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.
The heart’s electrical system is responsible for making and conducting signals that trigger the heart to beat. These signals cause the heart’s muscle to contract. With each contraction, blood is pumped throughout the body. This happens 24/7 without us having to monitor it all the time so that our heart does not stop.
The heart must beat faster during exersise because by increasing the heart rate the body is able to increase cardiac output and deliver the necessary blood flow to the mucles
Not all inspired air reaches the alveoli; 150 ml is stopped in the airway leading to the alveoli. This is called dead air space.
Alveoli are the tiny air sacs present all over the lungs. These are supposed to increase the surface area of the lungs so as to increase the amount of inhaled air. The exchange of oxygen and carbon dioxide takes place through these alveoli.
Dead air space is the unventilated area where air circulation does not take place. This air is supposed to be get trapped somewhere in the respiratory pathway or it reaches an alveoli that is poorly perfused. The dead air space can be of two types: anatomical dead space and physiologic dead space.
To know more about dead air space, here
brainly.com/question/14505996
#SPJ4
