Circadian Rhythms Lab Report

The first variable tested was phototaxis, the movement toward or away from light. To do this, we used an empty petri dish and filled the bottom of it with filter paper. We then added five sowbugs to the petri dish and placed a lid on top. After leaving the sowbugs alone for three minutes to get acclimated to their new environment, we placed a lamp directly over the petri dish. Then we laid a piece of cardboard over the petri dish to cover exactly half of it, leaving the other half exposed to the lamp. We want the cardboard to cover close to half of it as possible to make the data as accurate as possible. The lamp was then turned on and the number of sowbugs in the light and dark locations were recorded every minute for the next twelve minutes. As shown in Table 1, we determined that sowbugs are effected negatively by phototaxis.

All mouse would be train to go through a water maze after their blood treatment. Scientists would take notes of the errors and time for the mice to get out the maze. In the first tried, both mice had about the same number of errors before exiting the water maze. However, on the second test, the mouse treated with young blood would have less error and could escape the water maze faster than the mouse treated with old blood. This experiment demonstrated how the mouse treated with young blood would learn its own mistake faster and have good sense of

Ever since the late 1960’s and the early 1970’s, animal research has been under extreme fire for what they do. This is mainly due to the many changing perspectives on the relationship between humans and the other aspects of the world that are surrounding them. There are many main reasons for this change, but the main reason is the different ideas that surrounded the use and exploration of animals in laboratories is what is being brought into question.

This study will be comprise two experiments. The animal trials will be conducted at the Experiment Research Station and the laboratory work in the facilities of the Institute of Animal Science, University of Hohenheim. Field studies will not be included.

During the first experiment the Sprague Dawley rat (male) was obtained at weaning. These rats are commonly used in medical research due to the advantage of their calmness and ease of handling. During the first experiment the rats were addressed to housing in either groups of 4 (GR) or alone (IR). This was constructed of Plexiglas cages with different measurements

One of the most important findings in schizophrenia is an abnormal hippocampal structure (Weiss et al., 2005). Evidence from post-mortem examination and patient’s brain imaging have shown the decreased volume and the presence of an abnormality in the shape of the hippocampus (Bogerts et al., 1990; Nelson et al., 1998; Wright et al., 2000; Shenton et al., 2002). These neuroimaging findings have also been observed in individuals in the first episode or prodromal phase of schizophrenia (Shenton & Gerig et al., 2002). Structural imaging studies have suggested that reduced hippocampal volume is extended through the frontal to posterior regions, and it is not restricted to a particular region of the hippocampus (Weiss & DeWitt et al., 2005). Studies have shown differences in morphology (size, organization, shape) of hippocampal neurons (Benes et al., 1991; Arnold et al., 1995; Zaidel et al., 1997; Shenton & Gerig et al., 2002).

As a scientist opens the rusty cage door, the fuzzy hamster bolts to the very edge so that the scientist would have trouble getting the mouse out. The hamster squeals, cries, and shivers, as the huge hand wraps around its body pulling the hamster out of the cage. As soon as the hand releases the hamster, the scientist injects numerous amounts of chemicals into it. The chemicals are so toxic that the mouse lost its life instantly. Even though many researchers chose to use animal testing, that is one of the many ways of research. Animal testing should no longer be needed since there are better, alternative ways to research without harming live animals.

Perelman School of Medicine at the University of Pennsylvania was trying to find out how the amount of sleep affects your body mentally. This is important so we know how to take care of ourselves and stay healthy. To test this experiment, the Perelman School of Medicine got a group of 40 adults and put them into two different experimental groups. They were placed in either a group where they stayed up for 28 hours consecutively or in a group where they received a full 8 hours of sleep. Afterwards, all participants took a computer based test. The students studied how the participants reacted to happy, neutral, or sad faces through accuracy and response time. Overall, the studies showed that the participants who stay up for 28 consecutive hours

Albino Wister rats of either sex weighing between 150 to 200gms were divided into Six groups of 6 animals each.

Stress is one of the most major factors responsible for depressive disorders [1,2]. The chronic mild stress (CMS) model, a widely used rodent model of depression, consists of repeated exposure to various of unpredictable and mild stressors and it. And it has been shown a decrease in reward sensitivity in various behavioural paradigms [3] induces changes in hypothalamic-pituitary-adrenal (HPA) axis [4,5] but also of other biological and behavioural markers of human depression, including architectural sleep abnormalities[6,7] disturbances in circadian rhythms related to locomotor activity[8]using of variety of drug treatments during the application of stress can be reversed these disturbances

Another major pitfall of this experiment may be the small sample size of mice that is used. Due to the inconsistency

What was the sample size for this experiment? The article does not tell you the number of mice that were researched in the experiment, and because of this, we don’t know how reliable the data is. The sample size, for all we know, could be very low (say, 10 or 100 mice), and if that were the case, it wouldn’t be a very good representation for a much larger population of people. We need to know how large the sample size is in order to come to a better conclusion over how reliable the data is.

The Clock is Running – Let’s See How Fast You Can Go and Change Directions at the Same Time!

Animal models in experimentation serve in an imperative role. Currently, substances intended for human use (drugs or devices) must be tested in an animal model first to determine if they must be adjusted, denied or approved. Research conducted on diseased animals provide insight to progression of similar diseases in humans, improve knowledge of biological responses to various substances and devices. They also result in the production of various products such as food additives, agrochemicals, vaccines, implants and pharmaceuticals. “It has been estimated that more than 1,200,000 species of animals have been described, but 97% of the animals used for biomedical purpose belong to only 10 of them. They are rat, mouse, rabbit, chicken, dog, guinea pig, pig, hamster, monkey, and cat”(Pal). Roughly, 95% of studies are conducted in mice (Dey). A different species is used only when it is a more closely matching system to the equivalent in humans. Many things must be considered when choosing a model for research; availability, anatomic characteristics, stage of life,

This paper explores four articles relating to experimenting on laboratory animals in order to answer two questions: should we continue to use of animals for testing and what are the alternatives of animal testing.