The partial pressure (tension) of O2 in water and fish blood is the same (0.2 atm), however, the partial pressure of O2 in the swim bladder is much greater (at 500 m, 40 atm). Fish can secrete O2 in the swim bladder against a pressure gradient and keep it by a rete mirabile (“miracle net”). The tension of O2 in the venous capillaries leaving the bladder is equal to the one in the bladder (high). O2 starts go away, but the arterial capillaries surrounding the venous capillaries catch the leaving O2 (arterial capillaries contain blood with a lower O2 tension going in the opposite direction; countercurrent exchange occurs). The arterial blood carries the O2 back to the swim bladder.
You are here
The title of this scientific news article drew my attention immediately. I thought to myself, “how could having a dog possibly help my immune system?” I always speculated that exposure to things such as animals that could possibly carry dirt, infection and germs would only heighten allergies or affect the immune system negatively. However, according to this research, it is about the exact opposite. I think I was attracted to this article because I personally have dog at home and I was eager to learn what exactly lies in dogs that can possibly help humans health. I am curious to find out if the microbe L.johnsonii is found in allergy medicine such as zyrtec or allegra or if there is any more studies that help prove that this microbe does in fact prevent allergies. The article does mention toward the end that L.johnsonii is still being researched and used in experimentation to further discover the benefits and I am hopeful that I will be seeing this microbe in the near future for other uses!
Isopentanol (1.196 mL, 10.99 mmol) and acetic acid (0.743 mL, 12.99 mmol) of acetic acid were added to a 5 mL round-bottom flask. Next, sulfuric acid (4 drops) was added to the flask and was mixed prior to reflux. The solution was refluxed for a total of 45 minutes and the organic layer that accumulated in the side arm was tipped back into the flask at 15-minute intervals. The product was transferred to a new tube and the organic layer was extracted in water (1 mL, 55.51 mmol). The remaining organic layer was further extracted using sodium bicarbonate (1 mL, 26.19 mmol), followed by sodium chloride (1 mL, 36.96 mmol). Anhydrous was used to remove any remaining inorganic material left in the tube. The resulting product after extraction, crude ester, was weighed and transferred into a clean, dry vial. The odors of the reagents and the products at each stage of the experiment were noted and the product was analyzed via IR spectroscopy.
Trimyristin is an organic compound found in nutmeg, whose structure consists of a glycerol backbone and fatty acid groups. In this lab, pure trimyristin was extracted from nutmeg via filtration and recrystallization using acetone as the solvent; acetone also helped to purify the sample along the way. Trimyristin undergoes an acid- catalyzed hydrolysis reaction with HCl to form a carboxylic acid (myristic acid). The percent recovery of crude yellow trimyristin, or in other words, the amount of trimyristin (per gram) of nutmeg as a percentage was found to be 65%. After the first recrystallization, the percent recovery decreased significantly to 22.5%. Some possible sources of error for this drastic decrease in percent recovery include cooling the solution to quickly instead of properly letting it cool to room temperature before placing it onto the ice bath. In addition, the compound may also have not completely dissolved which would result in a decreased number of crystals formed. Following the second recrystallization of the trimyristin, the remaining nutmeg used resulted in a percent recovery of 68.88%. The precipitate formed from the hydrolysis was myristic acid and its percent recovery was calculated to be 75%. The purity and identity of both products were assessed using their melting point ranges.
In this experiment, the SN2 Williamson-Ether Reaction of 2-naphthol (using NaOH, EtOH, and n-Butyl iodide as solvents) was used to produce butyl naphthyl ether. The oxygen in NaOH was used as a source of electrons to deprotonate the alcohol group on 2-naphthol to form the sodium naphthoxide ion. This reaction proceeded as the solution was initially refluxed. Next, n-butyl iodide was added to the RBF and was “attacked” by the negatively charged oxygen on the naphthoxide ion as a second reflux proceeded. This reaction could occur because iodide is a good leaving group- the naphthoxide ion “attacked” the carbon adjacent to iodide. This is an SN2 reaction because the naphthoxide ion (the nucleophile) attacks the carbon adjacent to the iodide (the electrophile) at the same time as the iodide leaves. This reaction produced butyl naphthyl ether and sodium iodide.
In the event where a retrovirus is killing domestic dogs and only one breed can be saved, it is important to save a breed that has more roles other than a being a house pet. A German Shepard and her puppies should be saved because intelligence, strength and role in society. Originally German Shepherds were established specifically as working dogs. They were bred to preserve traits that made them excellent sheep herders and protectors. They have a keen sense of smell, are very intelligent and have great speed and strength, which separates them from most dogs. They have the ability to learn simple tasks only after five repetitions. They can interpret instructions better than any other large breed making them perfect as police, guard and search and rescue dogs. Their keen sense of smell makes them the most widely used dog in a variety of scent-work roles. Cadaver searching, narcotics detection, explosive detection, and mine detection are just some of the reasons why German Shepherds are very important to have in our society. Without them our society would face many setbacks as well as affecting the safety of human lives.
Glycogen is a group of glucose molecules that is mainly stored in the liver and muscle cells. The liver regulates blood glucose levels and the break down of glucose provides energy (ATP) for muscle contractions. Glycogen has a branching structure that is optimized for efficient storage and release of glucose. The branching allows for many ends to add to and remove from. Glycogenin is a complex structure in the middle of this branching structure and serves as the core to which the braches are anchored to.
The purpose of this lab is to use fractional distillation to synthesize cyclohexene through the acid-catalyzed dehydration of cyclohexanol with 85% phosphoric acid. A gas chromatography (GC) was used to determine the purity of the distilled cyclohexene and the number of compounds present. Additionally, and infrared spectrum (IR) was used to determine if an alkene was present by viewing frequencies of light absorbance. Furthermore, a color test was preformed using 3% bromine in dichloromethane and an aqueous solution of 1% potassium permanganate and 10% sulfuric acid to determine if an alkene functional group is present.
Data examining the relationships between hours slept and GPA for students living on the island Enies Lobby. Scatterplots showed low correlation, however the line graphs display a similarity between Male and Female students, on top of a trend of more hours of sleep leading to a higher GPA.
This experiment aims to demonstrate principles of conditioning by blowing a puff of air at a planarian and measuring their response, which consist of a contraction followed by an extension. The methods include puffing 30 seconds of air every 45 seconds at the planarian 50 times. The planarians response will take about 1 second. You must place the planarian into a conditioning trough and let it adapt to the environment for 5-10 minutes. Pull back the syringe to 30 cc and blow a puff of air onto the head region of the planarian. Use a timer to measure the time between air puffs and record the data using (+) if the animal contracted, (-) if the animal did not, and (T) if the animal turned and swan the other direction. As a second experiment, you condition the planarians to minimize the amount of times they turn in the opposite direction by continuing the number of air puffs until the turning decreases.
The second article describes planarians and their habits. They are slimy flatworms that prey on earthworms, slugs, snails and soil arthropods. The slimy appearance is from mucus secretion that helps them keep their body moist as well as movement. They prefer the dark, cool temperatures and require high humidity because they die quickly if it looses 45% of its body moisture. This is why with the rain come land planarians because it increases the humidity and allows planarians to come to the soil.
Faber B. With the Rain Come Land Planaria. 2015 Nov 30 [accessed 2017 Oct 20]. http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=19531
Can Planaria Learn. [accessed 2017 Oct 20]. https://biology.mit.edu/sites/default/files/Learning%20and%20Memory.pdf