Question
A scientist is studying a new protist species that is a type of single-celled eukaryote. Using both microscope and biochemical techniques, they have determined the following movements across the cells membrane:
Biomolecule Movement #1:
Lactose moves through a channel protein in the membrane of the cell from a high concentration on the outside to a low concentration of lactose on the inside.
Biomolecule Movement #2:
Potassium is pumped out of the cell using a membrane protein from a low concentration of potassium on the inside of the cell to a high concentration of potassium on the outside of the cell.
Biomolecule Movement #3:
Oxygen gas moves from a high concentration on the outside of the cell to a low concentration inside the cell. The gas does not appear to need any membrane protein to cross the cell membrane.
Biomolecule Movement #4:
Water moves from a hypotonic environment on the outside of the cell to a hypertonic environment on the inside of the cell through protein channels called aquaporins.
Based on these conclusions, identify the movement of biomolecules that demonstrates both osmosis and facilitated diffusion across a cell membrane.
(1 point)
Responses
Biomolecule Movement #2
Biomolecule Movement #2
Biomolecule Movement #3
Biomolecule Movement #3
Biomolecule Movement #4
Biomolecule Movement #4
Biomolecule Movement #1
Biomolecule Movement #1
Remaining Attempts : 3
Skip to navigation
Biomolecule Movement #1:
Lactose moves through a channel protein in the membrane of the cell from a high concentration on the outside to a low concentration of lactose on the inside.
Biomolecule Movement #2:
Potassium is pumped out of the cell using a membrane protein from a low concentration of potassium on the inside of the cell to a high concentration of potassium on the outside of the cell.
Biomolecule Movement #3:
Oxygen gas moves from a high concentration on the outside of the cell to a low concentration inside the cell. The gas does not appear to need any membrane protein to cross the cell membrane.
Biomolecule Movement #4:
Water moves from a hypotonic environment on the outside of the cell to a hypertonic environment on the inside of the cell through protein channels called aquaporins.
Based on these conclusions, identify the movement of biomolecules that demonstrates both osmosis and facilitated diffusion across a cell membrane.
(1 point)
Responses
Biomolecule Movement #2
Biomolecule Movement #2
Biomolecule Movement #3
Biomolecule Movement #3
Biomolecule Movement #4
Biomolecule Movement #4
Biomolecule Movement #1
Biomolecule Movement #1
Remaining Attempts : 3
Skip to navigation
Answers
GPT-4o mini
To identify the movement of biomolecules that demonstrates both osmosis and facilitated diffusion across a cell membrane, let's review the definitions:
- **Osmosis** is the diffusion of water across a selectively permeable membrane from a region of lower solute concentration (hypotonic) to a region of higher solute concentration (hypertonic), and it often involves protein channels called aquaporins.
- **Facilitated diffusion** is the passive transport of molecules across a cell membrane via specific transmembrane proteins, from a region of high concentration to a region of low concentration.
Now, we can analyze the given movements:
1. **Movement #1 (Lactose)** - This is an example of facilitated diffusion because lactose moves through a channel protein from a high concentration outside to a low concentration inside.
2. **Movement #2 (Potassium)** - This describes active transport, as potassium is being pumped against its concentration gradient using energy (low to high concentration).
3. **Movement #3 (Oxygen)** - This is simple diffusion because oxygen gas moves directly across the membrane from high concentration to low concentration without the need for a membrane protein.
4. **Movement #4 (Water)** - This is an example of osmosis, as water is moving from a hypotonic environment outside to a hypertonic environment inside through aquaporins, demonstrating facilitated diffusion for water.
Based on this analysis, **Biomolecule Movement #4** (water moving through aquaporins) demonstrates osmosis, and it involves facilitated diffusion, as it requires protein channels (aquaporins) to facilitate the movement.
Thus, the correct answer is:
**Biomolecule Movement #4**
- **Osmosis** is the diffusion of water across a selectively permeable membrane from a region of lower solute concentration (hypotonic) to a region of higher solute concentration (hypertonic), and it often involves protein channels called aquaporins.
- **Facilitated diffusion** is the passive transport of molecules across a cell membrane via specific transmembrane proteins, from a region of high concentration to a region of low concentration.
Now, we can analyze the given movements:
1. **Movement #1 (Lactose)** - This is an example of facilitated diffusion because lactose moves through a channel protein from a high concentration outside to a low concentration inside.
2. **Movement #2 (Potassium)** - This describes active transport, as potassium is being pumped against its concentration gradient using energy (low to high concentration).
3. **Movement #3 (Oxygen)** - This is simple diffusion because oxygen gas moves directly across the membrane from high concentration to low concentration without the need for a membrane protein.
4. **Movement #4 (Water)** - This is an example of osmosis, as water is moving from a hypotonic environment outside to a hypertonic environment inside through aquaporins, demonstrating facilitated diffusion for water.
Based on this analysis, **Biomolecule Movement #4** (water moving through aquaporins) demonstrates osmosis, and it involves facilitated diffusion, as it requires protein channels (aquaporins) to facilitate the movement.
Thus, the correct answer is:
**Biomolecule Movement #4**