Connective Tissue

Question 1

What is the extracellular matrix made up of?

Answer 1

Ground substance and fibres

Question 2

What is the ground substance made of?

Answer 2

Hyaluronate proteoglycan aggregates

Question 3

What kind of fibres can there be?

Answer 3

Collagen, reticular or elastic

Question 4

Name the specialised types of connective tissue

Answer 4

adipose tissue, blood, cartilage, bone, lymphatic tissue and haemopoietic tissue

Question 5

What kind of cells make up cartilage?

Answer 5

Chondrocytes

Question 6

What kind of cells make up ligaments and tendons?

Answer 6

Fibroblasts

Question 7

What cells form skeletal muscle?

Answer 7

Myoblasts

Question 8

What is the embryonic origin of all the connective tissue?

Answer 8

Mesenchyme

Question 9

What are the features of the mesenchyme?

Answer 9

tapering appearance to cells and abundant viscous ground substance

Question 10

What is the mucous connective tissue in an embryo called?

Answer 10

Wharton’s jelly - from the umbilical cord

Question 11

What does a proteoglycan monomer consist of?

Answer 11

A core protein of approximately 100 GAG units

GAG = glycosaminoglycan

Question 12

What do proteoglycan form linear aggregates with?

Answer 12

Hyaluronic acid and collagen fibrils

Question 13

What is the charge on GAGs and why is this good?

Answer 13

Negative charge

Attracts water so that a hydrated gel is formed

Question 14

Which type of collagen is present in cartilage?

Answer 14

Type II

Question 15

What is the other name for type III collagen?

Answer 15

Reticulin

Question 16

What are the features of Type I collagen?

Answer 16

periodic banding, fibrils composed of staggered collagen molecules, triple helix of alpha chains and every third amino acid is glycine

Question 17

What is Marfan’s syndrome?

Answer 17

Autosomal dominant disorder. Expression of the Fibrillin gene is abnormal so elastic tissue is abnormal. Sufferers are abnormally tall, exhibit arachnodactyly (long fingers and toes) and have frequent joint dislocation.

Question 18

What are the 3 layers of a small elastic artery in order from inside to outside?

Answer 18

tunica intima: endothelial cells
tunica media: elastin lamellae
tunica adventitia: collagen

Question 19

What do myotendinous junctions consist of?

Answer 19

Skeletal muscle fibres interdigitate with tendon collagen bundles

Question 20

What does ligament join together?

Answer 20

Bone to bone

Question 21

How is ligament arranged?

Answer 21

Into fascicles separated by loose connective tissue

Question 22

What 2 cellular features will fibroblasts have?

Answer 22

Lots of RER and Lots of euchromatin

Question 23

Which cells are primarily responsible for the formation of scar tissue?

Answer 23

Fibroblasts

Question 24

Which cells are professional antigen presenting cells?

Answer 24

Macrophages

Question 25

What substances do the granules in mast cells contain?

Answer 25

Heparin, Histamine and Cytokines

Question 26

What is heparin?

Answer 26

An anticoagulant

Question 27

What is the function of histamine?

Answer 27

To increase blood vessel permeability

Question 28

What happens when allergens bind to mast cells?

Answer 28

The contents of the granules are rapidly released.

Question 29

What are the functions of adipose tissue?

Answer 29

fuel reserve, thermal insulation and shock absorption

Question 30

Why is brown adipose tissue brown?

Answer 30

Due to the rich vascular supply and abundant mitochondria

Question 31

Name some places where cartilage is found

Answer 31

embryonic skeleton, ends of long bones, nose, trachea and larynx

Question 32

What are the 3 major types of cartilage?

Answer 32

elastic, hyaline and fibrocartilage

Question 33

Is cartilage vascularised?

Answer 33

No | It is an avascular tissue.

Question 34

What is in the matrix of hyaline cartilage?

Answer 34

proteoglycans, hyaluronic acid and Type II collagen

Question 35

What is found in the matrix of elastic cartilage?

Answer 35

proteoglycans, hyaluronic acid, Type II collagen and elastic fibres

Question 36

What is the matrix of fibrocartilage made of?

Answer 36

proteoglycans, hyaluronic acid, Type II collagen and Type I collagen

Question 37

Which type of cartilage is the precursor to bone?

Answer 37

Hyaline

Question 38

Where is hyaline cartilage found?

Answer 38

parts of rib cage, nose, trachea, bronchi and larynx

Question 39

What cells are in the perichondrium?

Answer 39

Fibroblasts (outer) | which can develop into chondroblasts (inner)

Question 40

Why does the matrix stain darker around the chondrocytes?

Answer 40

The territorial matrix is more highly sulphated.

Question 41

What kinds of signals affect the synthetic activity of the chondrocytes?

Answer 41

mechanical, electrical and chemical

Question 42

What is different about elastic cartilage?

Answer 42

It does not calcify with age

Question 43

Where would you find elastic cartilage?

Answer 43

pinna of ear, initial canal of ear, epiglottis and Eustachian tube

Question 44

What are the features of fibrocartilage?

Answer 44

contains chondrocytes and fibroblasts, cells often distributed in rows and no perichondrium

Question 45

Where would you find fibrocartilage?

Answer 45

Intervertebral discs, Sternoclavicular joint, Temporomandibular joint, Menisci of knee and Pubic symphysis

Question 46

What are entheses?

Answer 46

Points of attachment of tendon and bone.

Question 47

What is the structure of cancellous bone?

Answer 47

A network of fine, bony columns or plates. The spaces between them are filled with bone marrow.

Question 48

Describe the placement of Haversian and Volkmann's canals

Answer 48

Haversian - the centre of every osteon Volkmann's - perpendicular to the Haversian canals

Question 49

How can you tell that bone is mature?

Answer 49

The osteocytes are arranged in concentric lamellae.

Question 50

Which direction do resorption canals run?

Answer 50

Parallel to osteons' long axes and Haversian canals

Question 51

What are the 2 ways of viewing bone?

Answer 51

decalcify mature bone so it can be sectioned or grind bone down to a thin layer

Question 52

How do osteoclasts break down bone?

Answer 52

They release H+ ions and lysosomal enzymes.

Question 53

What is the sequence of healing for a long bone?

Answer 53

haematoma formation, granulation tissue forms a soft procallus, procallus is replaced with a harder fibrocartilaginous callus, bony trabeculae develop, ossification occurs then remodelling occurs

Question 54

Define autograft

Answer 54

The donor of the bone is the recipient

Question 55

Define homograft

Answer 55

The donor of the bone is another human

Question 56

Define heterograft

Answer 56

The donor of the bone is a different species

Question 57

What are the connective tissue functions?

Answer 57

provide substance and form to the body and organs provide a medium for diffusion of nutrients and waste attach muscle to bone and bone to bone provide a cushion between tissues and organs defend against infection aid in injury repair