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

Introduction to Membrane Transport

Anatomy & Physiology

2. Cell Chemistry & Cell Components

Introduction to Membrane Transport

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

Which of the following best explains why a glucose transporter is required to move glucose into the cell?

Glucose is a large, polar molecule that cannot easily cross the lipid bilayer without assistance.

Glucose is actively pumped out of the cell by the sodium-potassium pump.

Glucose is a small, nonpolar molecule that diffuses freely through the membrane.

Glucose dissolves in the lipid bilayer and enters the cell by simple diffusion.

Previous problemNext problem

Verified step by step guidance

Step 1: Understand the structure of the cell membrane. The cell membrane is composed of a phospholipid bilayer, which has hydrophobic (water-repelling) tails and hydrophilic (water-attracting) heads. This structure makes it selectively permeable to certain molecules.

Step 2: Analyze the properties of glucose. Glucose is a large, polar molecule, meaning it has an uneven distribution of electrical charge. Polar molecules generally cannot pass through the hydrophobic core of the lipid bilayer without assistance.

Step 3: Recognize the role of transport proteins. Transport proteins, such as glucose transporters, are embedded in the cell membrane and facilitate the movement of molecules that cannot diffuse freely through the lipid bilayer. These proteins provide a pathway for glucose to enter the cell.

Step 4: Eliminate incorrect options. For example, glucose is not actively pumped out of the cell by the sodium-potassium pump, as this pump specifically moves sodium and potassium ions. Additionally, glucose does not dissolve in the lipid bilayer or enter by simple diffusion because it is polar and large.

Step 5: Conclude that a glucose transporter is required because glucose is a large, polar molecule that cannot easily cross the lipid bilayer without assistance. This explains why facilitated diffusion is necessary for glucose transport into the cell.