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 Directional Terms

Anatomy & Physiology

1. Introduction to Anatomy & Physiology

Introduction to Directional Terms

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Multiple Choice

Infoldings of the sarcolemma, called transverse (T) tubules, serve which of the following functions in muscle fibers?

Synthesize ATP for muscle energy

Transmit action potentials deep into the muscle fiber

Anchor myofibrils to the sarcolemma

Store calcium ions for muscle contraction

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Verified step by step guidance

Understand the structure and function of the sarcolemma: The sarcolemma is the plasma membrane of a muscle fiber. It plays a critical role in conducting electrical signals (action potentials) and maintaining the integrity of the muscle cell.

Learn about transverse (T) tubules: T tubules are invaginations of the sarcolemma that penetrate deep into the muscle fiber. They are essential for transmitting electrical signals to the interior of the muscle cell.

Explore the role of T tubules in action potential transmission: When an action potential is generated at the sarcolemma, it travels along the membrane and enters the T tubules. This ensures that the electrical signal reaches all parts of the muscle fiber, including the interior, for coordinated contraction.

Clarify why T tubules do not synthesize ATP or store calcium: ATP synthesis occurs in mitochondria, not T tubules. Calcium ions are stored in the sarcoplasmic reticulum, a specialized organelle within muscle cells, not in the T tubules.

Conclude the function of T tubules: The primary function of T tubules is to transmit action potentials deep into the muscle fiber, enabling the activation of the sarcoplasmic reticulum to release calcium ions for muscle contraction.