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Importance of photosynthesis to man
Importance of photosynthesis to man
Importance of photosynthesis Essay
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Categories of Life All living things fall into two main categories based on how they obtain chemical energy. There are autotrophs and heterotrophs. Autotrophs are “an organism that uses energy from an external source, such as sunlight, to produce its own food without having to eat other organisms or their remains (page g14).” Within the food web, autotrophs are identified as producers because they convert the energy from sun into the energy they need through photosynthesis and are plants, algae and even some bacteria. In contrast, heterotrophs are “an organism that obtains its energy by eating other organisms or their remains (page g4).” Consumers include herbivores, carnivores, and decomposers. While autotroph are recognized by many in the …show more content…
Glucose is needed to create the body’s source of energy, ATP, and is found in carbohydrates. Since heterotrophs are unable to produce the food, or glucose, they need for cellular respiration, they obtain this food by consuming autotrophs or other heterotrophs. When a carbohydrate is consumed it begins its journey by traveling through several digestive organs, including the stomach and the small intestine, where it is broken down into the glucose the body needs to create energy. An organ is composed of different tissues that have come together to function in a coordinated manner (textbook page 20, para 7). Therefore digestive organs are organs that work together to breakdown food into the nutrients needed for the organism to function. Once the carbohydrate has been broken down into glucose, through a process of absorption, it enters the blood stream and is transported to cells where it undergoes a chemical process where the glucose is converted to …show more content…
The two 3-carbon pyruvate molecules that were created from glycolysis are oxidized. One of the carbon bonds on the 3-carbon pyruvate molecule combines with oxygen to become carbon dioxide. The carbon dioxide leaves the 3-carbon pyruvate chain. The remaining 2-carbon molecules that are left over become acetyl coenzyme A. Simultaneously, NAD+ combines with hydrogen to become NADH. With the help of enzymes, phosphate joins with ADP to make and ATP molecule for each pyruvate. Enzymes also combine acetyl coenzyme A with a 4-carbon molecule called oxaloacetic acid to create a 6-carbon molecule called citric acid. The cycle continuously repeats, creating the byproduct of carbon dioxide. This carbon dioxide is exhaled by the organism into the atmosphere and is the necessary component needed to begin photosynthesis in autotrophs. When carbon is chemically removed from the citric acid, some energy is generated in the form of NAD+ and FAD. NAD+ and FAD combine with hydrogen and electrons from each pyruvate transforming them into NADH and FADH2. Each 3-carbon pyruvate molecule yields three NADH and one FADH2 per cycle. Within one cycle each glucose molecule can produce a total of six NADH and two
2. The conversion of pyruvate to acetaldehyde is done by the release of CO₂ and enzyme pyruvate decarboxylase.
While the trophic level of primary producers is of autotrophs, the next remaining levels all represent heterotrophs. Heterotrophs can only obtain their energy by consuming of other organisms. In the tropic level of the primary consumers, these herbivores depend on these primary producers and other plants for their food. An example of a primary consumer is the larvae of chironomids, or a type of aquatic insect.
Three steps can explain cellular respiration: glycolysis, the TCA cycle (or citric acid cycle or Krebs cycle), and oxidative phosphorylation. Glycolysis is divided into two different stages: energy investment and energy payoff. During glycolysis, “ATP is both required and released at different stages” (Jordan & North 2013). The result is a net gain of two ATP, two NADH, and the production of two pyruvates. This process takes place in the cytoplasm. The pyruvates then go through the plasma membrane and into the mitochondrial matrix. During this pyruvate processing, NADH and CO2 are released and the pyruvates are converted into acetyl CoA. The acetyl CoA then goes through the TCA cycle, producing ATP, NADH, FADH2, and CO2. Finally, NADH and FADH2 go through the electron transport cha...
The digestive system otherwise known as the gastrointestinal tract (GI tract) is a long tube which runs from the mouth to the anus. It operates to break down the food we eat from large macromolecules such as starch, proteins and fats, which can’t be easily absorbed, into readily absorbable molecules such as glucose, fatty acids and amino acids. Once broken down, these molecules can cross the cells lining the small intestine, enter into the circulatory system and be transported around the body finally being used for energy, growth and repair.
This process may also be known as the Kreb’s Cycle, or the Tricarboxylic Acid Cycle (TCA). Coenzyme A and Acetyl CoA feed into the TCA cycle to power it. First, pyruvate is transported into the matrix by Pyruvate Dehydrogenase and precedes the TCA cycle. Coenzyme A forms the high-energy bonds with the organic acids, and acetyl CoA is formed by pyruvate dehydrogenase. The purpose of the TCA cycle is to metabolize Acetyl CoA and conserve energy produced in the forms of other coenzymes such as NADH and FADH2. During the Kreb’s Cycle, many phases occur and during each phase, new products are formed or released. From TCA-1 ot TCA-4, 2 NADH are formed and 2 CO2 are released. During TCA-5, ATP is formed, and during TCA-6, FADH2 is formed. Finally, during TCA-8, NADH is formed and OAA is regenerated. The total numbers of products per acetyl CoA are: 2 CO2, 3 NADH, 1 FADH2, and 1 ATP. The numbers of products per glucose are: 4 CO2, 6 NADH, 2 FADH2, and 2 ATP. Specific enzymes exist for this process as well. First, Acetyl CoA is changed to Citrate by Citrate Synthase, then Citrate is changed to Isocitrate by Aconitase. Isocitrate is changed to α-Ketoglutarate by Isocitrate Dehydrogenase, and α-Ketoglutarate is changed to Succinyl CoA by α-Ketoglutarate Dehydrogenase. Succinyl CoA is changed to Succinate by Succinyl CoA Synthase, and Succinate is changed to Fumarate by Succinate Dehydrogenase. Fumarate is then changed to Malate by Fumarate Hydratase, and finally, Fumarate is changed Oxaloacetate by Malate Dehydrogenase. Although Acetyl CoA and glucose may feed into this process, most energy comes from the coenzymes. Oxidative Phosphorylation takes place after the Kreb’s Cycle. This process occurs within the inner membrane of the mitochondria. Oxidative phosphorylation creates a concentration gradient that requires energy to push all the
In metabolism, complex molecules are degraded into simpler products including amino acids, glucose, and fatty acids. These simpler molecules can subsequently be broken down into the Acetyl CoA intermediate (Voet, D., Voet, J., Pratt, C. 2006. p. 397). Acetyl CoA then enters the citric acid cycle (TCA cycle), and is oxidized into carbon dioxide, CO2. During the TCA cycle, NAD+ and FADH are reduced to produce high transfer potential electrons, NADH and FADH2. These NADH and FADH2 molecules are oxidized during oxidation phosphorylation and the electron transport chain and generate water, H2O and ATP (Voet et al. 2006. p. 397).
Imagine you are eating a sandwich containing wheat bread, ham, lettuce, and Swiss cheese. Do you ever wonder where the nutrients go from all of the previous listed ingredients? Well, when a bite of this sandwich is taken, the mouth produces a saliva enzyme called amylase. This enzyme immediately goes to work by breaking down the carbohydrates that are in the bread. Once, the bite is completely chewed, the contents then are swallowed and go down the esophagus and begin to head towards the upper esophageal sphincter and the is involuntarily pushed towards the stomach. The next passage for the sandwich is to go through the lower esophageal sphincter; which transports the sandwich into the stomach.
...nzymes to digest them. In chemical digestion, hydrolysis breaks the bonds between monomers with the aid of enzymes, secreted throughout the digestive tract and by the accessory organs, to catalyze the process. These enzymes functional optimally in certain areas of the alimentary canal based on the pH of the surroundings. The monomers of carbohydrates and proteins are then absorbed into the mucosal cells of the microvilli lining the small intestine and diffuse into the capillaries surrounding the villi where they are transported in the bloodstream to cells in the body. Most of the nutrient absorption occurs in the duodenum and jejunum (University of Illinois Chicago, 2004). Lipids are too large to diffuse into the capillaries and are reassembled into triglycerides and enter the lymphatic system. Any undigested matter is eliminated from the digestive system as feces.
During digestion, the body breaks down food into smaller molecules that could then be used by the body’s cells and tissues in order to perform functions. This starts off in the mouth with the physical movements of chewing and the chemical breakdown by saliva. Enzymes in the stomach break food down further after traveling from the mouth through the esophagus. The food from here then moves into the small intestine, where pancreatic juices and enzymes dissolve proteins, carbohydrates, and fibers, and bile from the liver breaks down fats into these small molecules. Any portion of the fibers or food that were unable to be broken down are passed from the small intestine to the large intestine, which is where the digestive tract transitions into the excretory tract, then the colon and out of the rectum. Any liquids that have been stripped of their nutrients by the body proceed from the stomach to the kidneys. In the kidneys, sodium ions (Na+), uric acid, and urea are exchanged with water, which moves urinary bladder and is excreted through the
For people with no problems the intestines and stomach digest the carbohydrates that we take in into glucose, which is the body’s main source of energy. After we digest our food the glucose moves to the bloodstream. To get the glucose out of your blood and into the cells of your body the pancreas makes a hormone called insulin (Mayo Clinic, 2010). When you have gestational diabetes either your body does not make enough insulin during your pregna...
Food are also essential to all species that categorises them amongst three groups of nutrients they eat, thus making it easier for scientists to group species. Animals can be carnivores which enables them to obtain calories and energy by eating meat, such as, wolves. Herbivore organisms eat plants as their source of energy and nutrients, for example, horses. Omnivores are a collective group of animals that receive energy from both plants and animals, for example, chickens. Therefore different living things are exposed to hunting for different types of food (Burchill,
Producers are one, if not the most important role in a ecosystem since they are in charge of producing biomass from inorganic compounds(1). Some unicellular organisms like bacteria can be producers but most producers are plants which feeds some organisms and start the life cycle. Most of the producers start the cycle by performing photosynthesis. Lastly, consumers are animals which lack of ability to generate their own food, therefore they rely on other organisms to live (1). Consumers in the majority are in the top of the food chain examples of them are lions, tigers, and sharks. This animals are predators, animals who hunt other animals for food. Predation in some cases can be considered parasitism since sometimes the death rate is higher than the birth rate. When resources are scarce competition is present in the ecosystem and competition between the same specie happens when resource are extremely limited
Plantlike protists are called algae. They are plantlike because the make their own food through photosynthesis. Some consume other organisms while others are parasites when light is unavailable for photosynthesis. The groups of plantlike protists include the following: euglenoids, diatoms, dinoflagellates, green algae, red algae, brown algae, yellow-green algae, and golden-brown algae.
The human digestion system is very complex. It starts with the mouth, salivary glands, pharynx, esophagus, stomach, liver, pancreas, gallbladder, small intestine, large intestine, then ends/exits with the anus. Each step is essential to the whole system. For example, the mouth chews food and mixes it with saliva produced by the salivary glands, and then the pharynx swallows chewed food mixed with saliva, this is followed by the food traveling through the esophagus to the stomach where the food gets a bath and mixes with acids and enzymes. After the stomach, the liver, pancreas, and gallbladder produce, stores, and releases bile and bicarbonates. Bile is produced in the liver and aids in digestion and absorption of fat while the gallbladder stores bile and releases it into the small intestine when needed. Following the process into the small intestine, this is where nutrients will be absorbed into the blood or lymph (most digestion occurs here). Next is the large intestine this is where water and some vitamins and minerals are absorbed. Finally, it is the end of the road, the anus. At...
Aerobic Glycolysis: It occurs when there is plenty of oxygen. Pyruvate is the final product along with the production of Eight ATP molecules [Romano, AH; Conway, T (1996)].