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

2. Cell Chemistry & Cell Components

Simple and Facilitated Diffusion

Anatomy & Physiology

2. Cell Chemistry & Cell Components

Simple and Facilitated Diffusion

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Multiple Choice

Which of the following does not accurately describe a channel or a carrier?

Channel – open to both sides of the membrane simultaneously.

Carrier – open to one side of the membrane at a time.

Carrier – requires a conformation change to complete function.

Channel – not selective for molecules that move through it.

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Verified step by step guidance

Understand the basic function of channels and carriers in cell membranes. Channels are protein structures that allow specific molecules or ions to pass through the membrane, while carriers are proteins that transport substances across the membrane by changing shape.

Recognize that channels are typically selective, meaning they allow only certain molecules or ions to pass through based on size, charge, or other properties. This selectivity is crucial for maintaining cellular homeostasis.

Identify that carriers operate differently from channels. Carriers bind to a specific molecule on one side of the membrane, undergo a conformational change, and release the molecule on the other side. This process is often selective and can be active (requiring energy) or passive.

Evaluate the statement 'Channel – not selective for molecules that move through it.' Given the understanding that channels are generally selective, this statement does not accurately describe a typical channel.

Conclude that the statement 'Channel – not selective for molecules that move through it' is incorrect because it contradicts the fundamental characteristic of channels being selective for specific molecules or ions.