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. Plant
Explanation:
Plants have some of the most of complex cells of living organisms because they have different roles and structures to enable the plant to survive.
These include cells like the Parenchyma, Collenchyma, Sclerenchyma, Xylem and Phloem cells. Xylem cells for instance are complex cells located within the vascular tissues of plants and help transport water and minerals to the rest of the plant from the roots. Xylem cells look long and tracheal which is to enable them carry out the aforementioned roles.
Answer:
No.
Explanation:
Hepatitis C is the most common bloodborne pathogen.
Hepatitis C as of 2022 has a infection rate of 3.7 million.
Hepatitis B as of 2022 has a infection rate of 2.2 million, or <em>1.5 million</em> lower than Hepatitis C.
Therefore, Hepatitis B is not the most common bloodborne pathogen.
Learn more about Hepatitis B, here:
brainly.com/question/6284143 - The three bloodborne pathogens healthcare workers in the US are most likely to be exposed to.
Type 1 Diabetic here! I can help!! so basically the receptor for insulin is a large protein that binds to insulin and passes its message into the cell. It has several functional parts. Two copies of the protein chains come together on the outside of the cell to form the receptor site that binds to insulin.
I hope this helped :)
