithelial and connective tissues.

Answer 5

In connective tissues cells are separated by the extracellular matrix

I’m epithelial tissues cells are tightly bound

Question 6

What does the extracellular matrix do in connective tissues ?

Answer 6

Provides structural and biochemical support to the cell.

Most mass comes from ECM

Question 7

Describe the ground substance.

Answer 7

• clear semi solid gel
• provides biochemical support
• composed of glycoproteins and complex carbs (hyaluronic acid/ glucosamine)
• water binding ability
• provides tissue volume
• supports intracellular exchange of substances
  = substances produced by one cell can diffuse through GS to reach nearby cells

Question 8

Describe fibres.

Answer 8

Function: provide structural support and tensile strength
2 types = collagen & elastin

Both secreted into ECM by connective tissues

Question 9

What is collagen?

Answer 9

Strongest & most abundant provide tensile strength

Question 10

What is elastin?

Answer 10

Long and branched
Provides stretch and recoil ability

Question 11

Describe the collagen alpha helix in connective tissues.

Answer 11

1 collagen molecule forms alpha helix with 3 more to form triple helix structure.

Numerous of these join together to form individual collagen fibrils and numerous fibrils come together to form collagen fibre

VERY STRONG

Question 12

How many types of collagen is there?

Describe the main 3.

Answer 12

28

1.found in fibrous tissues (dermis of the skin, tendons, ligaments, bone)
2.hyaline cartilage
3.delicate branched ‘reticular’ network found in highly cellular organs (liver)

Question 13

What does elastin do and where is it found?

Answer 13

Confers elasticity to tissues

Found in large amounts in:
Skin
Lungs
Blood vessels
Bladder

Question 14

What is the function of a fibroblast?

Answer 14

-synthesise ECM
-most common type of connective tissue cells
-give rise to more specialised cells
-secrete fibres/components of GS

Question 15

What is the function of odontoblasts?

Answer 15

Synthesise ECM

synthesise Dentin in teeth

Question 16

What is the function of adipocytes?

Answer 16

Maintain ECM in adipose tissue

Question 17

What is the function of Osteoclasts?

Answer 17

Recycle (breakdown) the ECM in bone

Question 18

What is the function of osteoblasts and osteocytes?

Answer 18

Secrete and maintain mineralised ECM in the bone

Question 19

Why are connective tissues described as highly vascularised?

What are the exceptions?

Answer 19

• have lots of blood vessels and lymphatics going through tissue
• have immune cells, survey tissues for invading pathogens/cells damage

Exceptions - cartilage, tendons and ligaments

Question 20

Why is it difficult for cartilage, tendons and ligaments to repair?

Answer 20

Cartilage = no blood vessels

Tendons/ Ligaments= very few blood vessels

Question 21

What is dense connective tissue made up of?
Give 3 examples.

Answer 21

Mostly fibres

Regular
Irregular
Elastic

Question 22

What is loose connective tissue made up of?

3 examples

Answer 22

Mostly ground substance

Areolar
Adipose
Reticular

Question 23

What is connective tissues proper?

Answer 23

Category of diverse structure and functions

Loose or dense depending on arrangement of fibres

Question 24

What is areolar tissue and where is it found?

Answer 24

Universal packing material - supports and binds other tissues

Found beneath skin, submucosa and surrounding capillaries

Question 25

What can areolar tissue contain?

Answer 25

Collagen and elastin fibres Immune cells

Question 26

Functions of adipose tissue and where is it found?

Answer 26

Function: energy store, shock absorption, insulation Found deep beneath skin, breast, in abdomen, finger and foot pads Contains collagen fibres

Question 27

What is reticular connective tissue?

Answer 27

Delicate branched network (type 3 collagen) providing internal structure to highly cellular organs eg. Liver, lymph nodes, spleen.

Question 28

What is dense regular connective tissue?

Answer 28

Closely packed collagen fibres running in same direction

Question 29

What does dense regular connective tissue provide and where is it found?

Answer 29

Tensile strength and stability to joints Found in tendons and ligaments

Question 30

What is dense irregular connective tissue and what does it provide?

Answer 30

Closely packed interwoven fibres running in different directions Provides strength in different planes

Question 31

Where is dense irregular connective tissue found and what does it form?

Answer 31

Found in dermis of skin, forms protective capsule around organs

Question 32

What is elastic connective tissue?

Answer 32

Dense regular tissue dominated by elastic fibres

Question 33

What does elastic connective tissue allow and where is it found?

Answer 33

Allows tissues to recoil after stretching Found in arteries, skin, lungs, and underlying transitional epithelium Packed full of elastic fibres

Question 34

What causes scurvy and what does it lead too?

Answer 34

Lack of vitamin C Leading to defective collagen formation Loss of teeth, skin haemorrhages, death

Question 35

Who is likely to get scurvy and what is the treatment for it? Yea

Answer 35

Alcoholics, children, elderly (malnutrition) Treatment: citrus fruits, tomatoes, vit c supplements

Question 36

What is the structure of collagen and how does it arise?

Answer 36

Triple helix structure Arises from unusual abundance of 3 amino acids: Glycine Proline Hydroxyproline

Question 37

What would happen without collagens structural support?

Answer 37

Blood vessels, tendons and skin would become fragile.

Question 38

What happens if there is a lack of vit C in collagen chains?

Answer 38

Collagen chains aren’t sufficiently hydroxylated and they can’t fork alpha helix chains.

Question 39

Name 2 connective tissues disorders with oral manifestations?

Answer 39

Systemic lupus erythematosis Sjogren’s

Question 40

What is systemic lupus erythematosis?

Answer 40

Autoimmune disease - antibodies target host tissues

Question 41

Oral symptoms of systemic lupus erythematosis?

Answer 41

Dryness and soreness Oral manifestations include buccal and palatial lesions

Question 42

What tissues does systemic lupus erythematosis attack?

Answer 42

Skin Bones Tendons Kidneys Unnecessarily destroys them

Question 43

What is Sjogrens?

Answer 43

Autoimmune disease Autoantibodies affect glands that produce tears and saliva

Question 44

Symptoms of sjogrens?

Answer 44

Dry eyes and mouth Oral manifestations = increased dental caries and candidiasis (fungal disease)