Epinephrine and norepinephrine are two hormones that are released from the adrenal medulla when the body is under stress (like during exercise, for example) as a part of the sympathetic response.
These hormones have many functions and they all work together to prepare the individual for a fight or flight response -<em> like increasing heart rate and producing bronchodilatation</em>. One of these functions is the rise of glucose levels in blood which is important for this substance to reach several tissues, like the skeletal muscle. The skeletal muscle will make use of this glucose to produce ATP and generate the required energy for muscle contraction through a process called glycolysis, which is key for the fight or flight response mentioned above.
When we exercise, glucose levels rise thanks to these hormones so the skeletal muscle can have enough energy to contract and move as we want. If the exercise is too intense or prolongued, glucose levels will drop and other fuels will be needed to sustain this activity, like stored glycogen and fat.
The second statement is correct: "The "host range" for a virus is determined by the presence or absence of particular components on the surface of a host cell that are required for the virus to attach."
Explanation:
The virus attaching itself to the host cell is the first step for it to successfully infect the host. Viruses are smaller in size than bacteria, so the first statement is incorrect. The third statement is incorrect because viruses do not have the necessary machinery to carry out protein synthesis or to generate ATP, this precisely why they seek out a host to begin with. The fourth statement is false because the virus will either have DNA or RNA, but both at the same time.
Some energy in ATP is released to do work, such as move muscles or force a seedling out of the ground. ... Within the power plants of the cell (mitochondria), energy is used to add one molecule of inorganic phosphate (P) to a molecule of adenosine diphosphate (ADP).
This has something to do with winter seasons. You see, during winter days, <span>the sun is further down in the sky, so the same circle of sunlight covers a wider area, so there is less light per plant. In this case, those plants that are pointing straight at the sun have higher chances of growing better. Hope this answers your question.</span>
