The lateral motion data suggests that mako sharks are kinematically closer to tuna than other sharks. As supported by sonomicrometry recordings, during active swimming mako sharks detach their red muscles from the neighbouring tissues and focus their motion towards the posterior region of their body. Such mechanism has been found to be reciprocal in tunas, which recruit their deep red muscles in a similar fashion to power their caudal region. Nonetheless, mako sharks rely on their hypaxial lateral tendon for producing such movement, while in tuna the tendons that perform this task are found in the horizontal septum. Thus the researchers conclude that the locomotion systems of lamnid sharks and tunas arose independently by convergent evolution.
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Metabolic coupling is the process of using energy that is released from an exergonic pathway to provide energy needed for an endergonic pathway. The main goal of metabolic coupling is to end with a negative change in free energy (delta G). A negative change in free energy indicates a spontaneous reaction. Metabolic coupling can exist in three forms: between biochemical pathways, within biochemical pathways and within chemical reactions. Energy transfer within metabolic pathways involves the removal of phosphate groups through hydrolysis, thus resulting in a large negative free energy value. The amount of free energy available in the bond is called the phosphoryl group transfer potential. Phosphorylation is the reverse reaction of adding phosphate groups through the input of energy (ATP).
After allowing four days to elapse, all the data pertaining to the post-experiment web mass was collected. Values were compared to the original data collected for web mass. We observed that the condition with the lowest amount of web mass at the conclusion of the experiment was the cold condition. Furthermore, the warm and control conditions did not vary significantly in terms of the amount of web mass. The observation of the cold condition resulting in the lowest amount of web production had some confounding variables. Mainly, one of the spiders escaped its enclosure on the third day of the experiment. This would certainly lead to less web production since the spider was not present to produce web on the final day of the experiment. In addition, the ice replacement was relatively inconsistent due to time constraints. However, the other three spiders completed the entire experiment and the effect was still observed among those three.
Vitamin D is indicated to be lacking in my diet, for the target of 15 micrograms is not met for I only consume about 3 micrograms on average. Not getting enough vitamin D can be dangerous for it plays the role of modulating cell growth, neuromuscular and immune functions, absorption of calcium, therefore, contributing to bone growth. Deficiency not very uncommon because vitamin D is naturally not present in many foods, making it more important that we are aware of our intakes8. Given that we are entering the colder months it also is more challenging to obtain vitamin D from the sun, therefore it must be done by selecting proper foods. As mentioned before, fat-soluble vitamins are more likely to cause toxicity for it is stored in the body, therefore monitoring the intake of this vitamin is extremely important. In most extreme cases toxicity may raise blood levels of calcium, in turn leading to damage to the heart, blood vessels and kidneys8. Some of the best sources of Vitamin D are fatty fish, including salmon and tuna, both of which are foods I enjoy and will add to my diet in greater amounts to make up for the lack of Vitamin D in my diet. Beef liver, cheese, and egg yolks also contain some amounts of vitamin D.
A new study published by the medical journal Science Translational Medicine discovered that there could be a correlation between Parkinson’s disease and the Appendix. The research discovered that the people whose appendix were removed had less chances of getting a neurodegenerative disease. The Appendix, an organ whose function still unknown, it also proved to be a reservoir of the substance that kills brain cells. There is a link because in Parkinson’s disease, toxics proteins accumulate in the brain and kill nerves, especially those linked to movement. Although it may seem counterintuitive, there is growing evidence that the digestive system has a link to the disease. The analysis revealed that the risk of developing Parkinson’s disease was 20% lower in people who had had their appendix removed. However, the search for the origin of Parkinson’s still can’t answer why the disease appears in some people and not in others.
DCPIP accepts electrons after they leave Photosystem II, but before they go to Photosystem I. Both photosystems are a part of the light-dependent reaction, which means that sunlight fuels their pathways. Photosystem II hydrolyzes water and pushes two electrons further into the electron transport chain. Instead of moving on to Photosystem I, DCPIP accepts these electrons. Without light, no electrons are pushed through the chain and therefore, DCPIP stays darker blue in color. If there are more chloroplasts exposed to light, there would be more electrons for DCPIP to accept, making it more clear in color. This relates to our prediction because if Kale does have more chloroplasts like we expect, then the absorbance of light should be lower.
Both songbirds and humans are primed towards learning their species vocalizations and filter out the rest of sounds during the learning process. They both go through a critical learning period or sensitive period, during which information is stored for use in later stages of learning. Oscines also have a subsong period which is analogous to infant babbling and connects the perceptual and sensorimotor stages of vocal learning. Finally, there is a crystallization period, during which plastic song or language is perfected into the standard vocalizations of the species.
As a group, we observed photos of warblers from the Setophega worksheet. To begin, a series of 12 common plumage characteristics for the warblers were identified. We choose to observe the presence of wing bars, if the bird had a short or long beak, the color of the throat, eye ring color, belly color, feet color, the presence of yellow feathers, the presence of bright colored feathers, rump coloration, the presence of a curved beak, if the bird had more than two feather colors, and if the crown was a different color than the body. We observed the photographs and the skin museum to observe each species and categorize the plumage characteristics. We wrote the color of each plumage feature in the table and we used “1” and “0” for traits that didn’t specify a color. The presence of wing bars, yellow feathers, bright colored feathers, more than two feather colors, and a matching crown were indicated by a 1 for yes and a 0 indicated no. A short beak was categorized by a 0 and a long beak was categorized by a 1. After evaluating each of the 33 species of Warblers for the set of characteristics determined, four of the patterns were chosen to apply to a phylogenetic tree. We choose the presence of wingbars, the presence of yellow feathers, foot coloration, and the presence of a matching crown color. We indicated the absence of wing bars with a black line on the taxa of the phylogenetic tree. On a new tree we indicated the absence of yellow feathers with a black line on the taxa of the phylogenetic tree. On another new tree, we marked the taxa of species that had a different color crown that the rest of the back with a black line. On a fourth tree, we indicated the color of the feet by using a different color line on each taxa that matches the color of the birds feet. Using the phylogenetic analysis, the characteristics were analyzed to determine any clear patterns of evolution and gene succession.
Years of industrialization and little to no regulation on what can be emitted into the atmosphere has led to a changing climate which will only grow worse with time. The current shared opinion among scientists is that humans need to limit the rise in temperature to only two degrees Celsius above preindustrial levels in order to avoid a point where the increase in temperature reaches a point where it would no longer be able to be controlled or averted. Currently, climate change is occurring because of the presence of “greenhouse” gases in the atmosphere, mostly methane and carbon dioxide. These gases act as a blanket of sorts for the earth and trap incoming radiation from the sun, thus heating the planet. This process drives other factors that then contribute to the increased temperatures as well. With the increase in temperature, glaciers and other land bound ice are melting and raising sea levels. This affects global temperature in two ways. The first is that the ice normally serves as a source of albedo that stops the sunlight from being absorbed by the darker colored earth and reflects it back into the atmosphere. The second is that as sea levels rise, it provides more water to absorb heat, again raising temperatures. These are just two examples of how climate change has the potential to reach a tipping point that, if reached, will not be able to be stopped.
Following up on my work on sensory priming during the past semester and this summer, I will continue running arena trials with a new generation of P. princeps in order to study the behavioral responses of jumping spiders towards visual and acoustic stimuli. My experiments consisted of introducing a jumping spider in an arena so that it walked into a viewing chamber were pictures suddenly appeared in an iPod screen. The pictures were of a wasp (a potential predator), a cricket (a preferred prey), and a beetle (a neutral stimulus). Each spider was shown one image per trial and during the sound trials a speaker played a wasp buzzing sound for 5 seconds every 2 minutes. Since the trials were run between the end of the Spring semester and this summer, it is possible that the effect of age influenced the spider’s response towards the stimuli, because jumping spiders are very visual and still they showed little response towards the pictures.