The body has a mechanism for using it directly, and then several levels of mechanisms for transferring energy from other molecules to the formation of ATP (from ADP), which is then used directly. There are four levels of steps, each of which can be used for successively longer times, although at successively lower levels of activity (Table 6.8 ) …
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Figure 4.2 Ultimately, most life forms get their energy from the sun. Plants use photosynthesis to capture sunlight, and herbivores eat the plants to obtain energy. Carnivores eat the herbivores, and eventual decomposition …
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Creatine phosphate can supply the energy needs of a working muscle at a very high rate, but only for about 8–10 seconds. Glycogen (without oxygen) Fortunately, muscles also have large stores of a carbohydrate, called glycogen, which can be used to …
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Proteins are not stored for later use, so excess proteins must be converted into glucose or triglycerides, and used to supply energy or build energy reserves. Although the body can synthesize proteins from amino acids, food is an important source of those amino acids, especially because humans cannot synthesize all of the 20 amino acids used to build …
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The body uses food to (1) operate organs, (2) maintain a constant temperature by using some of the heat that is generated by operating the organs (while …
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Hydrolysis is the process of breaking complex macromolecules apart. During hydrolysis, water is split, or lysed, and the resulting hydrogen atom (H +) and a hydroxyl group (OH –) are added to the larger molecule. The hydrolysis of ATP produces ADP, together with an inorganic phosphate ion (P i ), and the release of free energy.
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The liver, like muscle, can store glucose energy as a glycogen, but in contrast to muscle tissue it will sacrifice its stored glucose energy to other tissues in the body when blood glucose is low. Approximately one …
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The body uses food energy differently. It does not burn its fuel as a log burns in the fireplace—combining rapidly with oxygen at a high temperature. Nevertheless, by actually burning a food sample in the laboratory and measuring the heat produced, we can find out how much energy a food potentially can give us.
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Glucose. A molecule of glucose, which has the chemical formula C 6 H 12 O 6, carries a packet of chemical energy just the right size for transport and uptake by cells. In your body, glucose is the "deliverable" form of energy, carried in your blood through capillaries to each of your 100 trillion cells. Glucose is also the carbohydrate produced ...
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Photoautotrophs. Photoautotrophs are autotrophs that use energy from sunlight to make organic compounds by photosynthesis. Photoautotrophs include plants, algae, and many bacteria, as shown in Table 24.5.1 24.5. 1. They are the primary producers in the vast majority of ecosystems on Earth.
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Adenosine triphosphate, or ATP, is the primary energy currency in cells; ATP stores energy in phosphate ester bonds. ATP releases energy when the phosphodiester bonds are broken and ATP is converted to ADP and a phosphate group. ATP is produced by the oxidative reactions in the cytoplasm and mitochondrion of the cell, where carbohydrates ...
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ATP is a nucleotide monomer. It''s composed of 3 subparts. Part 1 is the five-carbon sugar ribose. Part 2 is the nitrogenous base adenine, which is one of the letters of the genetic code. Part 3 consists of three phosphate groups (which is where the "triphosphate" part of ATP''s name comes from).
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36. Skeletal muscle metabolism. Describe the sources of ATP (e.g., glycolysis, oxidative phosphorylation, creatine phosphate) that muscle fibers use for skeletal muscle contraction. Explain the factors that are believed to contribute to skeletal muscle fatigue. Compare and contrast the metabolism of skeletal muscle with that of cardiac and ...
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The liver, like muscle, can store glucose energy as a glycogen, but in contrast to muscle tissue, it will sacrifice its stored glucose energy to other tissues in the body when blood glucose is low. Approximately one-quarter of total body glycogen content is in the liver (which is equivalent to about a four-hour supply of glucose) but this is highly dependent …
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Nutrients are used to produce energy, detect and respond to environmental surroundings, move, excrete wastes, respire (breathe), grow, and reproduce. There are six classes of nutrients required for the body to function and maintain overall health. These are carbohydrates, lipids, proteins, water, vitamins, and minerals.
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The energy required for muscle contraction is provided by the breakdown of ATP but the amount of ATP in muscles cells is sufficient to power only a short duration of contraction. Buffering of ATP by phosphocreatine, a reaction catalysed by creatine kinase, extends the duration of activity possible but sustained activity depends on continual …
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Whether directly (daily feeding) or indirectly (endogenous stores), carbohydrates, fat and protein supply the energy requirements for the human body …
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Figure 24.5.9 24.5. 9 summarizes the pathways of catabolism and anabolism for carbohydrates, lipids, and proteins. Figure 24.5.8 24.5. 8: Energy from Amino Acids Amino acids can be broken down into …
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All of the chemical reactions that take place inside cells, including those that use energy and those that release energy, are the cell''s metabolism. Figure 6.1.1 6.1. 1: Most energy comes from the sun, either directly or indirectly: Most life forms on earth get their energy from the sun. Plants use photosynthesis to capture sunlight, and ...
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In nearly every living thing on earth, the energy comes from the metabolism of glucose. In this way, ATP is a direct link between the limited set of exergonic pathways of glucose catabolism and the multitude of endergonic pathways that power living cells.
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ATP is hydrolyzed to ADP in the following reaction: ATP + H 2 O ⇋ ADP + P i + energy. Note: P i just stands for an inorganic phosphate group (PO 4 3 −) . Like most chemical reactions, the hydrolysis of ATP to ADP is reversible. The reverse reaction, which regenerates ATP from ADP and P i, requires energy.
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Fats serve useful functions in both the body and the diet. In the body, fat functions as an important depot for energy storage, offers insulation and protection, and plays important roles in regulating and signaling. Large …
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Abstract. The perception that intracellular lipolysis is a straightforward process that releases fatty acids from fat stores in adipose tissue to generate energy has experienced major revisions ...
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Figure 24.4.4 24.4. 4 summarizes the pathways of catabolism and anabolism for carbohydrates, lipids, and proteins. Figure 24.4.3 24.4. 3: Energy from Amino Acids. Amino acids can be broken down into precursors for glycolysis or the Krebs cycle. Amino acids (in bold) can enter the cycle through more than one pathway.
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Mitochondria are necessary for the energy supply of neurological cells, as their energy consumption is incredibly high, with the brain as one of the most …
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ATP functions as the energy currency for cells. It allows cells to store energy briefly and transport it within itself to support endergonic chemical reactions. The structure of ATP is that of an RNA nucleotide with three phosphate groups attached. As ATP is used for energy, a phosphate group is detached, and ADP is produced.
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Carbohydrates, protein, fats, and alcohol—the dietary macrocomponents—are the sources of energy in the diet. Under normal circumstances, more than 95% of this food energy is digested and absorbed from the gastrointestinal tract to provide the body''s energy needs. Studies of normal and overweight subjects have not shown any significant differences in …
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How our bodies harness energy. Jennifer Doody. Harvard Correspondent. April 29, 2016 4 min read. It''s the cells that have to prioritize their workload. In exploring how humans …
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The energy used in post-prandial state during rest and physical activity is derived predominantly from the oxidation of carbohydrate (CHO) and fat. Although protein can also serve as a source of energy, …
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The liver, like muscle, can store glucose energy as a glycogen, but in contrast to muscle tissue it will sacrifice its stored glucose energy to other tissues in the body when blood glucose is low. Approximately one-quarter of total body glycogen content is in the liver (which is equivalent to about a four-hour supply of glucose) but this is highly dependent …
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There are two mechanisms of ATP synthesis: 1. oxidative phosphorylation, the process by which ATP is synthesized from ADP and inorganic phosphate (Pi) that takes place in mitochondrion; and 2....
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4 · Energy Metabolism and ATP Synthesis in Human Cells. Figure 1: Schematic representation of fuel molecule entry points in oxidative metabolism. Degradation of lipids, proteins, and carbohydrates ...
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Metabolism is the set of life-sustaining chemical processes that enables organisms transform the chemical energy stored in molecules into energy that can be used for …
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