72580
Rodriguez Silva
The Top-down Effects of Brine Shrimp on Algae
INTRODUCTION An ecosystem is a delicate structure moderated by the network of interactions between all of the organisms that inhabit it. These organisms can be arranged into trophic levels, forming a chain or pyramid in which energy flows from one level to another. In a top-down trophic cascade, the higher-leveled consumers regulate and dictate the biomass of the trophic levels below (Leroux and Loreau 2015). The removal or addition of these consumers would initiate major changes in the survivability and overall diversity of most of the other species in the ecosystem. The balance between populations is maintained through natural growth and decline, predation, and resource
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In a trophic system that is stable, most organisms are equally thriving, without any extreme stress or pressure to cause drastic population reduction as well as without limitless resources to allow unrestricted growth. A disturbance in the stability of a trophic system, or food web, could trigger a chain of reactions in which most, or sometimes all, of the trophic levels are affected. Some populations benefit from alterations in the system, but others suffer huge declines in numbers. Regarding consumer-driven effects, a change in consumer populations is often a product of immigration/emigration, development of prey adaptations against predators, as well as other biotic and abiotic factors, such as introduction of new species and weather (Evans 2011). In the case of an increase of a higher-leveled consumer, the trophic level directly below experiences intensified predation and rapid deterioration. The overpopulation of one species serves as an overwhelming pressure on other species that are either directly competing for resources or that serve as prey. In our experiment, we explore …show more content…
The brine shrimp were hatched from cysts in seawater and placed in jars, and the algae were contained in large flasks of seawater in various concentrations, for everyone to access. The number of brine shrimp were our independent variable and the algae concentration were our dependent variable. We obtained 6 clean jars for our group in which we created our miniature ecosystems. We labeled each jar with our group name, lab section number, and replicate number. After deciding on what algae concentration we wanted to hold constant in our jars, we calculated the volume of seawater and algae solution required to achieve the desired algae concentration of 50,000 cells/mL and a total volume of 50 mL (C1V1=C2V2). We measured out the required volume of seawater with a graduated cylinder, pouring the contents into each jar. Because our calculated seawater volume was not a whole number, we utilized a micropipette to transfer the remaining amount of seawater. We then proceeded to collect algae from the large flask after carefully swirling around the algae to evenly distribute it within the water (Flipped Lab Videos 2016a). Using the micropipette, we transferred the appropriate volume of algae to the jars. We collected a sample of brine shrimp and added them to petri dishes in order to view them underneath a dissection microscope. Because we were testing the top-down effects, we decided on having
Plankton Activity Postlab 1) Apply 2.5: Use mathematical and/or computational representations to support explanations of factors that affect carrying capacity of ecosystems at different scales. Explain how the abundance of phytoplankton in the pond depends on the abundance of an abiotic resource such as nitrogen. - Phytoplankton are the producers in the pond. Species of organisms in ecosystems have their own carrying capacity relative to other species, and carrying capacities are determined by particular abiotic and biotic resources in an ecosystem. An increase in nitrogen levels in the pond (e.g. from fertilizers) will result in a dramatic increase in phytoplankton levels, but once phytoplankton population reaches its carrying capacity (determined by availability of other resources besides nitrogen, [DO] levels, predation etc.),
For instance, forks accounted for 33% of the population while spoons accounted for 67% of the population---knives were once again extinct by the second generation (Table 2A). In the third generation, spoons accounted for 100% of the population (Table 2A). As for prey in the grass habitat, in the second generation, black beans accounted for 16.58% of the population while, green beans accounted for 27.69%, white beans accounted for 29.35% and pinto beans accounted for 26.37% of the population (Table 2B). In figures 4A and 4B, it is easier to note the changes in percent population since the three generations and the final percent of population (after the three generation) are
Using the 0.1 M stock solutions of sugar, a 0.01 M dilution was created for each sugar type by adding water to the stock solution 9 out of 1. A 20 mL dilution was made for each trial. The same volume of each solution (10 mL -5 mL ) was added to the green sponges to create four group; Group 1: Sponge with 10 Ml 0.01 M glucose solution, Group 2: Sponge with 10 mL 0.01 M fructose solution, Group 3: Sponge with 10mL 0.01 M sucrose solution, Group 4 (Control): Sponge with 10 mL water. The four sponges were placed every 90 degrees on the edge of the arena. The isopods were placed into their environment for one to two minutes to acclimate with the environment.
My hypothesis for this experiment was not what I expected it to be. Instead of having each section grow in size due to the solution was incorrect. I only had my 1% with solution grow. This is the lowest concentration level I had and my lowest number of brine shrimp in the section without concentration as well. The other sections with my 5% and my 10% concentration ended up with no hatched eggs at all.
Environmental Science and Sustainability (SCI201 -1504A -07) Instructor: Trena Woolridge Unit 4- Discussion Board Amanda Kranning October 27, 2015 Eutrophication is a syndrome of ecosystem responses to human activities that fertilize water bodies with nitrogen (N) and phosphorus (P), often leading to changes in animal and plant populations and degradation of water and habitat quality.(Cloern, Krantz, & Hogan, 2013) Eutrophication forms when an abundance of nitrogen and phosphorus increases growth within an environment.
The starting population of the experiment contained 100 organisms that had 10 different Dottus Variengatus phenotypes. A multicolored-city board was used to simulate the environment where these organisms lived. To perform the experiment, groups of three were formed. The first member had to act as a new predator of the population, the second member was assigned to randomly disperse the colored dots on the board, help keep count of the consumed dots, and collect materials at the end of the experiment. The third member had to collect the prey from the predator, and help keep count until 25 dots were collected.
Natural Selection is the concept that organisms better adapted to their environment tend to survive and produce more offspring. This leads to the creation of populations and diversity of life within them. In the Skittlefish Lab, many separate occurrences can be observed which detail and explain how Natural Selection works on a population over a period of time. Certain adaptations in a species in its entirety may display how individuals impact the whole population as they pass their traits onto their offspring, which do the same. This lab required students to observe the individual “Skittlefish” and “Sea M&Ms” in different environments as they camouflaged and hid from predators.
This one explanation full illustrates the importance of a balanced ecosystem and how the introduction of a predator can make sweeping changes in the
Our model does show mainly the trophic interactions; however, the model could also be used to infer other types of competition interactions. For example, space is a resource and with this model we are able to estimate the relative abundances for each of our species and if we compare the amount of physical space that is needed to support these populations with the actual size of the Columbia and Snake River Basin’s we can get a rough idea of how much space is needed to support these organisms. Evaluating this interaction would be between all species competing for physical space to
The purpose of this lab was to test the effect of pollution on algae growth. Through a series of experiments that lasted a month, four of the six hypotheses were proven to be correct or partially correct. The first hypothesis stated that if 0.5 mL of salt was added to algae, then the algae would grow slower than the positive control. This was proven correct, as shown by the difference of the data from the positive control and the container with 0.5 mL of salt in it.
Predators then eat the animals who eat the plants and each
The Florida Everglades is home to lots of animals, predators and plants it's home to the people that live in Florida and also to the people that care about it the everglades is a wonderful place I actually want to go there my self and see the animals and plants it's actually the habit to those animals and plants The Florida Everglades has many values it's home to the wildlife animals though it can get crazy sometimes when the animals starting to get hungry. Python and baby anaconda's are taking over our wildlife animals by killing and eating them the population of our wildlife animals have went down the Everglades according to the text it states. '' Reports from just over a year ago say that thousands of pythons have been making their homes
Introduction Predation is a biological interaction between two organisms of different species in a community in which one acts as a predator and captures and feeds on the other, the prey. Predator-prey relationships keep animal populations in balance. When prey populations increase more food is available for predators, and they increase in number as well. An increase in predators triggers a decrease in prey populations. As prey populations decrease predator populations soon follow as their food supply diminishes.
Although the exponential growth model is the basis of this model, population ecologists have developed this to model the reality of limited resources. This model illustrates how a population may increase exponentially until it reaches the carrying capacity (the number of individuals of a particular species than an environment can support) of its environment. The logistic growth model looks like this when it is illustrated
The Biotope Aquarium Explained In a biotope aquarium, the aquarist attempt to simulate a natural habitat, assembling fish species, plants, water chemistry and decorations found in that specific ecosystem. A “true” biotope should be a mirror of a natural habitat. There are many good reasons for setting up an aquarium that simulates a natural habitat. Those of us who have done everything, bred everything and kept most fish might simply want a new challenge.