Answer:
A callus is a hardening of skin, keratin is the protein which is abundant in callus. Skin is a protective layer against a external environment. Outer layer of skin consist of keratin which is also found in hair. Callus is the accumulation of dead cells result due to friction and pressure exerts on the part in which they are present. The keratin component (keratinocytes) remains undifferentiated in these dead cells which causes hardening in callus.
<u>Answer:</u>
Heat moves from the land to the air through the process of "conduction".
<u>Explanation:</u>
When the two things come in contact with one another at different temperatures or basically when heat flows from the warmer to the colder region or phase until both reach at the same temperature is understood as "conduction". Conduction is a physical process which occur by collision of the microscopically colliding particles like molecules, atoms and electrons on the movement of heat through a substance.
While convection take place by the movement of heated objects and it isn't the process influencing air and water temperature difference. The examples of conduction are like a radiator, a heating pad, sand can conduct heat etc.
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.
