Connective tissues

Question 1

What are the 4 types of tissue?

Answer 1

Epithelium, connective, nervous, muscle

Question 2

Function of connective tissue

Answer 2

provide structure and function to organs and other tissues

Question 3

Connective tissues in the head of femur

Answer 3

articular cartilage, periosteum, cortical/compact bone, spongy/trabecular bone, fatty marrow (adipose)

Question 4

How does the structure of tendons reflect their function?

Answer 4

Dense, fibres run in parallel. High tensile strength to transfer force of muscle contraction to bone.

Question 5

Structure of a kidney tubule

Answer 5

Simple cuboidal epithelium resting on a basement membrane (CT composed of collagen fibres)

Question 6

3 main components of connective tissue

Answer 6

Ground substance, fibres, cells

Question 7

What do the fibres and ground substance form?

Answer 7

Extracellular matrix

Question 8

Functions of ground substance

Answer 8

Provides structural and biochemical support, water-binding ability (tissue volume) and supports intercellular exchange of substances via diffusion.

Question 9

What is ground substance composed of?

Answer 9

Glycoproteins and complex carbohydrates (e.g. hyaluronic acid, glucosamine) - forms clear, semi-solid gel

Question 10

Function of fibres

Answer 10

Provide tensile strength and structural integrity (supporting framework for ground substance and cells)

Question 11

2 main types of fibres

Answer 11

collagen and elastin

Question 12

How does the structure of elastin relate to its function?

Answer 12

Fibres are long and branched which provide stretch and recoil ability.

Question 13

Which cells synthesise and secrete collagen and elastin into the ECM?

Answer 13

Fibroblasts

Question 14

Where is type I collagen found?

Answer 14

Fibrous tissues (dermis of skin, tendons, ligaments, bone)

Question 15

Where is type II collagen found?

Answer 15

Hyaline cartilage

Question 16

Structure and location of type III collagen?

Answer 16

Delicate branched ‘reticular’ network found in highly cellular organs (liver, lymph nodes)

Question 17

Which organs is elastin found in?

Answer 17

Blood vessels, skin, bladder, lungs

Question 17

Function of connective tissue cells

Answer 17

to synthesise, secrete, recycle ECM (ground substance and fibres)

Question 17

What suffix is given to cells that synthesise and secrete the ECM?

Answer 17

-blasts

Question 18

What suffix is given to cells that maintain the ECM?

Answer 18

-cytes

Question 19

What suffix is given to cells that recycle/breakdown the ECM?

Answer 19

-clasts

Question 20

Function of odontoblasts

Answer 20

Synthesise dentin in teeth

Question 21

Highly vascularised meaning

Answer 21

Contain lots of blood vessels and lymph vessels therefore immune cells are present.

Question 22

All connective tissue is highly vascularised except:

Answer 22

cartilage, tendons and ligaments (very few)

Question 23

Consequence of not being vascularised

Answer 23

Tissue cannot repair itself / very slow

Question 24

3 classification classes of connective tissues

Answer 24

- connective tissue proper - skeletal connective tissue (cartilage, bone) - fluid connective tissue (blood, lymph)

Question 25

How is connective tissue proper subdivided?

Answer 25

Loose (few fibres, more ground substance) and dense (more fibres, less ground substance)

Question 26

What is areolar tissue?

Answer 26

Loose arrangement of collagen and/or elastin fibres. Packing material - supports and binds other tissues

Question 27

Location of areolar tissue

Answer 27

beneath skin, submucosa, surrounding capillaries

Question 28

structure of adipose tissue

Answer 28

loose connective tissue made of adipocytes found in isolation or in clusters throughout fibrous CT. Adipocytes hold lipid droplet in centre of cell (lipid removed in tissue preparation)

Question 29

Function of adipose tissue

Answer 29

energy storage, shock absorption, insulation

Question 30

Location of adipose tissue

Answer 30

deep layers of dermis, breasts, abdomen, hand and foot pads.

Question 31

Structure of reticular tissue

Answer 31

Loose arrangement of delicately branched (type III) collagen fibres

Question 32

Function of reticular tissue

Answer 32

Supporting network to highly cellular organs (liver, lymph nodes, spleen - e.g. creates a fine scaffold to support hepatocytes)

Question 33

3 examples of loose connective tissue proper

Answer 33

Areolar, adipose, reticular tissue

Question 34

3 examples of dense connective tissue proper

Answer 34

Dense regular, dense irregular, elastic tissue

Question 35

Structure and function of dense regular tissue?

Answer 35

Dense arrangement of collagen fibres running in same direction. Provides tensile strength.

Question 36

Where is dense regular tissue found?

Answer 36

tendons and ligaments

Question 37

Structure and function of dense irregular tissue

Answer 37

Dense arrangement of collagen and elastin fibres in random orientation. Provides strength, stretch and recoil in multiple directions.

Question 38

Where is dense irregular tissue found?

Answer 38

dermis of skin, protective capsule around organs

Question 39

Structure and function of elastic tissue

Answer 39

Dense arrangement of elastic and collagen fibres. Allows stretch and recoil of tissues.

Question 40

Where is elastic tissue found?

Answer 40

arteries, lungs, under transitional epithelium in the bladder

Question 41

Cause of scurvy

Answer 41

lack of vitamin C

Question 42

Effects of scurvy

Answer 42

defective collagen formation - loose teeth/periodontitis, skin haemorrhages/poor wound healing, weakness, anaemia

Question 43

Treatment of scurvy

Answer 43

Vit C supplements, high vit C diet (tomatoes, citrus fruits)

Question 44

The triple-helical structure of collagen arises from the unusual abundance of which 3 amino acids?

Answer 44

Glycine, proline, hydroxyproline

Question 45

How does vit C affect collagen synthesis?

Answer 45

Vit C is a co-factor for hydroxylase enzymes which catalyse the addition of OH to proline to form hydroxyproline. In vit C deficient cells, collagen is insufficiently hydroxylated so alpha-helix chains can't form.

Question 46

What is Systemic Lupus Erythematosis (SLE)?

Answer 46

Autoimmune disease targeting skin, bones, tendons and kidneys

Question 47

What are autoantibodies?

Answer 47

Antibodies that incorrectly target host cells (autoimmune)

Question 48

Head and neck symptoms of lupus

Answer 48

Oral: dryness, soreness, buccal and palatal lesions. Butterfly erythema - redness across cheeks and nose.

Question 49

What is Sjogren's?

Answer 49

Autoimmune disease - antibodies target tear and salivary glands.

Question 50

Symptoms of Sjogren's

Answer 50

dry eyes and mouth. increased dental caries and candidiasis (less saliva -> fewer antimicrobial proteins -> more fungi/bacteria)