Inflammation, healing and repair

Question 1

Causes of cell injury

Answer 1

-Oxygen deprivation: reduced blood supply
-Chemical agents: pollutants
-Infectious agents: Bacteria, fungi, viruses
-Immunlogic reactions: Autoimmune reactions
-Genetic defects: Congenital deficiency in functional proteins. acquired accumluation of damaged DNA.
-Nutritional imbalance: Iron deficiency causing epithelial atrophy.
- Physical agents- physical harm, trauma, temperature, pressure
- Aging- diminished ability to respond to damage.

Question 2

Hypertrophy

Answer 2

Increase size of individual cells

Question 3

Hyperplasia

Answer 3

Increase in number of cells

Question 4

Atrophy

Answer 4

Decrease in the cell and organ size- by loss of cell substance

Question 5

Metaplasia

Answer 5

Change in the form of cells leading to a change in appearance of the tissue.

Question 6

Weight gain can lead to…

Answer 6

Hypertrophy- increase in size of cells
Hyperplasia- increase in number of cells

Question 7

Necrosis

Answer 7

Cell death after external stimuli
-cell contents leak out of the extracellular matrix and elicit inflammation.

Question 8

Apoptosis

Answer 8

Programmed cell death
No inflamation but other cells engulf fragments through phagocytes.

Question 9

Acute inflammation

Answer 9

Rapid onset
Neutrophils are brought in large numbers to the site of injury or infection to engulf all disease and debry material.
Dilution of blood cells at site of injury increasing the flow blood. its leaky so white blood cells can exit the leaky vessel wall to the injured site.

Question 10

Signs of inflammation

Answer 10

Heat- increased flow of blood
Pain
Redness- from increased red blood
Swelling
Loss of function

Question 11

Outcome of inflammation
Resolution-
Suppuration-
Repair and organisation-

Answer 11

Resolution- minimal tissue damage/ rapid eradication

Suppuration (pus)- usually follows infection- a mixture of live and dead neutrophils.

Repair and organisation- healing with scar formation- extensive damage

Question 12

Chronic inflammation
Healing-
Repair-

Answer 12

Inflammation of prolonged duration
-active inflammation by chronic inflammatory cells

Healing- replacement of the damaged tissue with the same cell type

Repair- replacement of the diseased tissue with fibrous scar tissue.

Question 13

Regeneration

Answer 13

Necrotic cells are replaced with cells of the same type.
For this to happen- nature of injury is important- remaining cells must be able to divide and collagen framework of the tissue is intact.

Question 14

Types of cells- PICTURE

Answer 14

Labile
Stable
Permanent

Question 15

Types of cells- PICTURE

Answer 15

.

Question 16

Healing of bone

Answer 16

Osteoclasts- demolition bone
Osteoblasts- form bone
Remodelling- woven bone replaced by lamellar bone.