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

13. The Peripheral Nervous System

Reflex Arcs

Anatomy & Physiology

13. The Peripheral Nervous System

Reflex Arcs

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 ligament of the knee initiates the knee-jerk reflex when tapped?

Medial collateral ligament

Patellar ligament

Anterior cruciate ligament

Posterior cruciate ligament

Previous problemNext problem

Verified step by step guidance

Step 1: Understand the knee-jerk reflex. The knee-jerk reflex, also known as the patellar reflex, is a stretch reflex that occurs when the patellar ligament is tapped. This reflex tests the integrity of the nervous system, specifically the L2-L4 spinal segments.

Step 2: Identify the patellar ligament. The patellar ligament connects the patella (kneecap) to the tibial tuberosity of the tibia. It plays a key role in transmitting the force generated by the quadriceps muscle group during knee extension.

Step 3: Recognize the mechanism of the reflex. When the patellar ligament is tapped, it stretches the quadriceps tendon and muscle, activating muscle spindle receptors. These receptors send signals to the spinal cord, triggering a reflex contraction of the quadriceps muscle.

Step 4: Differentiate the patellar ligament from other knee ligaments. The medial collateral ligament, anterior cruciate ligament, and posterior cruciate ligament are involved in stabilizing the knee joint but are not directly involved in the knee-jerk reflex.

Step 5: Conclude that the patellar ligament is the correct answer because it is the structure tapped to initiate the knee-jerk reflex.