Drafts

Summary of Thomson, “A Defense of Abortion”

In this article, Thomson defends abortion using several metaphors. In section 5 until the end, Thomson discusses the previous metaphors further by evaluating them as easy or difficult situation, good Samaritan and minimally decent Samaritan scenarios, and discusses when there is a requirement to help.

1. Easy vs. Difficult, Long-term vs. Short-term

Thomson discusses cases in which it would be morally indecent to detach a person from your body at the cost of their life.

-        Example 1: Violinist. Thomson refers to the violinist example where you wake up to find yourself attached to a famous violinist against your will. Being attached from your kidney to the violinist’s heart is keeping the violinist alive. In the initial example, you must remain attached to the violinist for 9 years so that the violinist may live. In this modified scenario, the violinist needs you only for an hour, and being attached to the violinist wouldn’t affect your health. Thomson suggests that in this scenario, it is unjust to disconnect yourself even though you did not consent because you make little sacrifice to keep another alive. (60)

Water is one of the most important parts of the success of life on earth. The fact that water is polar gives it properties that a lot of other liquids don't have. One of these properties is cohesion, it is the ability of water molecules to hydrogen bond to each other. It allows water to stick together and be tugged through plant xylem via negative pressure. The cohesion in water gives it a tensile strength that rivals other substances that are much more solid. In addition to cohesion, water molecules are also good at adhesion. Adhesion is the property of water that allows it to bond to other polar surfaces. Adhesion is the reason that water can "walk" up a thin capillary tube. The ability to move up a tube also has to do with the surface tension of the water. As water climbs up the walls of the glass tube, the surface area of the water increases. The force of surface tension wants to decrease the surface area of the water, so it tugs the water up in order to maintain a more stable surface area. All of these forces play a role in moving water up a tube, however they are all stopped eventually by gravity.

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.

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.

            Using a dynamic approach to modeling disease allows for a vast amount of advantages when addressing public health problems. Many results of mapping and modeling a progressive disease demonstrate epidemiological aspects that can be useful in discovering why the disease came to be and how it could be treated. Additionally, models can demonstrate the efficacy of routine screening and other forms of preventative care for those who are more at risk of certain diseases and conditions. Identifying important forms of upstream prevention can drastically reduce the spread and severity of disease. Modeling can also be useful in discerning the relationships between multiple interacting diseases, shedding light on feedback loops that amplify symptoms and chronic conditions. Disease modeling can also be used on a single patient level, where certain input signs and symptoms can lead to an output that would not have been reached by traditional means. Overall, the benefits of using simulation dynamics for modeling disease are immense, and can steer public health officials and medical practitioners to a sound and logical answer to questions that seem to have none.

The stomata serve a vital function to plants as a whole. They are the structures which allow transpiration to occur, keeping the plant from drying up by promoting water flow. The stomata are small openings on the bottom sides of leaves. These openings lead into the spongy mesophyll, where gas exchange occurs. This gas exchange allows the plant to photosynthesize as well as perform transpiration. In order to prevent excessive water loss in the case of a drought the stomata are bordered by guard cells. When water is plentiful the guard cells fill with water, causing them to open. When water is scarce however, the guard cells lose water and shrink. This shrinkage causes them to close the stomata shut, preventing further water loss of gas exchange. 

Due to the passive nature of water movement in plants, water has a very specific path that it must take through the plant. Water starts in the soil, where the roots absorb it into the system of the plant. From the roots, water travels through the root cortex and the root endodermis. Once it passes through these structures, the water finall enters the xylem, which acts as a long tube that runs directly through the plant. Transpiration in the leaves helps to pull water through the xylem up the stem. This is where the water reaches the leaf mesophyll, at which point it evaporates and exchanges out of the leaf through the stomata. This evaporation helps to pull more water up into the leaf. 

Camellia Japonica is found in mainland China, Taiwan, South Korea, and southern Japan. It can usually be found 980-3,610 feet above sea level. It usually grows from 4 to 19 feet tall but has been known to grow up to 36 ft. It usually flowers between January and March. When found it the wild the flowers of the Camellia tend to have six to seven white petals about 4 cm long, however red petaled variants can also be found. It is known as the “Common Camellia,” the “Japanese Camellia,” or the “Rose of Winter.” It is also the state flower of Alabama. This plant is usually found as a shrub, however proper pruning can help the Camellia to form a tree. Wild Camellias can live to be 100-200 years old.

Step 1- The lungfish points it's head and mouth out of the water. It then opens its mouth using the sternohyoideus and expanding its buccal cavity taking air into its mouth. The mouth remains open.

Step 2- The lungfish opens its glottis allowing the air in its lungs to exit out its mouth mixing with the air in its buccal cavity. The air is able to exit the lungs through elastic recoil and contraction of smooth muscles.

Step 3- The mouth closes and using brachial constricting muscles and the lungfish forces the mixed air into its lungs

Step 4- The lungfish closes its glottis and hold the air into its lungs. The lungfish then submerges.

The plastid is an organelle found in plant cells that is undifferentiated and takes on many roles depending on what the cell needs it for. In photosynthetic cells in leaves, the plastid is known as the chloroplast and its main function is to create sugar through the process of photosynthesis. In petals, the plastid turns into a chromoplast and is used to create pigments to color the cells. In roots, the plastid becomes an amyloplast which uses dense starch to sense the direction of gravity so the roots know where to grow. The undifferentiated plastid is very similar to a stem cell in which it contains the DNA to become any one of these organelles. One thing that makes the plastid different from stem cells is its ability to become undifferentiated again. Some plants are able to take the differentiated plastid like a chromoplast and turn it into an undifferentiated plastid so that it can perform another task. This remarkable organelle is just one thing that makes plants so spectacular, and successful.