Connective And Adipose Tissue

Question 1

What are mast cells coated with?

Answer 1

Mast cells become coated with Immunoglobin E (IgE) - molecules which specifically bind allergens.

When an allergen cross-links these surface-bound IgE molecules, the contents of the granules are rapidly released from the cell.

Can result in immediate hypersensitivity reactions, allergy and anaphylaxis.

Question 2

What are the different fibres in connective tissue?

Answer 2

Collagen: flexible with high tensile strength
Reticular: Provide a support framework/sponge
Elastin: Allows tissues to recoil after stretch or distension

Question 3

Which type of collagen has fibrils that aggregate into fibres and fibre bundles (e.g. in tendons, capsules of organs and skin dermis)?

Answer 3

Type 1 collagen

The most widely distributed type (90% of all collagen)

Question 4

Which type of collagen is present in hyaline and elastic cartilage where the fibrils do not form fibres?

Answer 4

Type 2 collagen

Question 5

Which collagen type is found forming fibres around muscle and nerve cells and within lymphatic tissues and organs? It is called reticulin.

Answer 5

Type 3 collagen

Question 6

Which collagen type is unique and is present in basal lamina of basement membrane?

Answer 6

Type 4 collagen

Question 7

Type 1 collagen is composed of a triple helix of which type of chain:
A) alpha chains
B) beta chains

Answer 7

A) alpha chains

Question 8

Which vitamin is required for the intracellular production of procollagen?

Answer 8

Vitamin C.

Vitamin C deficiency leads to scurvy which includes poor wound healing and impaired bone formation.

Question 9

Osteogenesis imperfecta is caused by abnormal:
A. Type 2 collagen
B. Type 1 collagen
C. Type 3 collagen

Answer 9

B. Type 1 collagen

Question 10

Reticular fibres consist of which type of collagen?

Answer 10

Type 3

Question 11

What is the primary component of elastic fibres?

Answer 11

Elastin.
But itself enfolds and is surrounded by microfibrils called fibrillin.
It occurs in most connective tissues but to widely varying degrees.

Question 12

What places in the body do elastic fibres have an important role?

Answer 12

Dermis
Artery walls
Lungs
Those sites bearing elastic cartilage.

Question 13

Is Marfans syndrome autosomal dominant or autosomal recessive?

Answer 13

Autosomal dominant.

Question 14

What is the role of adipose tissue?

Answer 14

Contains fat- a fuel reserve
Thermal insulation
Shock absorption

Question 15

What type of fat cells are there?

Answer 15

White and brown.

Question 16

Why are brown fat cells brown?

Answer 16

They contain a rich vascular supply and abundant mitochondria.

Question 17

Where would you find brown fat cells?

Answer 17

Close to the scapula, sternum and axillae (especially in newborns).
Also present in the upper chest and neck of adults.

Question 18

When you eat a meal what is secreted by fat cells?

Answer 18

Leptin (the appetite suppressor)
When you eat a meal, lepton is released from fat cells and sends signals to your brain to let you know you’re full and to stop eating.

Question 19

What stimulates your appetite and where is it released?

Answer 19

Gherlin. It is realeased in the stomach, and when elevated sends signals to your brain letting you know you’re hungry and it is time to heat.
Age, gender, blood glucose, and leptin levels all affect gherlin levels.