Two Co2 molecules are produced per citric acid cycle. Since the citric acid cycle occurs twice with every molecule of glucose metabolized, a total of 4 C02 molecules are produces for every glucose molecule
Explain why photosynthesis and cellular respiration are considered to be paired processes?
Well a first give away is that one is endothermic and one is exothermic. Also photosynthesis is just the flip around of the cellular respiration process but just add energy and the catalyst used
How does the human body obtain reactants for cellular respiration?
The human body obtains reactants for cellular respiration through the digestion of food. Carbohydrates, fats, and proteins from the food we eat are broken down during digestion into glucose, fatty acids, and amino acids, which are then used as reactants in cellular respiration to produce energy in the form of ATP.
What types of organisms use photosynthesis?
Plants, algae, and some types of bacteria are examples of organisms that use photosynthesis to convert sunlight into energy. They contain chlorophyll, a pigment that absorbs light energy and initiates the process of photosynthesis.
A measurement of those substances in water other than water molecules is referred to as?
Total dissolved solids (TDS). TDS represents the combined content of all inorganic and organic substances contained within a liquid, usually measured in mg/L or ppm.
Carbon dioxide enters bloodstream through the air sacs?
Yes, carbon dioxide diffuses from the alveoli in the lungs into the bloodstream. This gas exchange occurs due to differences in partial pressures of carbon dioxide between the alveoli and the blood. Once in the bloodstream, carbon dioxide is transported to the lungs to be exhaled out of the body.
Where does photosynthesis take place in the plant?
It takes place in chloroplasts, usually found in the leaves, where chlorophyll is used to catalyze the process.
More specifically, it takes place in the stacks (grana) of thylakoid disks within the chloroplasts.
In what part of the plant does most photosynthesis happen?
In vascular plants with leaves, the upper or sunward sides of the leaves will have the most photosynthetic activity. In other plants, such as kelp or cacti, the sunward-facing surfaces of the plant will have the most photosynthetic activity.
What role do NADH and FADH2 play in the process of cellular respiration?
ATP has a high energy bond that can be broken to supply power to most of the cell.
NAD is a co-enzyme that is mainly absorbed from food or produced naturally in the body from certain nutritional elements, by means of various biochemical processes. Most niacin in food is in the form of NAD or NADP. Niacin is absorbed in the small intestine, mostly in the form of NAD or NADP. NAD is mainly obtained from the NAD that is present in food. NAD can be produced in the liver, in particular, under the control of the hormones that are secreted by the adrenal glands. Nicotinamide is an important precursor of NAD, under physiological conditions. Tryptophan is another important precursor of NAD and the body obtains a large proportion of NAD from this source. In the case of human nutrition, 60 mg tryptophan is the equivalent of 1 mg niacin.
BIOCHEMICAL FUNCTIONS OF NAD NAD was the first co-enzyme to be identified in 1905 by Harden and Young. NAD has more than 100 functions in the human metabolism. Even the activity of the citric-acid cycle, which is found in most cells, becomes restricted in the lack of NAD and NADP. The body constantly requires NAD and if the NAD level becomes too low, the need for it is activated in the primitive part of the brain. This biochemical action cannot be controlled by the mind or changed by willpower. Alcohol and the metabolites, which it creates, suppress this need for NAD. Excessive exercising and the associated secretion of endorphins also suppress the need for NAD. 1 Metabolic Detoxification of Chemical Substances NAD does not have the same side-effects as nicotinic acid at high dosages, like serious flushing and the release of histamine. The intracellular metabolism of alcohol, and possibly also of other chemical substances, requires NAD or derivatives thereof, in order to take place. Ninety per cent of alcohol is absorbed almost immediately in the body's cells; the remaining 10% is discharged mainly in the urine. Acetaldehyde is the first metabolite of various chemical substances, including alcohol, that is produced. Acetaldehyde is also formed during stress. Acetaldehyde is used as a preservative in certain dairy products. The last step in the metabolic detoxification process occurs in the citric-acid cycle, where three NADs are involved in the process. This cycle is also responsible for the conversion of proteins, carbohydrates and fats into ATP. This is a purely biochemical autonomic reaction, and neither the person's will or any other form of control can be exercised over it. The biochemical reactions can be simplified as follows: Chemical Substance + NAD -> Acetaldehyde + NAD -> Acetate + CoA -> Acetyl-CoA +3NAD(H) -> ATP + H2O + CO2 + Heat Ethanol toxicity is closely related to its metabolism in the liver. The elevated NADH/NAD ratio (ie NAD deficiency) results in alterations of the intermediary metabolism of lipids, carbohydrates, proteins, purines, hormones and porphyrins. This shift in metabolic pathways results in hyperlactacidaemia, lactacidosis, ketosis and hyperuricaemia. Furthermore, excess NADH can results in free radical production. The NADH that builds up, eg during eg alcohol metabolism, will drive pyruvate to lactate which can lead to acidosis. The pyruvate is now not available for gluconeogenesis and if, as is common in serious alcoholism, the patient is not eating properly, hypoglycemia can result. The high NADH/NAD ratio will affect other processes such as b-oxidation. One clinical manifestation is liver disorders associated with alcoholism: fatty liver, alcoholic hepatitis and, sometimes, cirrhosis. The burden on oxidizing systems also leads to increased use of the P450 or microsomal oxidizing system which can have important effects on steroid metabolism and other processes involving this system. 2 Repairing DNA NAD and niacin (a precursor of NAD), play an important role in defending cells against DNA damage by genotoxic particles. Research shows that niacin supplementation, particularly for persons who initially have lower levels, improves the level of NAD in blood and lymphocytes. NAD plays a major role in repairing DNA. Research shows that damage to DNA can possibly stimulate the biosynthesis of NAD and that the repair of DNA can be increased and accelerated in cells with increased levels of NAD112. Cytotoxic substances reduce the intracellular levels of NAD and can lead to the death of cells. DNA strand breakage decreased proportionately to NAD concentrations over time in lymphocytes exposed to oxygen radicals. The results suggest a general correlation between DNA damage and acute lowering of cellular NAD pools. "Rejoining of DNA single-strand breaks generated by treatment of plasmids with gamma-rays, neocarzinostatin, or bleomycin was catalyzed inefficiently by human cell extracts. The reaction was strongly promoted by the addition of NAD+, which was employed for rapid and transient synthesis of poly(ADP-ribose)... NAD(+)-promoted DNA repair by soluble cell extracts also occurred with alkylated DNA as substrate and was suppressed by 3-aminobenzamide. A similar stimulatory effect by NAD+ was observed for repair of ultraviolet-irradiated DNA, and this could be ascribed to the presence of pyrimidine hydrates as minor radiation-induced DNA lesions". 3 Generating Energy During one of our dietitian's lectures in Nutritional Biochemistry at Pretoria University, an individual's theoretical daily need for NAD, assuming that none is recycled, was calculated. The calculation showed, that the average person's body contains approximately 16 grammes of NAD and that it had to be recycled 2 160 times during every 24 hours through the body. Had the body lacked the ability to recycle NAD successfully, 35,91 kg of NAD (approximately 72 000 containers of NutriNAD, or 7,2 million MultiNAD or MalaikaNAD capsules) would have to be taken every day, in order to supplement it. NAD plays an important role in the production of ATP (the basic energy molecule) in the body. NAD and NADP, which are pyridine nucleotides, are rated as being amongst the important high energy compounds in the biochemistry of organisms. The reduction of NAD plays an important part in the citric-acid cycle and contributes to the production of 22 molecules of ATP from one molecule of glucose. NAD and its derivatives NADH, NADP and NADPH have regulatory functions in the generation of triose phosphates and pyruvate from glucose. NAD is reduced to NADH in the metabolism of glucose. The hydrogen molecule is obtained from the metabolism of fats, carbohydrates and proteins. The activated NADH plays a part in several critical bodily functions, amongst others, in the continued production of ATP, which is the basic energy compound in the body. NAD plays an important role in the release of energy from carbohydrates, fats and proteins. In the absence of oxygen, pyruvate must be converted to lactate to regenerate NAD from NADH in the cytoplasm. In the presence of oxygen, the mitochondria can reoxidize cytosolic NADH by an indirect process, involving the mitochondrial "shuttle systems". 4 Improving Immunity Phagocytes use NADPH as a source of energy, to destroy pathogens. The NAD(P)H, that is available, is also used to protect the body against free radicals and to, in this way, prevent illnesses and damage. High dosages of ascorbic acid can supplement the activity of the NAD(P)H, which is only available to a limited extent. Research on the effect of the Epstein-Barr virus on lymphocytes, indicates that the cultivated cells' levels of NAD were lower. The addition of NAD restored the levels within two hours. The study also discusses the effect of NAD on the mitochondrial metabolism and the relationship between NAD and the activity of complex I in cultured human cells. .5 Improving Brain Functions The brain is metabolically speaking one of the most active organs in the body and consumes approximately 20% of all energy generated. Its weight-to-energy ratio is ten times more than that of most other organs. The brain does not really have any reserves of energy, in the true sense of the word, and must therefore be supplied continuously with energy by the body. The brain, as a whole, consumes approximately 4 x 1021 molecules of ATP per minute and this increases during REM sleeping. During the first ten years of a child's life, the brain consumes up to twice as much energy as during adulthood. When pyruvate oxidation is impaired, glycolysis will run faster than normal to try to make up for deficient ATP production. This will cause more production of lactate. The brain relies on oxidation of glucose as an energy source and has a limited ability to oxidize fatty acids. In cases of severe energy depletion mental retardation is not surprising. NAD plays an important part in the production of ATP in cells. Derivatives of niacin, mainly in the form of NAD and NADP coenzymes, are found abundantly in brain tissue. In the case of niacin deficiency, the brain's supply of NAD declines sharply and the functioning of the brain is disturbed; malfunctioning of the brain (dementia) is indeed one of the primary characteristics of pellagra. If the NAD deficiency lasts for an extended period, permanent brain damage develops. Scientists have discussed the possible use of NAD for the treatment of neurodegeneration155 and the improvement of brain functions. NADH plays a role in the synthesis of the neurotransmitters, i.e. noradrenaline and dopamine, which are important for maintaining a positive state of mind. South African research on NAD, that was conducted for the manufacturer, also confirms the normalising effect of NAD on the neurotransmitters, i.e. dopamine, adrenaline and noradrenaline. NAD probably plays a role in the production of serotonin and other neurotransmitters in the brain. 6 Normalizing Cell Functions "The corepressor CtBP (carboxyl-terminal binding protein) is involved in transcriptional pathways important for development, cell cycle regulation, and transformation. We demonstrate that CtBP binding to cellular and viral transcriptional repressors is regulated by the nicotinamide adenine dinucleotides NAD+ and NADH". "NAD is the substrate of a novel chromatin-associated enzyme-ADP-ribosyl transferase (ADPRT). In this study, the cell-cycle dependent change in cellular NAD content was observed in a line of human amnion FL cells. It was found that the cellular NAD content of FL cells was highest in G1 and lowest in S/G2-G2. 3AB, a potent ADPRT inhibitor, can inhibit the cell cycle dependent change in cellular NAD content and also inhibit DNA synthesis in the S phase and extend the S phase. The results indicate that ADP-ribosylation may be involved in DNA replication and cell cycle progression. It was also found that the DNA-damaging agents, MNNG, MMS and 4NQO could lower cellular NAD content in a dose-dependent way". "Hepatocytes were found to be remarkably resistant to suicidal NAD+ depletion due to consumption for chromatin-associated poly(ADP-ribose) biosynthesis, which normally follows infliction of DNA damage in mammalian cells... This differential behavior, demonstrable also with other carcinogens, can be attributed to the different NAD+ biosynthetic capacities of these cells".781 "Marked depletion of intracellular NAD+ prior to toxicity and a protection against toxicity associated with maintenance of NAD+ suggest a possible role for the maintenance of intracellular NAD+ in cellular integrity." "Many cellular enzymes use NAD+ as coenzyme or substrate, depending on the nature of the enzymatic reaction. Under certain conditions the cellular NAD+ concentration may become rate-limiting for such enzymes. For instance, when eucaryotic cells are exposed to high concentrations of DNA-damaging agents, the resulting DNA strand breaks may stimulate the nuclear enzyme poly(ADP-ribose) polymerase (PARP) to such an extent that the cellular pool of NAD+, which is the substrate for this enzyme, is severely depleted, possibly leading to acute cell death". "When mouse leukemia cells are treated with gamma-radiation or neocarzinostatin the intracellular NAD and ATP levels fall rapidly. We have shown that the ATP response is a consequence of the decreased NAD level. We suggest that this low NAD level results in decreased glycolytic activity and that there is a subsequent accumulation of phosphorylated sugars associated with the fall in ATP. Under these extreme conditions, therefore, the NAD level probably regulates the rate of glycolysis in cells which are utilising a rapidly metabolisable sugar as their energy source". "Ionizing- and ultraviolet-radiation cause cell damage or death by directly altering DNA and protein structures and by production of reactive oxygen species (ROS) and reactive carbonyl species (RCS). These processes disrupt cellular energy metabolism at multiple levels. The formation of DNA strand breaks activates signaling pathways that consume NAD, which can lead to the depletion of cellular ATP. Poly(ADP)-ribose polymerase (PARP-1) is the enzyme responsible for much of the NAD degradation following DNA damage, although numerous other PARPs have been discovered recently that await functional characterization. Studies on mouse epidermis in vivo and on human cells in culture have shown that UV-B radiation provokes the transient degradation of NAD and the synthesis of ADP-ribose polymers by PARP-1... Identifying approaches to optimize these responses while maintaining the energy status of cells is likely to be very important in minimizing the deleterious effects of solar radiation on skin". "Peroxynitrite and hydroxyl radicals are potent initiators of DNA single strand breakage, which is an obligatory stimulus for the activation of the nuclear enzyme poly(ADP-ribose)synthetase (PARS). Rapid activation of PARS depletes the intracellular concentration of its substrate, NAD+, slowing the rate of glycolysis, electron transport and ATP formation. This process can result in acute cell dysfunction and cell necrosis. Accordingly, inhibitors of PARS protect against cell death under these conditions. In addition to the direct cytotoxic pathway regulated by DNA injury and PARS activation, PARS also appears to modulate the course of inflammation by regulating the expression of a number of genes... In vivo data demonstrate that inhibition of PARS protects against various forms of inflammation, including zymosan or endotoxin induced multiple organ failure, arthritis, allergic encephalomyelitis, and diabetic islet cell destruction". "Recent studies point to the naturally occurring molecules in expression of radiation damage and in protection. DNA repair was shown to be one of the parameters that can be modified to attain improved protection. The need for a natural compound that can enhance DNA repair in order to improve cellular protection focused our attention on nicotinamide (NA). The effects of addition of NA, a precursor for NAD+ synthesis, on the DNA repair capacity following gamma and ultraviolet irradiations were studied in several repair-proficient and repair-deficient cell lines. The addition of low concentrations of NA (less than 3 mM) resulted in increased repair synthesis in the repair-proficient cells. Addition to repair-deficient cells resulted in decreased repair synthesis. Cells which repair damage from one type of radiation, and not from another, responded accordingly to the presence of NA. However, addition of high concentrations of NA to repair-proficient cells resulted in decreased repair synthesis. Thus, nicotinamide can improve the repair capacity in a concentration-dependent manner, but it clearly requires the existence of functional repair processes." "An intimate relationship exists between DNA single-strand breaks, NAD metabolism, and cell viability in quiescent human lymphocytes. Under steady-state conditions, resting lymphocytes continually break and rejoin DNA. The balanced DNA excision-repair process is accompanied by a proportional consumption of NAD for poly(ADP-ribose) synthesis. However, lymphocytes have a limited capacity to resynthesize NAD from nicotinamide. An increase in DNA strand break formation in lymphocytes, or a block in DNA repair, accelerates poly(ADP-ribose) formation and may induce lethal NAD and ATP depletion". "These data indicate for the first time hormonal modulation of NADase resulting in two signals: (1) enhancement of NAD+ which may explain the increase in ADP ribosylation and activation of cholera-toxin substrates leading to facilitation of protein secretion; (2) suppression of cell cADP-ribose and consequently intracellular Ca2+ which may explain the melatonin-induced inhibition of protein secretion". "Extracellular NAD is degraded to pyridine and purine metabolites by different types of surface-located enzymes which are expressed differently on the plasmamembrane of various human cells and tissues... ATP was found to be the main labeled intracellular product of exogenous NAD catabolism; ADP, AMP, inosine and adenosine were also detected but in small quantities... These results confirm that adenosine is the NAD hydrolysis product incorporated by cells and further metabolized to ATP, and that adenosine transport is partially ATP dependent". Copyright article from the E-book NAD Therapy To Good Too Be True? Theo Verwey and Clinicians - see also http://www.nutrimalaika.net
What part of the water molecule is used during photosynthesis?
The hydrogen atoms in the water molecule are used during photosynthesis. Water molecules are split into oxygen, protons, and electrons during the light-dependent reactions in photosynthesis.
What effect does low temperature have on photosynthesis?
Low temperatures can slow down the rate of photosynthesis because the enzymes involved in the process become less active. This can lead to reduced carbon dioxide fixation and ultimately lower production of glucose and oxygen. Extremely low temperatures can even damage the plant cells and photosynthetic machinery, affecting overall growth and survival.
What effect would the presence of potassium hydroxide have on photosynthesis?
Potassium hydroxide is a strong base that can disrupt the pH balance in a plant cell, affecting enzyme activity and potentially inhibiting photosynthesis. This disruption may alter the functioning of chloroplasts and other cellular processes involved in photosynthesis, leading to a decrease in the overall rate of photosynthesis.
Why are carbon dioxide detectors used in border control?
they were used in border control because they were trying to stop illegal immigrints going from country to country;so the detectors monitor the level of co2 in the lorry and if it is over a certain number they searched the lorry
wolfiepagefan001
What does NADPH provide in the Calvin benson cycle?
NADPH provides reducing power in the Calvin cycle, enabling the conversion of carbon dioxide into sugars. It is essential for the reduction of 3-phosphoglycerate to glyceraldehyde-3-phosphate, which is a key step in the cycle for the production of carbohydrates.
Why is aerobic respiration the opposite of photosynthesis?
Aerobic respiration is the opposite of photosynthesis because in respiration, organisms break down glucose and oxygen to produce carbon dioxide, water, and energy, while in photosynthesis, plants use carbon dioxide, water, and sunlight to produce glucose and oxygen. The processes have opposite inputs and outputs, with respiration releasing energy and photosynthesis storing energy.
Why is photosynthesis referred as to a biochemical pathway?
Photosynthesis is referred to as a biochemical pathway because it involves a series of chemical reactions that occur within plant cells. These reactions convert light energy into chemical energy stored in the form of glucose. The process is highly regulated and involves multiple steps that are catalyzed by specific enzymes.
Which part of a flowering plant captures the most sunlight for photosynthesis?
The leaves of a flowering plant capture the most sunlight for photosynthesis. They contain chlorophyll, the pigment that absorbs sunlight and converts it into energy through photosynthesis. Leaves are specifically adapted to maximize their surface area for efficient light capture.
The Calvin cycle converts carbon dioxide to?
The Calvin cycle converts carbon dioxide to glucose, a process known as carbon fixation. By using energy from light and enzymes, the Calvin cycle transforms CO2 molecules into sugars that can be used by the plant for energy.
What plants are involved in photosynthesis?
All plants, some protists, bacteria and blue green algae uses the sun to make photosynthesis. Plants use photosynthesis to create energy that then makes sugar for nutrient.
Why is photosynthesis necessary in order for us to breathe?
Photosynthesis is necessary for us to breathe because it produces oxygen as a byproduct. During photosynthesis, plants take in carbon dioxide and water and convert them into glucose and oxygen using sunlight. The oxygen released by plants during this process is what we breathe in to survive. Without photosynthesis, oxygen levels in the atmosphere would significantly decrease and make it difficult for us to breathe.
How does the leaf's thickness affect the rate of photosynthesis?
Leaf thickness is largely due to the thickness of the palisade mesophyll layer. This is where the chloroplast is located and therefore the site area in light is absorbed for photosynthesis. Thicker leaves means more chloroplast, and thus a faster rate of photosynthesis.
What is the function of water in a leaf?
Water in a leaf is crucial for photosynthesis, where it serves as a medium to transport nutrients and minerals throughout the leaf. Additionally, water helps maintain the turgidity of the leaf cells, providing structural support and enabling gas exchange through stomata.
What happens to the sugar produced in the leaves of a plant?
The sugar produced in the leaves of a plant is transported down to the roots, stems, and other parts of the plant through specialized tubes called phloem. This sugar is used as a source of energy for growth, maintenance, and reproduction in different parts of the plant.
Test for starch in a leave by photosynthesis?
Test for Starch 1. Heat some water to boiling point in a beaker then turn out the Bunsen flame. 2. Use forceps to dip a leaf in the hot water for about 30 seconds. This kills the cytoplasm, dentures the enzymes and makes the leaf more permeable to iodine solution. 3. Push the leaf to the bottom of a test tube and cover it with alcohol (ethanol). Place the tube in the hot water. The alcohol will boil and dissolve out most of the chlorophyll. This makes colour changes with iodine easier to see. 4. Pour the green alcohol into a spare beaker, remove the leaf and dip it once into the hot water to soften it. 5. Spread the decolourized leaf flat on a white tile and drop iodine solution onto it. The parts containing starch will turn blue; parts without starch will stain brown or yellow with iodine
What came first in evolution cellular respiration or photosynthesis?
Cellular respiration likely evolved before photosynthesis. Early prokaryotic organisms likely developed cellular respiration to generate energy from organic molecules. Photosynthesis evolved later in some prokaryotic organisms as a way to use sunlight to make energy.