Table of contents

1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart3h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

21. The Immune System

Introduction to Innate Immunity

Anatomy & Physiology

21. The Immune System

Introduction to Innate Immunity

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Multiple Choice

What is the primary reason for administering an epinephrine auto-injector during a life-threatening allergic reaction?

To rapidly reverse airway constriction and improve breathing

To neutralize the allergen in the bloodstream

To slow down the heart rate

To increase the production of antibodies

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Verified step by step guidance

Understand the physiological effects of epinephrine: Epinephrine is a hormone and neurotransmitter that acts on the body's adrenergic receptors. It primarily stimulates alpha and beta receptors, leading to effects such as bronchodilation (opening of airways), vasoconstriction (narrowing of blood vessels), and increased heart rate.

Identify the symptoms of a life-threatening allergic reaction: Severe allergic reactions, known as anaphylaxis, often involve airway constriction, swelling, and difficulty breathing. These symptoms are caused by the release of histamine and other inflammatory mediators during the allergic response.

Determine the mechanism of action of epinephrine in anaphylaxis: Epinephrine works by relaxing the smooth muscles in the airways (via beta-2 adrenergic receptors), reducing airway constriction, and improving breathing. It also counteracts the effects of histamine by causing vasoconstriction, which reduces swelling and prevents a dangerous drop in blood pressure.

Evaluate the incorrect options: Neutralizing the allergen in the bloodstream is not the role of epinephrine; this would require immune system intervention. Slowing down the heart rate is incorrect because epinephrine typically increases heart rate. Increasing antibody production is also incorrect, as epinephrine does not directly affect the immune system's production of antibodies.

Conclude the primary reason for administering an epinephrine auto-injector: The main purpose is to rapidly reverse airway constriction and improve breathing during anaphylaxis, which is critical for preventing suffocation and stabilizing the patient.