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

9. Muscle Tissue

Sliding Filament Theory and the Sacromere

Anatomy & Physiology

9. Muscle Tissue

Sliding Filament Theory and the Sacromere

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

In the context of the sliding filament theory, which structure releases calcium into the sarcoplasm to initiate muscle contraction?

Mitochondria

Nucleus

Sarcoplasmic reticulum

Golgi apparatus

Previous problemNext problem

Verified step by step guidance

Understand the sliding filament theory: This theory explains how muscles contract by the sliding of actin and myosin filaments past each other, which shortens the muscle fiber.

Identify the role of calcium ions: Calcium ions are crucial for muscle contraction as they bind to troponin, causing a conformational change that moves tropomyosin away from the binding sites on actin filaments, allowing myosin heads to attach to actin.

Recognize the source of calcium ions: In muscle cells, the sarcoplasmic reticulum is the specialized endoplasmic reticulum that stores calcium ions.

Learn the process of calcium release: When a muscle cell is stimulated by a nerve impulse, the sarcoplasmic reticulum releases calcium ions into the sarcoplasm (the cytoplasm of muscle cells).

Connect the structure to the function: The sarcoplasmic reticulum's release of calcium into the sarcoplasm is the key event that initiates muscle contraction according to the sliding filament theory.