Answer:
The preceding section reviewed the major metabolic reactions by which the cell obtains and stores energy in the form of ATP. This metabolic energy is then used to accomplish various tasks, including the synthesis of macromolecules and other cell constituents. Thus, energy derived from the breakdown of organic molecules (catabolism) is used to drive the synthesis of other required components of the cell. Most catabolic pathways involve the oxidation of organic molecules coupled to the generation of both energy (ATP) and reducing power (NADH). In contrast, biosynthetic (anabolic) pathways generally involve the use of both ATP and reducing power (usually in the form of NADPH) for the production of new organic compounds. One major biosynthetic pathway, the synthesis of carbohydrates from CO2 and H2O during the dark reactions of photosynthesis, was discussed in the preceding section. Additional pathways leading to the biosynthesis of major cellular constituents (carbohydrates, lipids, proteins, and nucleic acids) are reviewed in the sections that follow.
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Carbohydrates
In addition to being obtained directly from food or generated by photosynthesis, glucose can be synthesized from other organic molecules. In animal cells, glucose synthesis (gluconeogenesis) usually starts with lactate (produced by anaerobic glycolysis), amino acids (derived from the breakdown of proteins), or glycerol (produced by the breakdown of lipids). Plants (but not animals) are also able to synthesize glucose from fatty acids—a process that is particularly important during the germination of seeds, when energy stored as fats must be converted to carbohydrates to support growth of the plant. In both animal and plant cells, simple sugars are polymerized and stored as polysaccharides.
Gluconeogenesis involves the conversion of pyruvate to glucose—essentially the reverse of glycolysis. However, as discussed earlier, the glycolytic conversion of glucose to pyruvate is an energy-yielding pathway, generating two molecules each of ATP and NADH. Although some reactions of glycolysis are readily reversible, others will proceed only in the direction of glucose breakdown, because they are associated with a large decrease in free energy. These energetically favorable reactions of glycolysis are bypassed during gluconeogenesis by other reactions (catalyzed by different enzymes) that are coupled to the expenditure of ATP and NADH in order to drive them in the direction of glucose synthesis. Overall, the generation of glucose from two molecules of pyruvate requires four molecules of ATP, two of GTP, and two of NADH. This process is considerably more costly than the simple reversal of glycolysis (which would require two molecules of ATP and two of NADH), illustrating the additional energy required to drive the pathway in the direction of biosynthesis.
Answer:
A. They center on the motives of wrongdoers as well as on the amount of damage done when assigning blame.
Explanation:
The Concrete Operational Stage, according to Piaget, refers to a stage that begins around age 7 and ends around the ages of 11 or 13.
During this stage, children are now capable of thinking in a more logical manner and their moral judgement has become subjective as <u>they now center on the motives of wrongdoers as well as on the amount of damage done when assigning blame</u>. For instance, they are able to judge another child according to the amount of damage she/he has done and whether it was done in purpose or accidentally.
They can also center on two dimensions of a problem at once and have thoughts that involve tangible objects instead of abstract ideas.
The correct answer is D. Without capsids, viruses could not replicate
Explanation:
A viral infection is caused as a virus enters the body and this replicates inside it by using the host's cells. This is possible through the capsid which is an external layer in the virus that provides protection to it and helps the virus replicate because the capsid is essential for the virus to attach and penetrate the host's cells to replicate. According to this, if a drug damages the capsids the virus could not replicate and this should or reduce the infection caused by the virus. Thus, a drug that damages capsids helps treat a viral infection because "without capsids, viruses could not replicate".
Answer:
B 20 amino acids, hundreds of proteins
Explanation:
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The answer would be C because people destroying rain forests for homes and resources are diminishing animal homes and animal population <span />
