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

15. The Special Senses

Introduction to Special Senses

Anatomy & Physiology

15. The Special Senses

Introduction to Special Senses

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Multiple Choice

Which structure controls the size of the pupil?

Retina

Iris

Lens

Cornea

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Verified step by step guidance

Understand the function of the pupil: The pupil is the opening in the center of the iris that allows light to enter the eye.

Identify the role of the iris: The iris is the colored part of the eye surrounding the pupil. It controls the size of the pupil by contracting or dilating in response to light intensity.

Differentiate the structures: The retina is responsible for receiving light and converting it into neural signals. The lens focuses light onto the retina. The cornea is the eye's outermost layer that helps focus incoming light.

Recognize the mechanism: The iris contains muscles that adjust the pupil size. In bright light, the iris contracts to make the pupil smaller, reducing light entry. In dim light, it dilates to allow more light in.

Conclude the correct structure: Based on the functions, the iris is the structure that directly controls the size of the pupil.