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

Which of the following correctly lists the layers of the stomach wall from innermost to outermost?

Muscularis externa, mucosa, submucosa, serosa

Serosa, muscularis externa, submucosa, mucosa

Submucosa, mucosa, serosa, muscularis externa

Mucosa, submucosa, muscularis externa, serosa

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Verified step by step guidance

Step 1: Understand the structure of the stomach wall. The stomach wall is composed of four main layers, each with distinct functions and characteristics. These layers are organized from the innermost to the outermost as follows: mucosa, submucosa, muscularis externa, and serosa.

Step 2: Begin with the innermost layer, the mucosa. This layer is responsible for secretion (enzymes, mucus, and gastric acid) and absorption. It consists of three sublayers: the epithelium, lamina propria, and muscularis mucosae.

Step 3: Next is the submucosa, which lies directly beneath the mucosa. This layer contains connective tissue, blood vessels, lymphatics, and nerves. It provides support and nourishment to the mucosa.

Step 4: The muscularis externa is the third layer. It is composed of smooth muscle arranged in three layers (oblique, circular, and longitudinal) that help churn and mix food with gastric secretions, aiding in mechanical digestion.

Step 5: The outermost layer is the serosa. This is a thin layer of connective tissue covered by a simple squamous epithelium (mesothelium). It reduces friction between the stomach and surrounding organs by secreting serous fluid.