Digestion

Submitted by cslavin on Thu, 03/28/2019 - 13:35

The digestion of a cheeseburger starts in the mouth. The saliva contains enzymes, amylase and lipase, that begin to break down the food. Amylase starts to break down carbohydrates, and lipase begins to breakdown fats. The saliva moistens the food and begins to liquify it. The cheeseburger then would travel down the esophagus through peristalsis, which is a coordinated movement of food along the digestive tract. Once the cheeseburger enters the stomach, food is broken down by enzymes and segmentation, or food mixing. Cheif cells in the stomach secrete pepsiogen, which once it enters the stomach becomes pepsin. Pepsin breaks larger proteins into smaller pieces. Parietal cells secrete hydrochloric acid which denatures proteins. The food them travels into the small intestine where chemical digestion continues until completion. By the time the food enters the large intestine, its nutrients have fully been absorbed. The main function of the large intestine is compaction of waste and absorption of water. 

Mnemiopsis

Submitted by aprisby on Thu, 03/28/2019 - 13:06

Mnemiopsis (comb jelly) are species of jellyfish native to the Atlantic Coast that became an invasive species released into the Black Sea. At the time, the Black Sea was already facing problems due to increased inputs of nutrients. This process is called eutrophication, an increase in the nutrient content of an ecosystem. Mnemiopsis is a carnivore that feeds primarily on zooplankton. Mnemiopsis increased rapidly causing populations of zooplankton to decrease, phytoplankton to increase, oxygen concentrations to decrease, and fish to rapidly decrease. This is an example of how populations change. Populations can change from birth, death, immigration, and emigration. Population dynamics and fluctuations are how populations change in abundance overtime, and may rise and fall about the mean. In 1989, the population of comb jelly had reached the highest levels, causing a massive drop in populations of other species. This was an example of population outbreak which occurs when populations are exploding in numbers. Population cycles are alternating periods of high and low abundance occur after constant intervals of time. They may be caused by Internal factors (hormones or behavioral changes) or external factors (weather, food, predators).

Interstitial Organisms

Submitted by afeltrin on Thu, 03/28/2019 - 12:59

This article discusses the organisms that live in the space between the sand grains, which is referred to as the interstitium. Various metazoan taxa inhabit this area, including nematodes, copepods, and annelids. The main objective is to discuss the varying hypotheses that explain the origins of interstitial animals. The hypotheses include three scenarios: ancestral bilaterians were first to inhabit this area, the process of progenesis allowed for organisms to adapt to living in the interstitium, or that the body size of organisms would slowly decrease as time went on and lead to organisms coming to inhabit the area. The researchers provided an approach based on phylogenomics to create a likely phylogenetic tree of progenesis. The idea of an “Archiannelida” is rejected as a possible hypothesis. Hypotheses including progenesis are determined to be applicable, as the forefront feature of organisms that live in this environment is small body size. Adaptation over time for smaller body size is a key aspect pertaining to progenesis. Another imperative factor to consider is miniaturization, when looking into the potential history of these interstitial organisms.

Draft Background

Submitted by aprisby on Thu, 03/28/2019 - 12:41

Each group will use quantitative data already collected and available on the beak sizes and shapes of their two species. This will have been collected from the University of Massachusetts Amherst Ornithology collection of bird skins. We will collect and present the beak morphology through a chart [and pictures..?] for each group. They will then be able to draw their own conclusions. Additionally, we will use the database, the Cornell Lab of Ornithology, Birds of North America which provides an extensive range of information on each bird species in North America. It provides tabs on appearance, systematics, distribution, migration, habitat, diet and foraging, sounds, behaviors, populations, conservation, research, as well as tables on bird measurements. The database, South Dakota Birds, Birding, and Nature also provides an overview of bird species in North America.

 

Specific Aims PP

Submitted by rdigregorio on Thu, 03/28/2019 - 12:39

The specific aims of this experiment would be to determine how the depth of the seeds in the sand they are planted in effects the growth and development of the seedlings. To demonstrate this we will be planting the seeds from Silybum marianum at different depths in sand. Sand is the typical terrain these plants grow in. They will be buried at depths of 2, 4, 6, 8, and 10 centimeters respectively. There will be three seedlings planted at each depth so we can account for any outliers, and to make sure we get at least one to germinate. After being buried the seeds will be put into the morrill greenhouse so they can stay at a constant temperature. When the seeds finally sprout out of the sand we will measure their lengths and compare the differences between the different seeds depths. That way we will find out what the effect of depth is on the development of Silybum marianum seeds.  

 

Specific Aims

Submitted by rdigregorio on Thu, 03/28/2019 - 12:35

The specific aims of this experiment is to determine how the depth of the seeds in the sand they are planted in effects the growth and development of the seedlings. To demonstrate this we will be planting the seeds from Silybum marianum at different depths in sand. They will be buried at depths of 2, 4, 6, 8, and 10 centimeters respectively. There will be three seedlings planted at each depth so we can account for any outliers. After being buried the seeds will be put into the morrill greenhouse so they stay warm. When the seeds finally sprout out of the sand we will measure their lengths and compare the differences between the different seeds depths. That way we will find out what the effect of depth is on the development of Silybum marianum seeds.  

 

Ethogram Methods

Submitted by rdigregorio on Thu, 03/28/2019 - 12:29

To conduct a time budget analysis, the entire 48 minutes and 55 seconds of footage was scored using the seven behavioral categories obtained in part one. Three specific bouts of behavior were also chosen to be scored: a playful bout, a bucking bout, and a standing still bout. The playful bout would be scored every time the horse approached with head up, nipped at a foal, and trotted away in that sequence. The bucking bout was categorized by ears back, bucking, and running away. The standing still bout was scored when the foal would survey, stomp hoof at the ground, sniff, and then graze. In addition, modifiers were used to determine the context each behavior occurred in; 1 being the foal behavior when alone, 2 the foal behavior with the other foal, and 3 the foal behavior in all contexts. This determined the percentage of time the foals spent in each behavioral category.

 

Ethogram intro

Submitted by rdigregorio on Thu, 03/28/2019 - 12:27

Animal communication is the study of the methods of transferring information from a sender to a recipient in the context of certain environments. For years, researchers have studied communication amongst species to determine evolutionary relationships between animals. Horses in particular offer a unique perspective on animal communication methods due to the fact they are a species that has been domesticated for hundreds of years. Better understandings of horse behavior has been known to increase the overall care and health of the animal, while also improving our scope of knowledge for horse behaviors and how it is used to communicate.

 

Chem Lab Discussion

Submitted by rdigregorio on Thu, 03/28/2019 - 12:26

By analyzing the speed of the reactions performed and how the differences in temperature impacted them, we were able to conclude that the higher the temperature at which the reaction is conducted, the faster the reaction time, and the lower the activation energy. The previously calculated rate of the reaction helped us calculate K, and after converting the temperature to kelvin, we were able to graph the -Ea/R to show the activation energy. The increase in temperature would explain the decrease in activation energy because the higher the temperature, the lower the magnitude of the bond energy. This means that the bonds are more likely to break faster because they are weaker than they would be at cooler temperatures. This experiment was successful in explaining the connection between the temperature that a reaction is run at and the amount of activation energy needed to start the reaction.

 

Chem Lab Methods

Submitted by rdigregorio on Thu, 03/28/2019 - 12:26

After adding the solutions we tried our best to keep the temperatures constant as we timed the reaction. Once we noticed the color of each solution turn to a burnt yellow/orange color we concluded that the reaction was complete and stopped the timer. This data collected was our reaction time for the first trial. To get more accurate results, we performed the experiment again for 10℃, 20℃, and 30℃, and got the average reaction time at each temperature. With this information, we were able to calculate the rate of the reactions, which lead to determining the equilibrium constants, K, and eventually the slope of our observations and the activation energy.

 

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