Daphnia Sp Biology Lab Report Sample

Table 2: Mann-Whitney U statistical testing for the difference in average heart rate of Daphnia before and after the addition of aged water:

Seeing as Daphnia are living organisms, it provided equal opportunity to act on these criteria. There were many actions I performed in order to this. I made sure I did not leave the Daphnia underneath the light for too long as it would kill them. I also reintroduced them into their existing environment. This not only took into consideration the wellbeing of the Daphnia but also their environment as well. Also I did not expose to too much caffeine as I did not want their hearts to stop nor did I want to drown them. Also while transporting them to various environments I took a good amount of care and used a pipette to contain them within their own natural

We performed an experiment on crayfish focusing on their metabolic rates, via oxygen consumption, at two acclimated temperatures. Crayfish were either acclimated to a warm temperature (20 to 25C) or to a

The Artemia franciscana can survive in extreme conditions of salinity, water depth, and temperature (Biology 108 laboratory manual, 2010), but do A. franciscana prefer these conditions or do they simply cope with their surroundings? This experiment explored the extent of the A. franciscanas preference towards three major stimuli: light, temperature, and acidity. A. franciscana are able to endure extreme temperature ranges from 6 ̊ C to 40 ̊ C, however since their optimal temperature for breeding is about room temperature it can be inferred that the A. franciscana will prefer this over other temperatures (Al Dhaheri and Drew, 2003). This is much the same in regards to acidity as Artemia franciscana, in general thrive in

The major storage polysaccharide in plants is starch. These molecules would be found in abundance in the stroma in the plant tubers where it is found as granules. Glucose is stored mainly in the form of starch granules, in plastids like chloroplasts and amyloplasts. Plant starch starts out as glucose, but glucose is very hard for plants to store, so it is converted to starch through polymerization. Amyoplasts turn the glucose into starch and move it to the stroma, and in tubers the stroma is a place to store the food (starch), and when plants need the energy in the starch, it converts the starch back into glucose.

The purpose of this experiment was to test the affect of caffeine on the heart rate of Daphnia by observing their behavior and heart rate under a microscope when exposed to different concentrations of caffeine. Caffeine is a stimulant drug used in many energy drinks and causes large amounts of stimulatory neurotransmitters to be released. Therefore, as caffeine is a stimulant drug it was hypothesized that the Daphnia heart rate would increase immensely. Daphnia is a group of microscopic, planktonic crustaceans that are arthropods that measure 1-5 millimeters in length. Daphnia live in multiple aquatic environments such as freshwater lakes, ponds and rivers. “The development of genomic infrastructure coupled with a wide range of phenotypic diversity make Daphnia a versatile model

Daphnia, Branchiopoda, are categorized under the phylum Arthropoda and subphylum Crustacea. Daphnia are planktonic and are characterized by flattened leaf-like legs used to produce a water current for the filtering apparatus (Ebert et al. 2005). Daphnia are suspension feeders, which is one reason why they are used in this experiment. The purpose of this experiment is to see how Nyquil® and ethanol affect Daphnia heart rate. Nyquil® is a pharmaceutical drug that is used to treat common cold, aches, or pains, and the main ingredient is acetaminophen. Acetaminophen is a pain reliever that, like other antibiotics, inhibits protein synthesis, and has proven to immobilize Daphnia in even low concentrations (Daughton et al. 1999). There are many reasons why we use Daphnia in science; one reason is that the Daphnia hear rate variation test can be used in evaluating the effect of xenobiotics and in selecting agents for the pharmacological correction of this functional parameter (Dolgo-Saburov et al. 2008). We predict that Nyquil® decrease the heart rate while ethanol will increase it.

The daphnia relies on an osmotic gradient, as they are able to take in ions with their chloride absorbing glands, which help the organism to secrete and absorb ions by supporting the inadequate effectiveness of excretory organs to complete homeostasis under dehydration and extreme conditions. Therefore under the influence of increasing salinity, daphnia will face dehydration from high levels of concentration and will lead to the death of the species (Komnick, 1986).

The experiment took place in a laboratory setting, and the first step was obtaining sixty individual Daphnia magna (that were neither adults nor tiny offspring) from a large tank in the lab. These individuals were equally divided into three groups; low density, medium density, and high density. The twenty Daphnia assigned to the low density group were split into four groups of five and pipetted into one of four tubes filled with 10mL of Chlamydomonas algae. The twenty Daphnia assigned to the medium density group were split into two groups of ten and placed into one of two tubes also filled up to 10mL with Chlamydomonas. The final twenty Daphnia were all placed into a single tube filled with 10mL of the algae. In order to avoid suffocation-related

Aaron, I feel like with depression the diathesis all mix together. You're right, little is known about the biological diathesis, but I believe that everything (biological, social, and psychological) plays a little part. Unless there is one commonality between all depression sufferers, I believe that it is a mix. When you said that someone not having someone else to talk to can contribute to depression, I completely agreed. With depression (and many other mental disorders), the causes are just as diverse as the people that suffer from it. Anything that seems "small" or "irrelevant" might be a huge part of the cause, no matter how "small" that issue is. Thanks for sharing!

The real hypothesis states that the chemicals contained in the milkweed provoke a change impacting the heart of the Daphnia causing an increase of its heart rate. On the other hand, the null hypothesis asserts that the toxins of the milkweed would lessen the heart rate of the little invertebrate.

In our study, we had two separate experiments to test whether the water temperature impacts the locomotive activity of Hemigrapsus oregonensis. We modified our second trial by using water of higher temperature variations (more severe environment), removing the sand from the bottom of the tub, and introducing 5 seconds acclimation period before we started the three-minute-timer. With modifications, we recorded two absolutely opposite results from two trials: in the first trial, the data illustrated that the crabs moved a longer distance as temperature increased, but in trial two, crabs appeared to be less active and moved less as we raised the temperature. A study by Gillooly (2001) proposed that higher temperature, which is the result of higher kinetic energy of cellular components, is linked to resting metabolic rate being higher. Species with higher metabolism synthesize more ATP in their bodies, and consume more oxygen to move around. Furthermore, scientist Burggren (1997) claimed that almost all poikilothermic animals follow a similar pattern: a decrease in body temperature will result in decreasing cardiac activities. Since body temperature changes along surrounding temperature, a change in water temperature in our case will also indirectly affect the cardiac activity of H. oregonensis. The main function of cardiovascular system is oxygen and nutrient transportation. The central cardiovascular system may slow down because of a decline in temperature increase the

The study was conducted to find the effect of temperature, humidity, and light on three different animals (Warburg, 1964). One of the animals, Armadillidium vulgare, is also similar to Porcellio scaber as they are both isopods that exhibit similar behaviours, especially in terms of their water-permeable exoskeletons. In the study, the animals were place on a temperature gradient with different temperature ranges (10oC to 20oC, 13oC to 27oC, 21oC to 35oC, and 28oC to 45oC). The study was done with a simultaneous treatment experiment. The position of the animal was recorded after every 60 seconds and the time the animal spent in each temperature zone was also recorded. The result of the study was that the organisms preferred to stay longer in a cooler region which does not support our results of duration is unaffected by temperature. Porcellio scaber is susceptible to water loss due do the environment so their natural behaviour would be to stay in areas where water loss is

Chlorophyll a averaged 0.71µg/cm2 across all sites and sample periods and ranged from 0.03 to 3.42µg/cm2. Before the disturbance, Chl a at the SFD sites was lower at Dry Hollow (mean ±1SE; 0.21 ± 0.08 µg/cm2) than at Sis Hollow (1.11 ± 0.37 µg/cm2). Chl a values were similar between the IFD sites [Point Remove and High Cedar (0.51 ± 0.26 µg/cm2 and 0.69 ± 0.37 respectively)]. They were higher at the LFD site, Powerline, than at Low Cedar (1.84 ± 0.55 and 1.04 ± 0.33 µg/cm2 respectively). There were no differences between control and impacted sites prior to the disturbance (Table 4). There were no statistically significant 2-way rmANOVA interaction terms between the BA and CI factors for any of the flow duration parings

Water velocity plays an extremly important role in fish bioenergetics. It effects components that are detrimental to fish as