Writing in Biology

Effects of Caffeine on Metabolism

A study was conducted in which mice were given a diet of normal food, while other mice were given a caffeinated diet. It was found that caffeine significantly decreased the mass of fat tissues, as well as increasing the transformation of ADP to ATP while all other variables were kept the same. It was concluded that caffeine promotes lipid metabolism via the cAMP pathway.

Resource: Zhang, S., Li, Y., Wang, G., Tan, R., Tsoi, B., Mao, G., . . . He, R. (2015). Caffeine ameliorates high energy diet-induced hepatic steatosis: Sirtuin 3 acts as a bridge in the lipid metabolism pathway. Food Funct., 6(8), 2578-2587.

A study was conducted on ten taekwondo athletes, in which athletes were given either a capsule containing caffeine or a placebo one hour before the combat simulation. It was found that while the caffeine didn’t have any measurable effects on the perceived exertion of the athletes, it was estimated to have increased glycolytic contribution during combat simulation.

Resource: Lopes-Silva, J. P., Santos, J. F., Branco, B. H., Abad, C. C., Oliveira, L. F., Loturco, I., & Franchini, E. (2015). Caffeine Ingestion Increases Estimated Glycolytic Metabolism during Taekwondo Combat Simulation but Does Not Improve Performance or Parasympathetic Reactivation.

The flower I photographed was the Hibiscus rosa-sinensis Malvaceae, commonly known as the “Snow Queen.” This flower is commonly found in Asia such as China. The flower is edible and can be found in salads, along with other uses such as hair care. The flower can be a pH indicator, in acidic solutions the flower turns a deep purple and in basic solutions the flower changes to green. In China, the flower is used for medicine and skin care.  The flower is grown in tropics or subtropics because it cannot survive in temperatures below 10^oC (50^oF). 

In the article, Movement Intention After Parietal Cortex, the hypothesis that is discussed is whether or not direct stimulation of either the parietal or premotor cortex in the brain would result in direct movement of different regions of the body. The study was conducted by using seven human patients that either had a tumor in anterior or posterior of the central sulcus. In order to find specific sites for stimulation, an MRI was used to find 57 sites. Patients were under local anesthesia and as specific regions were stimulated the patients were asked whether they felt something or moved a body part. The results of the study showed that premotor cortex stimulation resulted in movement while parietal stimulation resulted in the intentions of movement. At higher intensity of stimulation the parietal stimulation lead to the patients believing the movement was accomplished. Overall, the study showed that before people perform a movement there in an intention of conscious movement in the parietal. 

In the article, Movement Intention After Parietal Cortex, the hypothesis that is discussed is whether or not the direct stimulation of either the parietal or premotor cortex would cause direct movement of other regions of the body. The study was conducted by using seven human patients that either had anterior or posterior tumors of the central sulcus. In order to find specific sites for stimulation, an MRI was used to find a significant amount of localized sites. Patients were under local anesthesia and as the specific regions were stimulated the patients were asked whether they felt something or moved a body part. The results of the study showed that premotor stimulation resulted in movement while parietal stimulation resulted in the intentions of movement. At higher intensity of stimulation the parietal stimulation lead to the patients believing the movement was accomplished. Overall the study showed that before people perform a movement there in an intention of conscious movement in the parietal. 

The beak depth had the best value of 14 mm and an intermediate value of selection strength. It only took about 20 years for the beak depth to reach the best value of 14 mm. The beak width had a low selection strength compared to beak depth, the result lead to the beak width taking longer to get to its best value. Although both beak depth and width would reach its best best value. At 104 years the average beak depth was 14,2 mm and the average beak width was 6.89mm. 

Mutation rate is an important parameter to obtain a bimodal distribution because a higher mutation rate allows for finches on each side of the mountain to mutate so that there are varying beak sizes without a mutation rate then on each side of the mountain there would be a fixed beak side, and for genes to be lost but random mutation allows for alleles to be present in the populations. Mate selectivity and mate distance are two important parameters to obtain and maintain a bimodal distribution. A larger mate distance caused a bell curve therefore indicating that a finch’s beak size is influenced by the distance of mating. Also a higher mate selectivity showed that the beak size is influenced by how finches mate with other finches with similar looking traits. When these two parameters work together there is a greater selection of beak sizes.  

I predict that Biome 2 is most similar to the data of the Temperate Evergreen Forest climate diagrams. I base this prediction on that there climate diagrams are similar. Although not exactly the same both Biome 2 and Temperate Evergreen Forest have around the same annual precipitation with Biome 2 having 691mm and the Temperate Evergreen Forest having 672mm. The average annual temperature for the Temperate Evergreen Forest is 17.5 ^oC, while the average annual temperature for Biome 2 is 19.5^oC. I believe the data of Biome 2 is from the part of the Temperate Evergreen Forest that is located between 45^o and 50^o, also known as “the temperate rainforests.” Although all Temperate Evergreen Forests are found between 30^o and 50^o N/S.   

I predict that Biome 1 is most similar to the Temperate Deciduous Forest. I base my prediction off the fact that both climate diagrams are similar in both Temperature and Precipitation. The Temperate Deciduous Forests can have 500mm-2500mm of rainfall annually, which is what led me to the conclusion that Biome 1 was the Temperate Deciduous Forest. Along with the Temperatures going below freezing at certain months. The average annual temperate for Temperate Deciduous Forests are 7.6^oC, while Biome 1 has an average annual temperature of 9^oC.  The latitude Biome 1 would be in is 30^o to 50^oN. In the Temperate Deciduous Forests needs the amount of rainfall seen in both climate diagrams to support tree growth. 

Global warming is a multifaceted issues caused by an interconnected series of events, both anthropogenic and natural. Focusing on the anthropogenic side, global warming is something that can be traced back to the industrial revolution, when humans began burning coal and oil in large quantities to power newly created machinery. These sources of energy happened to be carbon sinks, which had previously sequestered carbon both underground and in forests for a span of time. With this carbon now out of its “locked up” form and being released, it travels into the air and builds up in the atmosphere. This carbon, largely in the form of CO¬2, interferes with the Earth’s natural process of reflecting solar radiation and heat back into space. Instead of hitting the Earth’s surface, reflecting off, and being sent back into space, the CO2 absorbs the energy after it is reflected off of the Earth, keeping this energy and heat in our atmospheric system, and warming the Earth in the process. This is called the Greenhouse Effect, as the heat becomes trapped inside much like a greenhouse.