Answer:
A geneticist has devised a strategy to study protein translocation into the endoplasmic reticulum (ER) in yeast cells. She is interested in two different signal sequences that are thought to operate via slightly different translocation mechanisms. Using genetic engineering, she has fused the first signal sequence to a protein whose cytosolic expression is absolutely necessary for cell survival in the selective medium, but is inactive when in the ER. In the same cell, she has also fused the second signal sequence to a toxic protein whose cytosolic expression leads to cell lysis but is harmless when in the ER. Whereas wild-type cells undergo lysis upon the expression of these fusion proteins, she has been able to identify viable mutants, each of which has a loss-of-function mutation in a gene encoding a protein involved in membrane translocation. The products of these genes are probably ...
Explanation:
Involved in the transport of proteins with the first signal sequence but not the second one.
Answer: In an ionic bond the valence electrons are transferred from the metal only to the neighboring nonmetal, but in metallic bonding the valence electrons of each atom/ion are free to move or float around within the entire metal solid.
Explanation:
To know what type of transport occurred the lab and collected data are needed. As they are not present an explanation of the different transport's types, will be given.
Water, proteins, ions, and molecules of different sizes can pass through the cell membrane using different types of transports. The transport that each molecule uses depends on the concentration, size, and polarity.
We can classify the types of transport as active and passive.
Passive transport is the one that does not need energy to happen since the molecules move from a place of high concentration to a one of lower concentration. In this group, we have:
- Simple diffusion: small molecules in high concentration on one side of the membrane; move to the other side due to the difference in concentration.
- Osmosis: water passes through the membrane from a place of low concentration of molecules to one of high concentration. Water moves inside or outside the cell to valance the concentration of solutes on both sides of the membrane.
- Facilitated diffusion: uses proteins to transport large molecules, ions, or hydrophobic molecules from one side to the other. In this type of transport, we have proteins that form channels so those hydrophobic molecules can pass through the lipid membrane, and carrier proteins, which binds to a specific molecule changing their shape and transporting the molecule.
Active transport needs the<em> energy</em> to transport molecules; since it goes against the gradient's concentration. In this group, we have:
- Sodium-Potassium pump: uses ATP to move sodium outside the cell and potassium to the inside. The ions with this transport go to where they are most concentrated.
In conclusion, there are different types of transport; they depend on the concentration or type of molecule. To find out what mechanism of transport occurred in the lab, look at the components of the experiment and analyze which of these transports could be present.
Learn more at:
brainly.com/question/18565254
