Organisms are highly organized and complex, maintaining a state of low entropy within their bodies. According to the second law of thermodynamics, which states that the entropy of the universe is always increasing, how is this maintenance of order possible for a living organism?

When ethanol (alcohol) is consumed, the body detoxifies it by first breaking it down to acetaldehyde, a toxic carcinogen, and then converting the acetaldehyde into acetate, which is further broken down and eliminated. Acetaldehyde binds to the active site of the enzyme acetaldehyde dehydrogenase (ALDH2 in humans). The medication disulfiram binds to a different site on the enzyme ALDH2, changing its shape and preventing acetaldehyde from binding. This causes a buildup of acetaldehyde at even low levels of alcohol consumption, leading rapidly to symptoms of a hangover including flushing, headache, nausea, sweating, and vomiting, among others. By producing such an acute sensitivity to drinking alcohol, disulfiram has been used as a medication to treat chronic alcoholism. Given that it binds to a different site than acetaldehyde on ALDH2, disulfiram is an example of what kind of inhibitor?

Unit 3 ExamChapters 17, 14, 1550 questions75 points50 minutes

Which of the following is the best estimate of a corporation’s cost of debt?

The duodenum, the initial part of the small intestine, has a pH of about 6.0. It receives chyme, a mixture of gastric juices and partially digested food from the stomach, that has a pH ranging between 1.5 and 3.5. If chyme with a pH of 2.0 passes into the duodenum with a pH of 6.0, how does the pH of each of these compare? 

With our model of the corporation, if a corporation invests in a project whose financial value is greater than its initial cost., which of the following with occur?

Adenosine triphosphate (ATP) is the primary energy currency of the cell. Its structure consists of a nitrogenous base called adenine, a five-carbon sugar called ribose, and three phosphate groups. Based on these components, ATP is classified as which type of macromolecule?

Carotenoids are accessory pigments found in plant leaves that can absorb light energy in the blue-green range. What is the importance of these pigments?

In a neuron, a concentration gradient of sodium ions (Na+) is maintained across the cell membrane by the sodium-potassium pump, with a higher concentration outside the cell than inside. What type of energy is stored in this concentration gradient, and how is it used by the cell?

The human stomach produces gastric acid with a pH between about 1.5 to 3.5. If an individual with a gastric acid pH of 2.0 drinks coffee with a pH of 5.0, how does the pH of each of these (the gastric acid and coffee) compare?