Which phrase does NOT describe one of the functions of proteins of the plasma membrane?
-forming a channel through the membrane
-initiating the replication of the genetic material (CORRECT)
-binding to a substance to carry it through the membrane
-acting as a pump to move ions into and out of the cell.
-increasing the rate of a chemical reaction
The correct answered is marked above, but I am having a difficult time explaining why that is the correct answer compared to the others. Can someone please explain?
The correct answer is "initiating the replication of the genetic material" because proteins of the plasma membrane do not have this function. The other functions listed are all functions of proteins of the plasma membrane, such as forming a channel through the membrane, binding to a substance to carry it through the membrane, acting as a pump to move ions into and out of the cell, and increasing the rate of a chemical reaction.
The correct answer is "initiating the replication of the genetic material."
To understand why this phrase does not describe one of the functions of proteins in the plasma membrane, we need to first understand the functions of proteins in the plasma membrane.
Proteins in the plasma membrane have several important functions:
1. Forming a channel through the membrane: Many proteins in the plasma membrane are specialized to form channels or pores that allow the selective passage of ions, molecules, and other substances across the membrane.
2. Binding to a substance to carry it through the membrane: Certain proteins in the plasma membrane act as carriers or transporters, which bind to specific substances and facilitate their movement across the membrane.
3. Acting as a pump to move ions into and out of the cell: Some proteins in the plasma membrane, known as pumps or ion channels, actively transport ions across the membrane, creating concentration gradients that are important for various cellular processes.
4. Increasing the rate of a chemical reaction: Proteins in the plasma membrane can also function as enzymes, which accelerate specific chemical reactions, allowing them to occur at a much faster rate.
Now, coming back to the phrase "initiating the replication of the genetic material," it does not describe one of the functions of proteins in the plasma membrane because the replication of genetic material occurs within the nucleus (in eukaryotic cells) or the nucleoid region (in prokaryotic cells), not in the plasma membrane. Replication of genetic material involves the action of specific enzymes and does not directly involve proteins in the plasma membrane.
Therefore, based on the functions mentioned above, the phrase "initiating the replication of the genetic material" does not describe one of the functions of proteins in the plasma membrane.
The phrase that does not describe one of the functions of proteins of the plasma membrane is "initiating the replication of the genetic material."
Proteins in the plasma membrane have various roles and functions in the cell. Let's go through the descriptions of the other phrases to understand why they are all valid functions except for the one given:
- Forming a channel through the membrane: Many proteins in the plasma membrane act as channel proteins or ion channels. They create a pore or channel that allows specific substances (such as ions or molecules) to pass through the membrane.
- Binding to a substance to carry it through the membrane: Other proteins in the plasma membrane act as carrier proteins or transporters. They bind to specific substances, like glucose or amino acids, and facilitate their transport across the membrane.
- Acting as a pump to move ions into and out of the cell: Some proteins in the plasma membrane are involved in active transport, where they use cellular energy (such as ATP) to pump ions or molecules against their concentration gradient, either into or out of the cell.
- Increasing the rate of a chemical reaction: Enzymes are a type of protein that can increase the rate of chemical reactions. Proteins in the plasma membrane can function as enzymes, facilitating or catalyzing specific chemical reactions that occur at the membrane.
On the other hand, the function described in "initiating the replication of the genetic material" refers to a role specific to nucleic acids (DNA and RNA). Proteins are not directly involved in initiating DNA replication; rather, enzymes like DNA polymerase carry out the replication process. So, this statement does not describe one of the functions of proteins in the plasma membrane.