Hey guys,,
Could someone have a look at this essay and give me a possible grade bc my bio teacher doesnt really have the right idea on the essay and what we actually have to do for it.
Tyy xoxo
Synaptic transmission is stimulated once an action potential arrives at the pre- synaptic membrane, causing the membrane to become depolarized which allows the calcium ions to diffuse into the pre- synapse, causing the vesicle neurotransmitter acetylcholine to be released from the pre-synapse and diffuse down the synaptic cleft to the receptors on the post – synapse. The neurotransmitter will bind to the complementary receptors, sodium ion channels will open and allow an influx of sodium ions to diffuse into the post synaptic membrane. This will cause a wave of depolarization at the post synapse, and once a threshold has been reached, will allow the electrical impulse to travel to the motor neuron, and across the nodes of Ranvier to be transmitted to the next neuron. This shows the importance of diffusion as it is the diffusion of the sodium ions in the post synaptic membrane which allows the membrane to become depolarized, and therefore allow the action potential to be transmitted to the next motor neuron, which it can then be used to stimulate muscle contraction. If the diffusion process did not occur, the sodium would not enter the post- synaptic neuron, so the electrical transmission would not be transmitted to the next motor neuron, so muscle contraction could not occur so organisms would not be able to defend themselves.
Control of blood water potential is vital for sustaining respiration and preventing high blood pressure, which is done through regulation of glucose levels. When blood levels increase, this stimulates the islets of Langerhans within the pancreases to secrete the hormone insulin. The function of insulin works by binding to complementary receptors on the liver target cells and increases the permeability of the cells by increasing the number of channel proteins on the surface. This allows the glucose molecules to diffuse into the target cells from high concentrations to low, meaning that because of the diffusion process, the blood waterpotential can be reduced. This shows that diffusion is importance because if the blood water potential is lower than inside the cell, water will move out of the cell via osmosis causing it to shrivel, leading to cell death. As well as this, the diffusion means that many glucose molecules can be storage as glycogen, which will be converted into glucose during respiration to generate ATP, which is key for phosphorylating molecules making them more reactive to complete metabolic process.
Exchange of gases between organisms is vital for attaining nutrients such as oxygen needed for vital metabolic processes such as respiration, and in humans is done through the raspatory system. When inspiration takes place, air will travel from a high to low air pressure trough the mouth, trachea, bronchi, bronchioles and to the alveoli. The alveoli is specialized for gas exchanges as it has a thin surface to reduce the diffusion path way, surrounded by capillaries which maintains a reduced diffusion pathway, as well as the presence on may alveoli to increase the surface area for uptake of substances. The oxygen will diffuse in to the alveoli, and through the alveoli endothelium, a thin surface which allows for maximum diffusion of gases into the blood stream. This highlights the importance of diffusion due to allowing oxygen to enter the mass transport system, as well as carbon dioxide to exit the body. If the diffusion of molecules did not occur, then there would be no oxygen in body cells, and during aerobic respiration oxygen is the final electron acceptor, so the electrons from the electrons carriers would not be able to diffuse down ATP synthase so no ATP molecule would be made. As well as this, if diffusion did not occur there would be a high concentration of carbon dioxide in the blood, which will change the PH of the blood, leading to a change in tertiary structure for hemoglobin, and the hemoglobin will not be able to associate with oxygen, there for reducing aerobic respiration and increasing anaerobic.
In the ileum wall, diffusion of sodium allows glucose to be cotransporter into the epithelial cell against its concentration gradients, causing an increase in glucose concentration within the epithelial. The decreased concentration of the sodium ions allows a concentration gradient to be generated, and this shows the importance of diffusion as it allows the glucose to be co- transported into the cell. Within the epithelia cell the high concentration of glucose allows it to diffuse into the blood stream and allows it to create a concentration gradient within the bloodstream, so more glucose can be absorbed into cells. Glucose is vital for respiration so this diffusion allows glucose to be transported to the cells, where it will be used during respiration to generate ATP, which have energy that can be release instantly, there for energy can be quickly acquired for active transport of molecules on phospholipid membranes using carrier proteins. If diffusion did not happen, the sodium would not diffuse into the epithelia cell, so glucose could not be cotransporter against its concentration gradient, so there would be less glucose available for respiration. The less respiration, the less ATP there is available for active transport of molecules, so sodium would not be able to leave the epithelia cell and creates a high concentration of sodium with epithelia cell, so furthermore no glucose could be cotransporter.
Within photosynthesis, the Calvin cycle is a vital part for generating organic substances used for maintaining biomass and for respiration. In the cycle, carbon dioxide diffuses into the stroma of the chloroplast, and is used in a condensation with RuBp using the enzyme rubisco to produce 2 GP molecules. The GP molecules are reduced by NADP into 2 TP molecules, and 1 of the carbons from the TP molecules is used to generate an organic substance. This shows the importance of the diffusion of carbon dioxide in order to be combined with Rub in order to create the organic substance used by plants. If the diffusion of carbon dioxide did not occur, then there would be no organic substance to be used for biomass and growth, as well as for respiration to provide ATP for active transport of protons in mass transport to deliver sucrose the sieve tube element.