After precisely conducting the experiment and tabulating the results, data for Paraquat toxicity upon P. vulgaris plants can be interpreted over several different parameters. The parameters by which Paraquat toxicity was examined within this experiment involve visual observations, x-ray diffraction, chlorophyll concentrations, protein concentrations, and lastly malondialdehyde (MDA) concentrations on a per mg of protein basis. As stated before Paraquat is very widely used herbicide known to produce superoxide anions leading to chloroplast membrane damage and ultimately a variety of adverse effects upon the host organism, in this case P. vulgaris (Chia et al., 1982).
Citrobacter Freundii is a species of bacteria that can be potentially harmful to humans. It is known to cause meningitis by protruding into the brain and replicating itself (1). The Citrobacter species has also been found as a cause of some urinary tract infections, diarrhea, and even gastrointestinal diseases and symptoms (3). C. Freundii can be located in a wide variety of soils and water (3). Lastly, it is also the cause of many nosocomial infections due to its presence in water (1).
A plant's growth ability is dependent on its ability to acquire the resources it needs to survive. Competition such as interspecific and intraspecific, limiting resources, and population density affect the fitness level of a plant. This experiment was conducted in order to test the capability of collards and radishes to grow in manipulated densities under interspecific and intraspecific competition. I hypothesized that both collard and radish plants will grow more efficiently in single species pots under low-density conditions. I also hypothesized that in the mixed species plots the radishes will be more fit to survive and grow better than the collard plants in both the high and low-density pots. Both high and low density and single and mixed species plots were planted and results were observed. There was a significant
In this lab, the organism that we have been working with is the bacterium, Serratia marcescens. S. marcescens is a member of the Enterobacteriaceae family, and tends to grow in damp environments. S. marcescens is an ideal bacterium to work with in the lab because it reproduces quicker than other bacterium. This bacterium produces a special pigment called prodigiosin, which is red in color. The prodigiosin pigment is intensified when S. marcescens is grown at higher densities. During our experiment, temperature, pH, salinity concentration and oxygen requirements were tested on S. marcescens to measure their optimal growth and prodigiosin production.
If feeding efficiency and reproduction have a direct correlation, and a population started with equal proportions of individuals with each of three feeding types, metal spoon, metal knife, and plastic fork, the frequency of the population with metal spoons as their feeding structure will increase in the next generation. While the frequency of metal knifes and plastic forks will decrease. Furthermore, since the organisms with the metal spoon feeding structure have a higher fitness level, this population will evolve by natural selection to a point where the metal spoon phenotype will be in abundant. While the organisms with metal knifes and plastic forks phenotypes will decrease in frequency due to the lack of reproduction. Eventually, if this population persist overtime, most of the organisms, if not all, will have the metal spoon phenotype, while very few, if not any, will have the metal knife or the plastic fork phenotype.
Regarding temperature changes, the null hypothesis is that their heart rate will remain constant regardless of increasing or decreasing the external temperature of the Daphnia. The alternative hypothesis is that the heart rate will increase with more heat and will decrease with a decrease a decrease in temperature, meaning that heart rate and temperature are directly related. In regards to the chemicals acetylcholine and epinephrine, the null hypothesis is that both chemicals will have no effect on the heart rate of the Daphnia. In contrast, the alternative hypothesis is that their heart rate will increase with exposure to epinephrine and decrease with exposure to
Prior the conduction of this experiment, Sordaria of different ascus types (WT and T) were exposed to significant levels of radiation. There were three experimental groups for this experiment and crosses accordingly. Crosses were set up in containers by placing different Sordaria groups in alternating fourths of the mating agar. The Sordaria naturally grew outwards to the different adjacent Sordaria groups and inter-mated through meiosis. This provided a variety of different crosses throughout each experimental group. The squashes were prepared by obtaining a clear slide and placing a small amount of water in order to trap and spread out the perithecia. Once the individual perithecia were separated, they were busted by applying slight pressure with an eraser head, but done carefully enough not to pop the individual sacs. Frequencies were calculated by counting the number of
For this lab 6 male Acheta domesticus were isolated in plastic containers, each was placed in a container that was 5 cm height and had 5.5 cm radius. Each of these containers was punctured with 10-15 minuscule holes for breathing on the lid and 5-8 holes on the sides. Inside of each container a damp paper towel was placed on the bottom and 2 pieces of food were placed on the paper towel. The Acheta domesticus were kept isolated in their personal containers for 7 days. At the end of these 7 days we split the 6 A. domesticus into 3 groups of 2. One of the two was marked with a paint pen, this marked male was the “intruder”. The remaining food was removed from the containers. The “intruder” is then placed into the container that holds the other
9. In the research done on the microbial community in the Rhizosphere using two methods, which are the Cultivation-dependent method and Cultivation-independent method. The research and studies done had good results, moreover, the physiological profiling was done in 5 days by the use of several carbon sources. The maximal growth was observed for the 30 degrees celsius- incubated plate by day 3, whereas comparable values were recorded for the room to the temperature-incubated plate by day 5.
Background- This lab is being done to demonstrate the effects of stimulants on the circulatory system of blackworms. In this lab, the stimulant we have chosen to use is Nicotine. A stimulant is an agent that causes increased activity, especially in the nervous or cardiovascular systems. In this lab, we will put blackworms into the Nicotine to look at the differences in pulse rates when compared to a control. The proper name for blackworms is Lumbriculus Variegatus, they are freshwater worms most commonly found in North America and Europe. The blood in blackworms circulates from the dorsal blood vessel toward the head through a series of
Population Growth: Density dependent factors Abstract Sets of experiments were used to assess the growth rate of the Lemna minor, a duckweed population. The growth of Lemna minor was observed and followed by counting and recording the number of thalli on a weekly basis. These experiments were constructed lab models which varied the size of the starting thalli population, and varied the nutrient concentration the thali were placed in. In the first experimental model two plastic cups were prepared with pond water, then two healthy lemna minor plants were placed in the first cup while fifteen healthy lemna minor plants were placed in the second cup. The second experimental model consisted of four nutrient concentrations, a control model of no nutrients, a low nutrient model, a medium nutrient model and a high nutrient model. At high density populations, we observed a nonlinear decreasing growth rate with increasing lemna minor density. At very low densities, as expected, we observed an inverse density dependence. Duckweed reproduces by budding, causing a larger density to reproduce a greater amount of biomass. This would indicate that Duckweed likes overcrowding, and this may be a possible clue to the limiting factor in the growth of Duckweed. Introduction Lemna minor, commonly known as duckweed, is efficient and fast growing, making it an ideal experimental organism. It is known as a small aquatic monocotyledon which can be found floating in ponds, lakes or streams (Harper,
Streptococcus pneumoniae is a bacterium pathogen that needs a host in order to survive, which are usually humans (Donkor, 2013). The bacteria is the cause of diseases such as pneumonia, meningitis, sepsis, and corneal ulcers. Some of the diseases S. pneumoniae causes are extremely harmful to humans and can even cause death in some cases (Mathos, Ferri, Figueiredo, Zangirolami, & Gonçalves, 2015). Humans, who already have a S. pneumoniae disease or have the bacteria simply in the upper part of the pharynx, transfers the bacteria through air particles, known as aerosols (Donkor, 2013; Lawrence, S. L. et al., 2015). In well populated areas or places, like schools, colleges, workplaces, S. pneumoniae is able to infect many humans
This lab about the growth of penicillum. Whether it grows faster on cold objects or warm objects. If it even grows at all. When in certain temperatures and places the bacteria will grow and spread. My hypothesis is when the I leave the orange, lemon, and cotton ball in a dark warm space the bacteria will grow at a faster rate than in the cold. Penicillium has over 200 species. It's usually found in dirt, rotting fruit, and dead plants. Some people refer to it as black mold.
The purpose of the paramecium experiment was to observe competition or allelopathy between two different species of paramecium in the laboratory. Allelopathy is a way organisms inhibit or affect other organisms when developing in nature. This insures the survival of one organism against another organism. For instance in plants, some can release a chemical that enters the environment and inhibits the growth and development of surrounding plants. Another example in nature is plants developing defenses to prevent herbivores from eating them. This kind of competition happens in nature when the need for resources is limited and survival is necessary. Competition is displayed throughout nature all the time. A man named Georgy Gause previously conducted this experiment between P. aurelia and P. caudatum. He determined that different factors influence how the two species compete and coexist. Ever since then not many scientist have attempted to experiment on paramecium. Only until recently have more experiments been attempted. The issue with the experiment was that it was conducted in 1935 and nowadays there are more advance ways to conduct and interpret the experiment and results.