ashorey's blog

EKGs, also called ECGs by American spelling, are vital tests that reveal detailed information about the cardiac functions and electrical impulses in the heart. An ECG can be obtained through a four lead measuring of the body. A  twelve lead gage is most commonly used for advanced heart health determination, but will show nearly the same information as a four lead gage when the V2 path is used, that is the leads from the right shoulder to the lower right side are used in the bipolar lead reading. This measures the electrical activity of the heart and displays it as a precise series of waves in a line. This represents the electrocardiogram. The reading consists of a small P wave, a QRS complex wave, and T and U waves. The P wave signifies the contraction of the atrium, that is the electrical impulse running down the arita that cause muscle contraction. The QRS complex is the hyperpolarization of the ventricle followed by the contraction repolerization, and relaxation. Next follows the T wave and the U waves, which are highly variable segments between each patient and hold much less information. The T and U waves can vary greatly and have little to no effect on the health of the heart and its functions as these are simply resetting polarizations in preparation for the next heart beat. 

The TYRP1 gene in Canis Lupus Familiarus, known commonly as the domesticated dog species, has been well studied. Since the genes of dogs have been sequenced and thousands of alleles compared, it was revealed that this gene, TYRP1, contains a very common and highly conserved mutation. The wildtype DNA sequence for the gene contains a segment 5'-TGGGGGAA-3'. In the mutation the sequence is simply 5'-TGGAA-3'. This shows a three nucleotide deletion that removes a set of three Gs. The reason this mutation is able to be so conserved is because three nucleotides form one single codon, allowing for the deletion to not cause a frame shift in the gene so that only one single amino acid is missing and the remaining correct amino acids are conserved. This mutation causes a disfunctional protein that acts as an enzyme in melanocyte cells that produce colored pigment in the dog hairs. Without a functional TYRP1, a brown pigment cannot be transformed into a black pigment. Because this defect has no toxicity in the accumulation of the brown pigment, the mutation was never selected against and gained frequency in population, also thanks to breeding. 

When cells lose water, many problems arise. Cellular membranes are made of a lipid bilayer that is extremely hydrophobic. This membrane requires the presence of water to stay together because the polarity surrounding the lipids keeps their organization favored by entropy and forces all the hydrophobic tails together. When water loss occurs, the cell membranes disintegrate, among other problems that arise. One mechanism in nature that exists to prevent this during periods of drought in plants. In order to prevent these effects, the plant cells produce a molecule that performs that same function that water was serving. These clever molecules are simple sugars that have hydrophilic properties and are able to keep cell membranes together and working correctly. These sugars include sucrose, raffinose, stachyose and trehalose. It has been found that these same sugars are able to prevent protein aggregation with water loss as well. These sugars can also be added in excess to cells to allow researchers to freeze down cells for later use over very long periods of time, for example 50 years. 

Plants, unlike many other organisms, are broadly and nearly uniformly able to survive extreme drought for long periods of time call desiccation. Desiccation tollerance is a characteristic that practically all species of plant have, although it may depend on the stage in the life cycle of the individual. Desiccation is thought to be an unfavorable process in total because plants that must endure constant drying out and rehydrating must make up for all nightly respiration with a short period of photosynthesis in the daytime prior to full day heat and light that causes water loss. This means that if the photosynthetic gains do not out weight the nightly repiration losses, then a net loss of energy occurs and cannot be sustained. 

Nitrogen is one of the most important elements found in fertilizers for plant growth because it is often that soil may be lacking it. When nitrogen is added to soil outdoors, it becomes a part of the complex nitrogen cycle that passes through life on earth. The nitrogen cycle may begin with gaseous nitrogen in the atmosphere. Often unnoticed, nitrogen is at a high concentration in the air we breathe compared to oxygen. The atmospheric nitrogen is in its diatomic form, N2. From here, nitrogen can be deposited by lightning or it is fixed by nitrogen-fixing bacteria and microbes in the soil that turn it into nitrates and ammonium. The ammonium can be made into nitrites by other nitrifying bacteria. From there, plants take up the nitrates and use it in chemical processes and in different molecules. The nitrogen travels up the food chain and gets deposited by different organisms back into the soil by waste products or by decay and decomposition. The decomposers then transform the nitrates back into ammonium in the soil. Denitrifying bacteria then transform nitrates back into atmospheric nitrogen when oxygen levels are low, reducing the mitrogen in the soil and increasing the nitrogen in the atmosphere. The cycle then repeats. 

 There are many elements vital to sustaining life. These elements, like energy itself, and not created or destroyed, but transfered from form to form and travel through cycles in the environment. Such elements include phosphorus which cycles through forms and life and is used and wasted and restored over and over. The phosphorus cycle may start in the form of solid rocks and geological formations. The phosphorus is present in rocks in the chemical form of phosphates. The rock, deep underground, rises from plate movements and volcano activations can pump it into the air and then it settles on the ground surfaces. When the rock rises to the surface, the phosphorus is exposed to weather. Here, the phosphorus is weathered from the rocks by wind, rain, and other disturbances. The phosphorus is now dissolved in solution and can leach into soil or run off into water pools. From the soil, the phosphorus gets used by plants to form different molecules. These plants are consumed by primary consumers and the molecules travel up the food chain. Eventually, the phosphorus returns to the soil by decomposers like fungi and certain bacteria. In cases of high run off, the phosphorus leaches out of the soil into the water pools. Here the phosphorus settles to the bottom and eventually forms new sediments and compresses down into rocks and other formations as phosphates once again. 

On Earth, water has a very important role in cycling through different forms and uses to be brought to all forms of life and help sustain them. The water cycles may begin as water in the oceans and largest fresh water sources. These are stores of water reserves, pools, from which most water leaves and returns to. The water here is evaporated up into the atmosphere by the solar rays that eject molecules from the surfaces of the water. The vapor is carried up because of its low density travels up into the atmosphere. The vapors are carried by the wind and coriolis effect across countries. Certain elevations can capture the clouds and force them into valleys. Here it hits cold air and can no longer maintain the energy to stay as a gaseous molecule so it condenses into water droplettes that hang in the high atmosphere. When enough water drops condense the gravity becomes to much and it falls back down to the ground in various forms of precipitation. The water then soaks into the earth and is used by different organisms: plants suck it up and it evaporates out the leaves, aquatic organisms swim in it and breathe oxygen through it, birds and small critters drink it off of leaves, etc. Eventually, the water runs down elevation in creeks and streams and through the soil until it finds itself back into a pool where the cycle once again takes place. 

Alzheimer's disease is a very impactful disease that has been extensively researched because of its dramatic effects on those with it and its high virulancy. Even then, research is ongoing and continuously discovering more. The beta amyloid accumulation in neurons of alzheimers patients shows to cause neurological dysfunctions that may be attributed to the disease, although the symptoms may also be due to mitochondrial errors. the function of the mitochondria relies heavily on its interactions with other organelles in the cell. Mitochondria–ER contacts are used for mitochondria and ER to share membrane bound proteins. An experiment with dysfunctional amyloid betas was done and it found swelling in the eR and mitochondria issues in the test subjects. This mechanism could be driving some of the Alzheimer's symptoms from over accumulation or not working amyloids.