A student is investigating cellular transport. She fills a beaker with 250 ml of water. She places 10 drops of red food coloring into the beaker of water and makes an observation immediately, after 5 minutes, and after 30 minutes. Her set up is shown below.
image 1d20ce72fe7f46398a49824621975558
The student observes that the molecules of red dye move from an area of higher concentration to an area of lower concentration until equilibrium is reached. Which best describes the type of cellular transport that the student is investigating?
a
The student is investigating the passive transport of diffusion.
b
The student is investigating the passive transport of osmosis.
c
The student is investigating the active transport of diffusion.
d
The student is investigating the active transport of osmosis.
b. The student is investigating the passive transport of osmosis.
a
The student is investigating the passive transport of diffusion.
To determine the type of cellular transport the student is investigating, let's first understand the terms mentioned.
Passive transport refers to the movement of substances across a cell membrane without the use of energy. This can occur through two processes: diffusion and osmosis.
- Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration until equilibrium is reached.
- Osmosis is the diffusion of water molecules across a selectively permeable membrane (such as a cell membrane) from an area of lower solute concentration to an area of higher solute concentration until equilibrium is reached.
On the other hand, active transport refers to the movement of substances across a cell membrane using energy (usually in the form of ATP) against the concentration gradient.
In the given scenario, the student observes that the molecules of red dye move from an area of higher concentration (where the food coloring drops were added) to an area of lower concentration (the rest of the water in the beaker), until equilibrium is reached. Thus, the student is investigating the passive transport of diffusion.
Therefore, the correct answer is:
a. The student is investigating the passive transport of diffusion.