You are here

vvikhrev's blog

Draft #5, week 3, Background info on Ludisia

Submitted by vvikhrev on Fri, 02/09/2018 - 12:14

On the methods project -
This morning I went to the greenhouses that we have here at the university. The greenhouse I entered was called the “tropical garden” I believe. This is something that I will definitely have to double check. The species name of the flower I chose is: Haemaria discolor. If belongs to the genus: Ludisia and to the family or: Orchidaceae. It’s common name is the Jewel Orchid. It appeared to be in its optimal environment because it was in full bloom, looked very “plump” and healthy. It was definetly a beautiful flower and caught my eye because it closely resembles the flowers that grew near my childhood home (their species name is: Convallaria majalis, but most people know them as the Lily of the Valley). Another intriguing characteristic of these flowers were their leaves. They are about 3 inches long and are a deep green color with some hues of maroon. They also have white lines that run parallel to each other from the base of the leaf towards the peak. Their stem is long and thin and the flowers that have already budded are white with some type of yellow center.

Week 3, Perfect Paragraph

Submitted by vvikhrev on Fri, 02/09/2018 - 11:16

During the methods part of Rosenzweig's research, several experimental factors had to be considered. In order to avoid bias, the examiners were not told which rat’s brain belonged to which of the three environments. After the treatment period, the brains were measured, weighed and analyzed to determine cell growth and levels of neurotransmitter activity. A neurotransmitter called acetylcholinesterase was the focus of the chemical examination. This neurotransmitter is responsible for faster and more efficient transmission of neural impulses. The cerebral cortex of the brain is responsible for experiences, movement, learning and sensory input. It was found to be heavier and thicker in rats raised in the enriched environment compared to the rats raised in the impoverished environment. The rats that inhabited the enriched environment also had increased acetylcholinesterase activity, had larger neurons and a higher RNA to DNA ratio. No differences were found between the number of neurons. Rosenzweig assumed that these differences implied higher levels of chemical activity had taken place. These results were seen again when they performed the same experiment several more times. The cortex increased in weight in response to the type of experience in each environment type, but the sub-cortex (the rest of the brain) changed very little. This measurement of the cortex to the sub-cortex was the most accurate measurement because overall brain weight varies with the overall weight of each animal (there is no correlation). They also found that enriched synapses were much larger in the rats that came from the enriched environment. These experimental results all supported the hypothesis which stated that animals raised in highly stimulating environments would demonstrate differences in brain growth and chemistry when compared to animals reared in plain/dull circumstances.

Draft #4, week 3, Rosenzweig's research cont..

Submitted by vvikhrev on Fri, 02/09/2018 - 11:06

Continuing my notes from draft #3 of this week –
Discussion: There were many critics of his research. One of the biggest reasons as to why there was so much criticism was due to the fact that such type of experiment and also his theory have never been performed nor wondered about. What was the role of nature in a humans development? Is it correct to assume that all the results of this experiment applied to humans as well? These were the big questions. The researchers answered honestly saying that, no, we cannot assume that this applies to humans as well but we can assume that these results can be used for further research (as technology develops) which is the most important aspect of our results. This was a very broad criticism but there were more specific questions posed. Critics said that the differences in the brains of enriched v. impoverished environments could be due to stress and handling, since the rats from the enriched environment were handled 2 times a day and the impoverished rats weren’t handled at all. Rosenzweig tested this by setting up an experiment where he put rats in the same type of environment (but two separate cages) and handled one set of rats 2 times a day and the other set zero times a day and he found that there were no differences in brain size, weight and cortex to sub-cortex ratios. Even in later studies of the main experiment, they handled all the rats the same and they found no differences. Some critics also said that stress could have caused the differences they saw and not the enriched environment experience. But other evidence from separate research saw no differences either.

Draft #3, week 3, Rosenzweig's research

Submitted by vvikhrev on Fri, 02/09/2018 - 10:56

Rosenzweig’s research
Theory: The experiences that a human faces during early development has an effect on the development of the brain
Hypothesis: Animals raised in an enriched (highly stimulating) environment will demonstrate differences in brain growth and chemistry when compared to animals raised in a plain/dull environment
Why use rats? First of all, using humans would be ethically wrong for this experiment. Using rats (versus using another animal) is a better option for many reasons. Their brains are smooth therefore it can be measured and examined more easily after they are killed, they are small and inexpensive and last but not least, large litters allow researchers to also study the role of genetics which is especially useful in nature vs. nuture experiments such as this one.
Methods:
- 12 sets of rats, 3 male rats from the same litter, each of the 3 “brothers” placed in the 3 separate environments
- 3 different environments: the control = with the rest of their colony or in an enriched environment or in an impoverished environment
- treatment period was 4-10 weeks
To avoid bias, the examiners were not told which rat’s brain belonged to which of the 3 environments. After the treatment period, the brains were then measured, weighed and analyzed to determine cell growth and levels of neurotransmitter activity. A neurotransmitter called Acetylcholinesterase was the focus of the chemical aspect of the examination. This neurotransmitter is responsible for faster and more efficient transmission of neural impulses
Results: The cerebral cortex is the part of the brain that responds to experiences, responsible for movement, learning and sensory input, therefore it was the center of the study. It was found to be more heavy and thicker in the enriched environment compared to the other two environments. The brains that inhabited the enriched environment also had increased acetylcholinesterase activity, there were larger neurons (however, no differences between the number of neurons) and the RNA:DNA ratio was higher in the rats that came from the enriched environment. They assumed that this implies higher level of chemical activity had taken place. These results were repeated when they performed the same experiment several more times. The cortex increased in weight in response to experience, but the sub-cortex (the rest of the brain) changed very little. The measurement of the cortex compared to the sub-cortex was the most accurate measurement of all the other measurements because overall brain weight varies with the overall weight of each animal. They also found that enriched synapses were much larger in the rats that came from the enriched environment.

Draft #2, week 3, The One Right Way to Talk Science

Submitted by vvikhrev on Tue, 02/06/2018 - 21:37

The Right Way to Talk Science summary –
I think that every category of academic language has its own style and to write in any kind of language takes practice. Each type of style of writing has its own “recommended” grammer, choice of words, idioms, metaphors and most importantly, stylistic device. However, there are probably more boundaries in the language of science than in any other language. The most important thing to remember is to keep your scientific writing concise, simple, and clear for the audience. You do not want to create a circle for the reader. Your purpose is to convey your knowledge to them and make them understand the purpose, significance, and what your experiment means for the future overall. What are the norms of scientific study? One way to answer this question is to study and engage in a science class. It is easy to notice that personification in scientific language is NOT scientific and is unacceptable, however in a classroom, when introducing a new topic, this kind of approach may be more helpful for the student’s understanding. One norm is to be as verbally explicit and universal as possible and another norm is to avoid colloquial forms of language and use even in speech (pg 133). Avoid sensationalism, metaphoric and figurative and metaphoric language, personalities and personification, and references to fiction/fantasy (pg 133).

Draft #1, week 3, WIB textbook Ch. 6

Submitted by vvikhrev on Tue, 02/06/2018 - 12:27

- before writing your first draft of your lab report, it is important to understand the experiment, take good notes and make good observations
- the goal of a lab report is the same regardless of structure variations: “document your findings and communicate their significance” (pg 89)
- an ideal lab report is in IMRAD format: Title page, Abstract, Intro, Materials and Methods, Results, Discussion, etc
- this format is supposed to represent a textual version of the scientific method: developing a hypothesis, testing it and deciding whether your findings support the hypothesis
- presenting your ideas, results, methods and background information is one thing, but it is more important to convey your understanding of the results, write a thorough discussion and show your knowledge of the why and how
- it may seem that the title is not as important as the rest of the sections however, it is the first thing that a reader sees and judges on whether or not he/she will read the article, the title needs to be 3 things: clear, succinct and complete
ex: avoid phrases such as “a study of..” and only use well-known abbreviations such as DNA or RNA, avoid general and
vague titles
ex: to make sure the title is complete, compare it to your hypothesis
- not all lab reports have title pages, so make sure to check what the requriements are for that particular report
- why is writing an Abstract one of the most important skills in science? because all of your work will be judged based on what is written in the abstract
- guidelines for writing abstract: summarize the contents of the report in one paragraph, written so that it can stand alone, include only the most important details of the paper, use as few words as possible (lab report abstract are about 50-150 words long)
- there are five things that need to be included in the Abstract paragraph: question/purpose, experimental approach, results, conclusion/implication, optional: scientific background and significance
- your abstract can end with a sentence stating an implication, etc, but is should not end with a general descriptive statement that merely hints at your results
- Introductions serve a purpose to interest your reader, to provide sufficient background info so that they can understand why youy study was performed and what specific research question/hypothesis you addressedd
ex: for lab reports, they are short, state the hypothesis, maybe the approach and contain some background info
ex: for a journal article/research paper, the introduction is longer, contain additional details and background info as
well as a very specific unknown to explain the overall purpose

In-class assignment week 2

Submitted by vvikhrev on Fri, 02/02/2018 - 15:23

In order to remain productive and accomplish my daily tasks, I had to make a To-Do list that contained all the things that needed to be done after my last class. The most important task was paying my insurance bill because the policy was about to expire, the office is 45 minutes away and it closes at an inconvenient time of 4:30 p.m. After getting that out of the way, I headed home. When I got home I put in a load of laundry and started to make a chicken and sweet potato dinner. After I ate, I cleaned up in the kitchen, washed the floors, and sat down to do my homework. At 8:00 p.m. my sister needed to be picked from work. Once that was done, I came home and put in the last load of laundry and folded the dry laundry and sat down to finish my homework. Before taking a shower, I organized my desk. After my shower, I brushed my teeth, prepared everything I needed for tomorrow and got into bed. I fell asleep right away.

Draft #6, week 2, Sensory Neurobiology notes

Submitted by vvikhrev on Fri, 02/02/2018 - 09:32

the sensory systems collect signals in the environment and convey them to the CNS
sound: change of air pressure
- action potential can upkeep an amplitude for a long distance because it can regenerate itself due to the Na+ channels
- amplitudes don’t differ in the same neuron, but can differ across neurons
- action potential doesn’t carry info, it is the timing (the signal is digital)
- change in the environment provide signals (light, chemical, mechanical)
Mechanical = Touch and Hearing (hearing is the movement of physical objects, no physical contact)
Chemical = Olfaction and Taste
- conversion happens in 3 steps
1. electrical signals of the environment converted into receptor potential
2. needs to be sensed by a receptor, becomes converted into electrical signal in the receptor = membrane potential = receptor potential (if it happens in the receptor)
- receptor potential is incremental and is reflecting the signal in the outside
3. receptor potential converted to action potential along the afferent fiber (action potential is digital = can propagate long distance w/out changing amplitude
What is in common?
- parallel processing in multiple pathways, work in parallel, in any given time, all of them are telling something to the brain, true for all sensory systems
- two steps processing
- the difference is the receptor, convert external signals into incremental change
(axon terminal = receptor potential at a receptor, variation among type of sensory system)

Week 2, Perfect Paragraph

Submitted by vvikhrev on Thu, 02/01/2018 - 21:54

This week we had to read Chapter 3 and 7 from the “Writing in the Biological Sciences” text. In my opinion, the most important factor to remember when writing is to always write with the reader in mind. After you have already formulated your hypothesis, performed all the necessary experiments and research, it is time to focus on who is going to be reading your writing. Ask yourself: “what is the most important piece of information you would like to convey to your audience?” Remember to write clearly. For instance, the first paragraph of this chapter mentions that we need to take into account how the reader is going to interpret our writing. If we were trying to appeal to a feeling or evoke some kind of emotional response from our reader then we would lean towards using fancy, and flowy language and phrases. However, when trying to communicate scientifically, that kind of writing is unecessary and instead it makes more sense to use precise, clear language that is easy to understand and is correctly worded. It is important to establish importance in a sentence as well. Depending on where a certain phrase is placed and what punctuation is used, it can be viewed as something negative or as something positive. Old information is placed at the beginning of a paragraph and new information that needs more emphasis, is placed at the end of a sentence. Last, but not least, we need to remember to use past tense for observations, unpublished results, and specific interpretations and to use present tense for general rules, accepted facts and established knowledge.

Draft #5, week 2, Structure on Scientific Lit

Submitted by vvikhrev on Thu, 02/01/2018 - 21:24

The abstract sections of each of the articles were about a paragraph long. The textbook writes that the overall structure of the abstract should conform to the following outline: “content: question/purpose, experimental approach, results, interpretation/answer, significance” (pg 115). Considering that both of the abstracts are only a paragraph long compared to the other sections (the introductions are several paragraphs long), it seems kind of impossible to accomplish this. Yet, the writers of both articles were able to provide a thorough paragraph with all essential parts included. The article from the Ecology Letters journal contains the topic sentence as the first sentence and there is a logical flow of ideas. It is organized by giving the background sentence first (the known), the two sides of argument. Then, what the researchers are trying to accomplish (the unknown), their approach, the conclusion they came to and last but not least, their interpretation of their results. The other article’s abstract is somewhat different since it is not necessarily an experiment but rather just an interpretation of several other experiments in order to answer their hypothesis. There is no topic sentence, but the first 4 sentences provide the reader with a background that gives the purpose and of their research so, they could be seen as topic sentences of significancy. There is no experimental approach because this is not an experiment but they do state that they are going to approach their hypothesis by reviewing (comparing and contrasting possibly) the invasion histories of several species. There is a logical flow of ideas and overall, the abstract is well organized.

Pages

Subscribe to RSS - vvikhrev's blog