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

What is Anatomy & Physiology?

Anatomy & Physiology

1. Introduction to Anatomy & Physiology

What is Anatomy & Physiology?

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Multiple Choice

Which type of lever is the most common in the human body?

Third class lever

First class lever

Second class lever

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Verified step by step guidance

Understand the concept of levers: A lever is a rigid structure (like a bone) that rotates around a fixed point called the fulcrum. In the human body, levers are formed by bones, joints (fulcrums), and muscles (force).

Learn the three types of levers: First-class levers have the fulcrum between the effort and the load (e.g., nodding the head). Second-class levers have the load between the fulcrum and the effort (e.g., standing on tiptoes). Third-class levers have the effort between the fulcrum and the load (e.g., biceps lifting the forearm).

Recognize that third-class levers are the most common in the human body. They allow for greater speed and range of motion, which is essential for many movements like flexing the elbow or lifting objects.

Analyze examples of third-class levers in the body: For instance, when the biceps muscle contracts to lift the forearm, the elbow joint acts as the fulcrum, the biceps provide the effort, and the forearm and hand represent the load.

Conclude that third-class levers are the most prevalent type in the human body because they prioritize movement efficiency and speed over force, which aligns with the functional needs of the musculoskeletal system.