1) Directions for the students: There are 4 essay questions. Please be sure to complete all of them with thorough substantive responses. Citations are required for all responses. There is no time limit.Provide an example of an organism within each of the four main nutritional categories of microbes and describe how each obtains its essential nutrients.Provide evidence in support of or refuting the following statement: Microbial life can exist in the complete absence of both sunlight or organic nutrients.Polymerase chain reaction (PCR) is a technology that requires high temperatures to reproduce DNA fragments. Explain why the discovery of thermophilic archaea and their associated DNA polymerases was critical to the success of this technique.Summarize how the electron transport chain functions to produce ATP in a bacterial cell versus eukaryotic cell. Explain whether or not the term chemiosmosis accurately illustrates this process.2)For the Week 3 Critical Thinking Exercise, you will answer the following questions using your critical thinking and reasoning skills:1. Common side effects for someone experiencing shock include: a weak pulse, pale skin, cool skin, and tachycardia. Explain the physiological basis for each of these signs.2. Why is it advantageous to have baroreceptors in the aortic arch and carotid sinus rather than in some other location?3. It is a common untrained assumption that systolic blood pressure should be 100 plus a person’s age. Discuss the validity of this statement.Task 1: Create a new discussion post on or before Friday at 11:55pm EST by clicking the **REPLY HERE** post. Your initial response to this activity should include your answer to each of the questions above. Each answer should include a minimum of 5 sentences. For instance, if there are 2 questions above, your response should include at least 10 sentences (5 per answer). Going over the minimum sentence requirement is acceptable; however, I am not looking for an essay