Which of the following statements about diffusion is false?
A In diffusion, molecules move from areas of greater concentration to areas of lesser concentration.
B Diffusion is a random process.
C Diffusion depends on the intrinsic kinetic energy of molecules.
D Diffusion continues until the concentrations are in equilibrium.
E Simple diffusion depends upon specific carrier proteins.
The correct answer and explanation is :
The correct answer is E: Simple diffusion depends upon specific carrier proteins.
Explanation:
Diffusion is the process by which molecules move from areas of higher concentration to areas of lower concentration. This movement is driven by the concentration gradient, and the process continues until equilibrium is reached (i.e., when the concentration of the molecules is the same throughout the space). Now, let’s examine each statement:
- A: In diffusion, molecules move from areas of greater concentration to areas of lesser concentration.
This is true. Diffusion naturally occurs due to the concentration gradient, where molecules tend to move from areas of higher concentration to areas of lower concentration until they are evenly distributed. - B: Diffusion is a random process.
This is also true. Diffusion is driven by the random motion of molecules. Molecules constantly move and collide with each other, which results in their tendency to spread out in the available space, leading to the diffusion process. - C: Diffusion depends on the intrinsic kinetic energy of molecules.
This is true. The movement of molecules in diffusion is driven by their intrinsic kinetic energy. Molecules are constantly in motion, and this motion helps them spread from areas of high concentration to areas of low concentration. - D: Diffusion continues until the concentrations are in equilibrium.
This is true. Diffusion generally continues until equilibrium is reached. At equilibrium, there is no net movement of molecules, as the concentration of molecules is the same throughout the space. - E: Simple diffusion depends upon specific carrier proteins.
This is false. Simple diffusion does not require the assistance of carrier proteins. Simple diffusion is a passive process where molecules, such as gases or small nonpolar molecules, move directly across the lipid bilayer of the cell membrane. In contrast, facilitated diffusion, which also involves passive transport, does require specific carrier proteins or channels to help larger or polar molecules move across the membrane.
Conclusion:
Simple diffusion is a passive process that does not require carrier proteins. It relies on the random motion of molecules and occurs until equilibrium is reached, based solely on the concentration gradient and the kinetic energy of the molecules.