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

1. Introduction to Anatomy & Physiology

Introduction to Organ Systems

Anatomy & Physiology

1. Introduction to Anatomy & Physiology

Introduction to Organ Systems

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Multiple Choice

At which vertebral level is a spinal tap (lumbar puncture) typically performed to avoid injury to the spinal cord?

Between L1 and L2 vertebrae

Between L3 and L4 vertebrae

Between T12 and L1 vertebrae

Between C7 and T1 vertebrae

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Verified step by step guidance

Understand the anatomy of the spinal cord: The spinal cord typically ends at the level of L1-L2 in adults, forming the conus medullaris. Below this level, the cauda equina (a bundle of nerve roots) occupies the vertebral canal, reducing the risk of spinal cord injury during a lumbar puncture.

Identify the purpose of a spinal tap: A lumbar puncture is performed to collect cerebrospinal fluid (CSF) for diagnostic purposes or to administer medications. It is crucial to avoid puncturing the spinal cord, which is why the procedure is done below its termination point.

Determine the safest vertebral level: The procedure is typically performed between the L3 and L4 vertebrae or sometimes between L4 and L5. These levels are below the termination of the spinal cord, ensuring safety.

Locate the anatomical landmarks: The L3-L4 interspace can be identified by palpating the iliac crests (the top of the hip bones) and drawing an imaginary horizontal line between them. This line usually intersects the L4 vertebra, helping to locate the appropriate site for the puncture.

Understand why other options are incorrect: Performing a spinal tap at levels such as T12-L1 or C7-T1 would risk injury to the spinal cord, as these levels are above its termination point. The L1-L2 level is also avoided because the spinal cord ends here, making it less safe than the L3-L4 level.