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.
They are both in the same cell
Answer:
Nowadays energy generation heavily relies on fossil fuels causing environmental challenges. The global biofuels supply has increased by a factor of 8% since 2010, but only comprises 4% of the world’s transport fuels in 2015. The development of next generation of biofuel becomes increasingly important due to the depletion of fossil fuels and in the meantime to overcome challenges for current biofuels production – high cost and low efficiency. The biological production of lipid droplets in oleaginous microorganisms like microalgae, yeast, fungi, and bacteria becomes a promising path to the next generation of biofuels.
The lipid droplet (LD) is a cellular organelle that consists of a neutral lipid, mainly of triacylglycerols (TAGs) and cholesteryl esters, cored with a monolayer-phospholipid membrane and associated proteins. Lipid droplets widely exist in both prokaryotic and eukaryotic cells, could be collected and extracted for biofuel manufacturing. However, this technology is now limited in lab research. Methods to improve the lipid droplet production in oleaginous microorganisms, biomass pretreatment, lipid droplet extraction, industrial scalability are still under development. The experience of liposome manufacturing provides us a solid ground for lipid droplet studies and helps our clients move to a further step of new biofuel development.
Explanation:
https://www.creative-biostructure.com/Lipid-Droplets-Biofuel-Supply-626.htm
Explanation:
What happens during daytime is, oxygen that gets trapped between filaments of algae, moves them to the surface and during night as O2 is not produced, they slowly sink to lower depths, and you don't see them
Answer:
The muscles of the body is entirely made of proteins. They help in the making the connective tissue in the tendons of the body.
Explanation:
A. Making up the connective tissue in tendons
