Inflammation and Repair Practice Questions

Q: Flare response in triple response occurs due to?

Vasodilation due to release of secondary mediators. The **Triple Response of Lewis** is a classic physiological reaction of the skin to mechanical injury, illustrating the vascular changes in acute inflammation. It consists of three distinct stages: 1. **Red Spot (Flush):** Localized vasodilation of capillaries and venules due to direct mechanical stimulation and histamine release. 2. **Flare (The correct answer):** A bright red, irregular area surrounding the red spot. This occurs due to **vasodilation of adjacent arterioles** mediated by an **axon reflex**. When the skin is injured, sensory nerve endings are stimulated, releasing **secondary mediators** (specifically Neuropeptides like Substance P and Calcitonin Gene-Related Peptide/CGRP), which cause widespread vasodilation [1]. 3. **Wheal:** Localized edema (swelling) caused by **increased vascular permeability** of post-capillary venules, leading to exudation of fluid. ### Why the other options are incorrect: * **Option B:** Chemotaxis and adhesion are cellular events of inflammation that occur later; they do not contribute to the immediate vascular "flare." * **Option C:** Direct vessel injury causes the initial "Red Spot," but the "Flare" is a neurogenic response extending beyond the site of direct trauma. * **Option D:** Increased vascular permeability is the mechanism behind the **Wheal** formation, not the Flare. ### NEET-PG High-Yield Pearls: * **Mediator of Triple Response:** Histamine is the primary chemical mediator involved. * **Axon Reflex:** The Flare is unique because it depends on an intact nerve supply (orthodromic and antidromic conduction). * **Sequence:** Red Spot (seconds) → Flare (30-60 seconds) → Wheal (1-5 minutes). **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, pp. 100-101.

Question 1

What types of cells are predominant in the early phase of inflammation?

Accepted Answer

Neutrophils

Answer

Macrophages

Answer

Basophils

Answer

Mast cells

Question 2

Which of the following factors does NOT inhibit wound healing?

Accepted Answer

Hyperthermia

Answer

Hypoxia

Answer

Hyperglycemia

Answer

Infection

Question 3

Which of the following occurs in chronic granulomatous disease?

Accepted Answer

Defective H2O2 production

Answer

Myeloperoxidase deficiency

Answer

Defective polymerization

Answer

Defective phagocytosis

Question 4

Formation of granulation tissue is due to?

Accepted Answer

Budding of new capillaries

Answer

Thrombosed vessels

Answer

Mucosal proliferation

Answer

Infiltration of cells

Question 5

Increased capillary permeability is caused by all of the following except?

Accepted Answer

Renin

Answer

Anaphylatoxin

Answer

5-hydroxytryptamine

Answer

Histamines

Question 6

Replacement of columnar epithelium of the respiratory tract by squamous epithelium is termed as?

Accepted Answer

Metaplasia

Answer

Hyperplasia

Answer

Hypoplasia

Answer

None of the above

Question 7

How many hours after injury are activated fibroblasts, myofibroblasts, and capillary sprouts most abundant in a wound?

Accepted Answer

3 to 5 days

Answer

3 to 6 hours

Answer

12 to 24 hours

Answer

8 to 10 days

Question 8

Flare response in triple response occurs due to?

Accepted Answer

Vasodilation due to release of secondary mediators

Answer

Chemotaxis and adhesion of leucocytes to the vessel wall

Answer

Direct vessel injury

Answer

Increased vascular permeability

Question 9

Delayed wound healing is seen in all EXCEPT:

Accepted Answer

Hypertension

Answer

Malignancy

Answer

Diabetes

Answer

Infection

Question 10

Nearly 20% of the normal tensile strength of tissue at the site of a wound is gained after how much time of wound healing?

Accepted Answer

3 weeks

Answer

1 week

Answer

2 weeks

Answer

4 weeks

Inflammation and Repair — MCQs

Inflammation and Repair — MCQs

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