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 Adaptive Immunity

Anatomy & Physiology

21. The Immune System

Introduction to Adaptive Immunity

Previous problemNext problem

Struggling with Anatomy & Physiology?

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

Which of the following pathogens undergoes antigenic variation to avoid immune defenses?

Streptococcus pneumoniae

Escherichia coli

Mycobacterium tuberculosis

Influenza virus

Previous problemNext problem

Verified step by step guidance

Understand the concept of antigenic variation: Antigenic variation is a mechanism used by certain pathogens to alter their surface proteins, allowing them to evade the host's immune system. This process helps the pathogen avoid detection and destruction by immune cells.

Identify pathogens known for antigenic variation: Some pathogens are well-known for their ability to undergo antigenic variation. These include viruses like the Influenza virus, which frequently changes its surface antigens, making it difficult for the immune system to recognize and respond effectively.

Consider the characteristics of each pathogen listed: Streptococcus pneumoniae, Escherichia coli, and Mycobacterium tuberculosis are bacteria, while the Influenza virus is a virus. Among these, the Influenza virus is renowned for its antigenic variation capabilities.

Review the immune evasion strategies of the Influenza virus: The Influenza virus undergoes frequent changes in its hemagglutinin and neuraminidase proteins, which are key antigens recognized by the immune system. This antigenic shift and drift are responsible for the virus's ability to cause seasonal flu outbreaks and pandemics.

Conclude with the identification of the correct pathogen: Based on the understanding of antigenic variation and the characteristics of the listed pathogens, the Influenza virus is the correct answer as it is known for undergoing antigenic variation to avoid immune defenses.