Category: Sciences 2502

This reflective treatise attempts to explain the stellar nebular theory and evidence to support the same. Besides, the paper explores the unique feature of terrestrial planets of Earth, Mercury, Venus, and Mars. The same explores these features in the Jovian planets of Jupiter, Saturn, Uranus, and Neptune. In addition, the treatise discusses minor members of the solar system, such as the comets, asteroids, and meteors.

The stellar nebula theory

The stellar nebular theory outlines cosmological evolution and the formation of the solar system. According to this theory, dense and massive molecular hydrogen clouds formed the stars (Stanley 23). These hydrogen clouds were unstable gravitationally; thus, facilitated coalesces of denser and smaller plods within. As a result, these clumps collapsed and formed the stars.

As opined by this theory, the stars formed produced protoplanetary gas, which formed a disk around them. This gas is thought to have given birth to the planetary system as a result of the cooling effect on the disk, which then formed small dust grains. These grains turned into rocks and coagulated into planetesimals. As a result of violent mergers, the planetesimals produced terrestrial planets (Stanley, 34).

The main evidence coined to support this theory includes the discovery of dusty and gaseous disks surrounding protostars. It was observed that the dust particles within these disks grew in size over a period of time (Stanley 45). Besides, scientific evidence indicates that embryo mergers would result in the formation of small round bodies.

The same feature is present in the solar system, which is characterized by the presence of different planets with different sizes depending on the distance from the star.

Besides, as of 2012, the scientists have discovered seven hundred and seventy-eight extrasolar planets thought to have formed from the nebular process as smaller embryos merger in a continuous process over a long period of time. The discovery opened doors to further exploration that led to the discovery of the dusty and gaseous disks surrounding protostars (Stanley, 39).

Terrestrial Planets of Earth, Mercury, Venus and Mars

The first four planets in the solar system are often referred to as the terrestrial planets. Reflective, these planets have a smaller diameter and are solid. Apart from the Earth and Mars, the other two have no satellites. Venus has the longest sidereal rotation period of 243 days, with the Earth having the least of 24 hours.

In this classification, Mercury has 59 days to complete a single sidereal rotation, with Mars having 25 hours. Mercury, Venus, and Earth are having an almost equal density of more than 5, with Mars having the least density of 3.9. The four planets have craters with Mercury having the most. Mars has a higher volcanoes than the other planets. However, this red planet lacks continental drift present in the other three (Lewis 67).

The atmospheric chemical composition of Mars and Venus are very similar (Nature of the Universe: Terrestrial Planets, par. 6). All the planets have layers of gaseous carbon dioxide with Earth having the least since photosynthesis absorbed most of the carbon dioxide gas.

Unlike the planet Earth, the others have no active volcanic activities. Actually, the presence of volcanic features on their surfaces is due to the absence of continental drift (Nature of the Universe: Terrestrial Planets, par. 7). Thus, due to their almost similar sizes, mass ratio, density, and revolution period, these planets are classified as terrestrial. However, they vary in composition, climate, and surface (Simon 45).

Jovian Planets of Jupiter, Saturn, Uranus, and Neptune

Often referred to as the Jovian planets, Jupiter, Saturn, Uranus, and Neptune have rings and are all located outside of the asteroid belt (The Jovian Planets: Jupiter, Saturn, Uranus, and Neptune, par. 8).

Reflectively, these planets share some features such as high mass, low density, are gaseous with some of these gases existing in solid form, rotates rapidly, are far to the sun, have a very strong magnetic field, and have very thick atmospheres.

Besides, the planets are characterized by the existence of many satellites in their field. In addition, these planets have a larger diameter and exist as fluid bodies, which are basically supported by hydrostatic equilibrium balancing gravity and pressure. Jupiters interior has a larger proportion of metallic hydrogen as compared to that of Saturn. However, Uranus and Neptune lack the metallic hydrogen component in their interior.

The rest of the interiors of these planets consist of ice and rocks. Interestingly, Jovian planets have internal heat sources (The Jovian Planets: Jupiter, Saturn, Uranus, and Neptune, par. 9). They radiate more energy than they absorb from the sun (The Jovian Planets: Jupiter, Saturn, Uranus, and Neptune, par. 12).

All the Jovian planets have large magnetospheres filled with charged particles (The Jovian Planets: Jupiter, Saturn, Uranus, and Neptune, par. 14) and cause series of defined bow shocks on the solar wind. Besides their own satellites, the Jovian planets have shepherd satellites in their ring systems.

Apart from that of Saturn, the rings of the other Jovian planets are forward scattering (Lewis 67). In fact, that of Saturn is usually dark and appears to have spokes.

Asteroids, Meteors, and Comets

Often referred to as minor planets, Asteroids are metallic and rocky bodies revolving around the sun in the Asteroid belt (Lewis 89). Their eccentric orbits sometimes wander into the regions between Jupiter and Mars. They vary in composition, orbit, and size. Factually, Ceres is the largest asteroid with a diameter of 623 miles (Asteroids, Comets, and Meteoroids, par. 4).

Asteroids exist in types C, S, and M. Type S is relatively light as compared to type C. Johann Bode discovered Asteroids in the 18th century. The widely accepted theory on the formation of asteroids states that asteroids are pieces of matter that never coalesced to form a planet (Asteroids, Comets, and Meteoroids, par. 6). However, they are of low density.

Commonly referred to as dirty snowballs, comets have long visible tail extending from their nucleus. There are two types of comets, that is, short-period comets and long-period comets. Ice and dust in the form of ammonia, water, methane, and carbon dioxide complete the structure of a typical comet. Close to the nucleus of a comet is a bright cloud of gases and dust ejected from the nucleus (Lewis 103).

Moreover, meteorites are small chunks of stone that are capable of intersecting Earths orbit (Asteroids, Comets, and Meteoroids, par. 10). Meteorites vary in sizes.

Meteoroid becomes meteor on invading the Earths atmosphere. However, when the same fails to disintegrate and fall on the Earths surface, then it becomes a meteorite (Asteroids, Comets, and Meteoroids, par. 19). Generally, meteors are believed to be originating scattering asteroids on collision with the asteroid belt. Asteroids are the largest among the three, with meteorites being the smallest.

Works Cited

Asteroids, Comets, and Meteoroids 2012.

Lewis, John. Physics and Chemistry of the Solar System, New York: Academic Press, 2004. Print.

Nature of the Universe: Terrestrial Planets 2010.

Simon, Seymour. Comets, Meteors, and Asteroids, New York: HarperCollins, 1998. Print.

Stanley, Ford. Notes on the nebular theory: in relation to stellar, solar, planetary, cometary and geological phenomena, California: Trubner, 1985. Print.

The Jovian Planets: Jupiter, Saturn, Uranus, and Neptune 2011.

The article Differences in the concentration of ergosterol isolated from strains of Monilinia fructicola resistant to demethylation inhibitor and susceptible strains: understanding the Mona element presents an overview of the scientific experiment. The experiments basis is the infestation of peaches and nectarines by the fungus Monilinia fructicola (Hulse, 2021). This creates economic problems in the Southeastern United States, where the cultivation of these fruits occupies a large production sector. The articles main topic is the identification of resistance factors of Monilinia fructicola to demethylation inhibitor fungicides, which are designed to protect the fruit from infestation. Fungal isolates were tested under three different conditions: without Mona element without resistance to fungicides and with Mona element with and without resistance. The tests were carried out to determine whether the fungi of Monilinia fructicola use a sterol other than ergosterol and an enzyme other than 14-a demethylase for its synthesis.

To determine the studys statistical results, the data were analyzed using Microsoft Excel. Tests such as Students t-test and ANOVA table analysis were then performed. They determined if the ergosterol concentrations differed between samples containing and not containing the Mona element (Hulse, 2021). The results of this study were unexpected for the researchers. A group of isolates without the Mona element but susceptible to DMI fungicides produced a much higher ergosterol concentration than expected because they do not have the promoter sequence for 14-demethylase production. Thus, their resistance to the DMI element could be explained by a mutation in the CYP51 gene or by resistance developed in another way.

The authors of this article put forward two other hypotheses that could explain the immunity of the fungi to the DMI element. The first is that resistant strains use a different enzyme in the sterol ergosterol synthesis pathway. The second is that the fungi use a different promoter in this biosynthesis pathway (Hulse, 2021). Thus, the researchers concluded that the resistance is explained by using a different enzyme from 14-demethylase for ergosterol synthesis by Monilinia fructicola fungi. This article left an extensive field for discussion within the scientific community and further research into the resistance of fruit-infesting fungi to fungicides.

Reference

Hulse, J. (2021). The difference in ergosterol concentrations extracted from demethylation inhibitor-resistant and susceptible strains of Monilinia fructicola: understanding the Mona element. Journal of applied plant protection, 10(3), 121-130. Web.

General Information

The humpback whale is a typical representative of cetaceans, which despite their underwater life, are also mammals. In evolutionary terms, whales are ancient mammals that returned to life underwater, which means their bodies were adapted to high pressure. Humpback whales are thought to inhabit all of Earths oceans except the Arctic due to low temperatures. Humpback whales have folds of keratinous skin along their entire body, which spread out during feeding to increase their water intake. The life cycle of such whales is closely tied to seasonal changes which provoke waves of migration. Humpback whale offspring conceived in winter feed on their mothers milk even underwater. The feeding mechanism of humpback whales is based on filtration, during which substantial cubic meters of water are absorbed by the animal, and small fish, plankton, and crustaceans remain on the long whale whiskers.

Skull structure

The skull of the humpback whale is asymmetrical and robust, which is necessary to balance the animals heavy head. Part of the lower jaw is fused with the upper, and the latter has no teeth. At the same time, the lower jaw is slightly forward so that the front part of the animals body ends as if rounded. The depressions under the eyeballs are small, as are the eyes themselves, which is obvious, given the underwater life of the mammal. It is noteworthy that in the structure of the humpback whale brain, there are no visible differences from other whales, but the olfactory areas are strongly reduced, which indicates that whales have no sense of smell.

Structure of the postcranial skeleton

The name of this whale species is fully justified by its external appearance: the structure of the spine creates a similar hump in the dorsal region. There are wart-like growths all over the body, which are probably rudimentary hair follicles. The humpback whale has two pectoral fins, each represented by four undeveloped fingers of different lengths and one caudal fin. The maximum body length of such a whale is 19 meters, and the whale can weigh up to 40 tons. The skeletal bones are represented by spongy material, and the bones are densely impregnated with fat. This feature is dictated by the need for enhanced thermoregulation of marine animals. The long spine consists of 98 vertebrae divided into four sections. The spine flattens in the lumbar area, which is necessary for balancing the heavy body. The hind limbs are wholly reduced, but the rudimentary remains of the pelvic bones, which have no connection with the spine, are preserved.

A detailed study of the regularities of chemical molecule interactions at both the molecular and electronic levels allows summarizing the available knowledge and identify key trends qualitatively. Among others, it is of research value not only to generalize but also to identify the potential of reaction pathways and bias effects initiated by catalysts or other added substances. Finally, an excellent demonstration of personal knowledge and competence are assignments in which the student is asked to propose organic synthesis schemes using only the substrate as the source. Summarizing all of the above, it is essential to note that solving such assignments is a sound academic strategy for learning chemical sciences. At the same time, aromatic substances that have a benzene ring in the molecular structure have the highest stability due to the balanced electron density throughout the sp²-hybridized ring. Consequently, it is the study of aromatic substances that is of great importance to all organic chemistry. Therefore, this essay consistently discusses the answers to the four proposed assignments on the topic of organic synthesis. This paper is valuable and relevant material not only for the author but also for all students interested in finding answers to organic synthesis questions.

First of all, it should be said that aluminum chloride, also known as Lewis acid, is often the substance that initiates and catalyzes the reactions of organic addition of electrophilic substituents to the À-electron cloud. The addition of foreign atoms or atomic groups causes the electron density of the cloud to shift and move throughout the ring until maximum stability is achieved. The methoxy group in this assignment is a substituent that transfers electrons into the ring and thus increases the overall electron density of the aromatic ring. In addition, the final position of the substituents must be found, including the steric effect that prevents the effective course of chemical reactions. Concerning anisole, Lewis acid initiates addition at the ortho- and para-positions, and therefore it should be expected that the methoxy group nucleophile to join at both positions, forming two reaction products: 2-methoxyacetophenone and 4-methoxyacetophenone, as shown in Figure 1. In this case, 4-methoxyacetophenone has a higher yield due to the optimal location of the substituent minimizing the steric effect.

The second assignment, which assesses the students academic competence, examines possible ways of synthesizing one organic substance from another. More specifically, for this essay, phenol as a source and 2-allyl-4-chlorophenol as the final product were chosen. It is already clear from the product name that nucleophilic substituents at the ortho- and para-positions must be added to the benzene ring. For this purpose, a series of Friedel-Crafts organic mechanisms with Lewis acid as a catalyst should be used (Ashenhurst, 2021). It should be noted, nevertheless, that the halogen in the added salt should correspond to that in the nucleophile, as shown in Figure 2. Again, positions 2 and 4 were driven primarily by stabilizing the electron density of the À-cloud and minimizing the steric effect. Thus, two nucleophilic substitution reactions are sufficient to obtain 2-allyl-4-chlorophenol from ordinary phenol.

It is also imperative to be able to obtain complex organic substances from simpler ones since this task has practical applications. For example, if a particular substance is not enough in the laboratory, it can be obtained by organic synthesis reactions and then used as intended. The third task belongs to this category because it asks about the potential pathway for synthesizing complex compound A  Figure 3  from anisole, shown in Figure 1. It can be seen that the number of aromatic rings has doubled, with only the left corresponding to the original anisole. Hence, it is appropriate to use the Friedel-Crafts reaction to attach a massive nucleophile to the para-position with the corresponding Lewis acid. Once the intermediate molecule is obtained, the double oxygen bond must be reduced so that a hydroxyl group is obtained from the carbonyl group (Kennepohl, 2019). A semi-anionic hydride acting as a nucleophile transferring hydrogen to the carbonyl carbon can be used for this purpose. The final processes are shown in Figure 4.

Finally, in the organic chemistry section, the use of instrumental methods of analysis that allow qualitative identification of compounds is of great importance. NMR forms the basis of such methods since it gives a highly accurate and sensitive understanding of the nature of the molecule. NMR performed on ¹³C isotope nuclei generally allows suitable identification of the parts of the substance, and especially the aromatic components. As shown in Figure 5, the specific signal value for the same carbon atom surrounded by different groupings also varies. More specifically, the quantitative signal measure  ppm  decreases in the following sequence: ketones, aldehydes, acids. The reason for this shift, caused by the carbon environment, may be the amount of free hydrogen in the neighborhood of the selected carbon atom. More specifically, in ketones, carbon has five alpha hydrocarbons  three on the left and two on the right  in aldehyde only three  all on the left  and finally, in acid, carbon has only two alpha hydrocarbons  both on the left. Thus, the lower the number of hydrocarbons a selected carbon has, the lower the ppm number for it. This is not surprising since the chemical shift value is based on the number of equivalent hydrocarbons (Clark, 2020). The more hydrogen surrounding the atom, the more to the right it shifts on the horizontal axis. The figure below confirms these beliefs. Thus, using personal chemical knowledge and competence can solve complex problems.

References

Ashenhurst, J. (2021). EAS reactions (3)  Friedel-Crafts acylation and Friedel-Crafts alkylation. Master Organic Chemistry. Web.

Clark, J. (2020). Interpreting C-13 NMR spectra. LibreTexts. Web.

Kennepohl, D. (2019). Reduction. LibreTexts. Web.

Introduction

In the Ötztal Alps, right on the border of Italy and Austria, a man who lived more than 5 thousand years ago was discovered (Kristensen 170). He existed when our civilization was in the initial stages of its formation. More than 30 years have passed since the discovery, but its study continues. At first, Otzi was mistaken for a dead climber: the body was only half pulled out of the glacier, but it seemed that he died relatively recently. The Ice Man has become a unique source of information about how the distant ancestors of Europeans lived and what they ate and wore. As a result of the excitement among the public and scientists after the discovery of Otzi, a new historical discipline was born  glacial archaeology.

What Is a Mummy

A mummy is a body that stores soft tissues (skin and dehydrated muscles) for a long time after death. Mummification can be natural or intentional (for example, the embalming of Egyptian pharaohs). The absence of conditions for rotting contributed to the natural preservation of mummies in the highlands, such as the Ice Man, who froze in the Alps around 3300 BC (Fleur). In this case, mummification became possible due to the unique climatic conditions that allowed the body to be preserved. Cold can retain corpses for thousands of years. Despite thousands of years spent at a great height above sea level, mummies retain parts of clothing, facial features, and even tattoos on the skin.

Analyses/Technology Used to Examine the Remains

Today, the set of methods and approaches used when working with mummified remains depends on the tasks facing researchers. Some individuals (such as the Ice Man) are usually studied more thoroughly and scrupulously using specialized research technologies. In the projects first stage, the radiography of mummies, macroscopic examination of body tissue samples, and microscopic examination of histological sections obtained after tissue rehydration are carried out. Paleontological and fingerprinting studies follow this, identification of insect remains, textile analysis, and radiocarbon dating. In addition, facial reconstruction is performed on the skull for individual individuals. After the discovery of the Ice Man, work began on improving the methods of minimally destructive tissue sampling and analyzing them.

Analyzing Physical Remains

Careful study of mummies allows scientists to even restore their appearance. For example, the condition of teeth and joints can determine the age of a person, as well as height and weight. For example, the height of Otzi was 165 centimeters, and he weighed only 50 kilograms; at the time of his death, he was about 45 years old. (Fagan and Durrani 43). The condition of his muscles indicated that Otzi was used to moving over rough terrain, perhaps grazing sheep on high-altitude pastures. Analysis of the contents of the stomach and intestines allowed scientists to determine the diet of the deceased. The Ice Man last ate eight hours before his death (Kristensen 169). He had two types of meat: chamois and deer (most likely dried), bread, and roots.

Artifacts Associated with the Ice Man

Among the artifacts associated with the Ice Man were his clothes. Otzi was dressed in a whole set of things made of the skin of various animals (sheep, goats, and cows). He wore shoes with wide soles, most likely specially designed for movement in the snow. A grass layer was found inside the shoe, which additionally warmed it. On top of all this, the deceased man of the Copper Age wore a cap of brown bear skin with a leather strap. Otzi had a whole set of things with him: first, archaeologists were struck by a perfectly preserved copper axe with a 60-centimeter handle made of yew (Kristensen 171). The largest artifact was a wooden yew bow with a length of 182 centimeters, and the object was still not finished (Fleur). The other items were more primitive: a stone knife, a flint scraper, and a bone awl.

Unanswered Questions

The question of the circumstances and cause of the death of the Ice Man remains unanswered. For a long time, the generally accepted version was the version proposed by Konrad Spindler; according to the archaeologist, Otzi froze to death, having fallen at an altitude of 3210 meters in a snowstorm (Fleur). In 2001, during an X-ray examination of the mummy, a deeply stuck arrowhead was found in his left shoulder (Fleur). In addition, traces of the blood of four people were found on various objects at once. The most popular and plausible versions are murder and death from falling into an ice storm. However, the circumstances and cause of death are still unknown.

Conclusion

In the countries of Northern Europe, in Switzerland, as the ice melts, more and more artifacts lost millennia ago began to return to the surface of the earth. Due to global warming, scientists began to make numerous finds frozen into layers of snow and ice. Studying this type of natural mummy required new technologies for analysis, which led to the emergence of glacial archaeology. Otzi from the Ötztal Alps remains an unsurpassed discovery so far. However, it can be assumed that many historical discoveries are still waiting for glacial archaeologists.

Works Cited

Fagan, Brian, and Nadia Durrani. The Many-Voiced Past. In the Beginning: An Introduction to Archaeology, Routledge, 2020, pp. 42-56.

Fleur, Nicholas. Tiny Brains of Extinct Human Relative Had Complex Features. New York Times, Web.

Kristensen, Gustav. A New Interpretation of Otzi, the Iceman. Sustainability in Environment, vol. 4, no. 3, 2019, pp. 165-171.

Contact lenses have been around for a long time, since 1948, and are extremely popular as a means to temporarily or permanently replace glasses for over 125 million users worldwide. Contact lenses are primarily ocular prosthetic devices for vision correction but are also used for cosmetic or therapeutic reasons to change eye color. This study aims to determine if there is contrast sensitivity between clear and colored eye lenses depending on lighting conditions.

Background

There are two types of contact lenses  hard and soft. The Rigid Gas Permeable (RGP) are hard and difficult to put in but are durable and clearer, but only compromise 2% of all wearers. The rest are soft lenses. There are temporary lenses, regular soft lenses that allow oxygen to pass through for short-term wear, and silicone hydrogen lenses for long-term wear, compromising a large portion of wearers. Contact lenses aim to correct refractive error, which ultimately cause the focus and vision problems. However, contact lenses are not fully safe, given the risk of microbial infection.

Much of the concepts around quality vision is based on contrast sensitivity. Contrast is converted to light scattering and light scattering is affected by contact lenses. For example, multifocal contact lenses are likely to decrease contrast sensitivity and lead to poorer quality. Studies previously indicated different results on CS for single focal lenses. Given these discrepancies, the researches aim to find out the CS and visual quality for different lenses in the respective light conditions.

Methods

For this study, 34 university students were selected. They had to pass multiple criteria including no disease or conditions. They had to pass unassisted acuity tests and fit on the different lenses. The researchers took time to ensure that vision was not influenced, so patients were given time of at least 2 hours to adjust to light or lens changes. The patients eyes were randomly selected to fit the lenses. Visual acuity was measured using a tumbling E chart at distance of 6m, while the Pelli Robson chart was utilized for CS.

Data Analysis and Considerations

Given that the study involved humans, ethical design and approval was necessary which was given by the Ethics Committee of Zahedan University of Medical Sciences. As for data analysis, ANOVA or analysis of variance is a statistical test used to separate observable variance data into different compounds. A one-way ANOVA helps to get the relationship between groups of data and variables. Therefore, given that the research aim is to determine the effect contact lenses on CS, this common statistical data analysis test is appropriate for this type of research.

Results

These are the fundamental results discovered as part of the study. Visual acuity did not change and was not expected to given that students were tested previously to being selected. So, CS did seem to decrease when contact lenses were applied. This was most evident in poor lighting conditions such as darkness and glare. However, no significant differences were ultimately found between clear and color lenses in regard to CS. Lighting conditions affected CS reduction for contact lenses in all circumstances.

Discussion

Studies of other researchers largely match Mahjoob and Heydarian (2021) in determining the CS drop attributed largely to soft contact lenses. Various factors may have an impact, but since this study excluded people with astigmatism and used temporary lenses, corneal edema is the most logical explanation given the continuous change of lenses.

One of the limitations was that not measuring the corneal thickness, as by doing so the corneal edema effect could have been understood better. Furthermore, the similar CS between clear and colored lenses could be to the large diameter of the pigment-free optical zone in the colored contact. This both suggests ineffectiveness of optical parameters but confirms active role of corneal edema. Overall, the study found that clear and colored lenses reduce CS, this has both real-world impacts and contributes to the body of literature which indicate potential influences such as edema, pupil size changes, and other elements that could the effect on visual contrast.

Reference

Mahjoob, M., & Heydarian, S. (2021). Effect of contact lenses on contrast sensitivity under various lighting conditions. Journal of Ophthalmic and Vision Research, 16(4), 538543. Web.

A spiral galaxy is one of three types of galaxies studied and documented by Edwin Hubble. Spiral galaxies are apparently the most common in the universe and have a characteristic spiral contour; that is also the characteristic feature referred to in their name.

The spiral shape is usually constituted of arms enfolded around a dense core of galaxy forming matter and bodies that include dust, among others. The most obvious feature that can be seen from the unaided eye; that suggests that the earths universe is a spiral galaxy is the Milky Way.

The Milky Way is the earths home galaxy; and has the features of a spiral galaxy that include a galactic core, which constitutes of swelling of extremely old stars that are placed to surround an extensive black hole. The black hole on the Milky Way is the space between the arrangements of stars, in which the gravitational attraction is so immense it cannot allow the escape of any object.

The black hole itself consists of an immense concentration of mass; that results from the death of an expansive star, arguably ten times bigger than the sun. This mass gives it the capability of imposing gravitational pull on the objects around it, including light that explains the reason as to why the black holes are dark. This is the case because the gravitational pull that results is so immense that it cannot even let light pass through it.

The other characteristic of the milky way that qualifies it to be a spiral galaxy is the distinctiveness of the bulge when the milky way is viewed from the side. The Milky Way also has arms surrounding the core; that is constituted of stars much younger than the ones forming the galactic core.

The Milky Way has a halo of stars believed to be older than the rest; that is arranged in globular clusters that are the dense packs of stars visible from the earth, though they may appear like single masses. The bar shape of the milky way also qualifies it to be a barred spiral galaxy, as its core takes a bar-shape that causes the bulge looks like peanut when viewed from one side.

The other fact that distinguishes the Milky Way to be a spiral galaxy is the configuration of the arms that places it within the Sb classification. Apart from the earths Milky Way, are other spiral galaxies that have been located within the earths universe acting as a proof that the earth is housed by, and in a spiral galaxy.

If the sun and solar were located near the center of the galaxy, it would mean that they would fall close if not within the black hole. Due to the immense gravitational attraction of the black hole that attracts even light, the suns light that is radiated onto the earth would significantly be reduced.

The situation would also lead to partial darkness due to the gas and dust that forms a major part of the galaxies; that would block the light and heat radiated by the sun onto the earth.

In the case that the solar system was to be placed in this position; would mean that the earth temperatures would significantly become lower than the present ones; the light shed on the earth during day time would be very greatly reduced; and the life on earth that relies on the suns heat and light, would not exist within the environment.

This would also create the need for more sources of lighting and heating; so as to provide for the lighting needs and provision of temperatures that are homely to the inhabitants.

A globular cluster is a spherical group of stars that move around a galactic core as a satellite. The components of the cluster are usually held very tightly together; by the gravitational force that is resultant, therefore giving it the spherical form and high stellar densities.

If the earths sun and solar were placed near the center of a large globular cluster, it would mean that the earth environment would appear like it is lit by a number of suns, and the shadows formed by the blockage of the suns light on the earth would also increase.

The effect of this would be; unstable, increasing, and decreasing the lighting and temperature conditions; that would be experienced on the earth. These variations would further affect the animal and plant life that is harbored in the environment.

Molecular clouds are composed of clumps, irregular masses, bubbles, and filaments that are placed in chemically rich surroundings. An example of molecular clouds is the Taurus and Orion molecular clouds. In the case that the sun was placed at the center of a dense molecular cloud, the light from the sun reaching the earth would greatly reduce, leading to decreased visibility conditions on the earth.

The molecular cloud would also act as a sheltering mass that would reduce the amount of heat and light reaching the earth, which in turn would lead to varied earth temperatures, which would further result in different plant and animal life within the environment.

The causes for the redshifts that indicate velocity recession results from the fact that light from moving objects; appears to possess varying wavelengths that are determined by the relative change of position of the source and the observer. In the case when the object is moving further, red waves with a longer wavelength than when the light was emitted show the instance of a redshift.

The reverse is a blueshift that is experienced when the source of light is approaching, and this takes place due to the fact that the wavelength of the light is shifting from longer to shorter measures. In the different cases, the wavelength shifts lead to an apparent variation in the speed of the light in question, and that is why the slow-moving galaxies seem to move at massive speeds.

The universe expansion phenomena were discovered by Edwin Hubble in 1929, and in recent discoveries, it was documented that if the universe were finite, then the gravitational attraction forces would lead to the collapse of the entire universe. Discoveries identified that the spectra of light from many of the bodies in the universe were increasing, acquiring longer wavelengths, also referred to as redshifts.

Due to the constantly expanding universe function, the universe will eventually, after these many years, take the open, flat or closed universe shapes. The result would later be that if the universe expanded, forming an open or flat form, it would slow to an expansion rate of zero after a long time. However, if it were to take the closed expansion form, it would later reach the maximum measure and collapse on itself, probably leading to another big bang.

The force that slows the expansion in each case is the gravitational pull. The effects of the expanding universe would include reducing temperatures that would later reduce to levels that cannot support life. The distance between different galaxies would increase to the extent that different clusters would not experience each others experience anymore.

The supply of gases needed for the formation of stars would get exhausted, and the available ones would cease to shine. This means that in a few billion years in the future, the habitation of the earth would be impossible, and the universe would turn dark and blank.

Genetic research has expanded the bandwidth of opportunities for addressing an array of issues associated with managing the threats of genetic mutations and their negative outcomes. However, with the rise in genetic research, the discovery and further use of genetically modified organisms (GMOs) have occurred (Seralini 2). Though GMOs have a certain potential as the path toward understanding the mechanism of genetic predisposition and change, its disadvantages entailing threats to peoples health, suggest that GMOs must not be used in food production.

The adverse effects of GMOs have been debated quite heavily over the past few decades. Although the lack of consistency in the negative impact that GMOs may produce is often viewed as an argument in their favor, it is, in fact, the evidence against GMOs (Napier et al. 564). Namely, since the impact of GMOs are largely unpredictable when they are consumed by individuals, the threats that GMOs pose are too difficult to manage, hence the need to exclude them from the food industry.

Additionally, the issue of the toxicity of GMOs needs to be addressed. Research indicates that many GMOs have impressively high toxicity rates (Seralini 3). Though the specified outcome is described as long-term, the accumulated effect of the extended use of GMO-rich products is likely to cause noticeably adverse changes in public health (Seralini 2). Therefore, GMOs represent a major threat that must be contained.

Finally, when examining the side effects of GMOs as food constituents, one must mention the lack of consistency in their nutritional value. Namely, Napier et al. research indicates that many GMO-containing products expected to manage issues such as the lack of Vitamin A have been stuck in development limbo (563). As a result, the current impact of GMO-based products is still largely under-researched, leading to poor nutritional value in GMO-based products.

Despite certain benefits, particularly the opportunity to enhance crops resilience, GMOs pose a massive threat to peoples health due to the unpredictability of their influence, hence the need to exclude them from food production. Being heavily under-researched, the impact of GMOs also hinges significantly on individual factors, such as the presence of specific allergies, in individuals, which means that mitigating health-related threats of GMOs completely is impossible. Thus, GMOs must not be used as supplements or substitutes for specific products in the food industry.

Works Cited

Napier, Johnathan A., et al. The Challenges of Delivering Genetically Modified Crops with Nutritional Enhancement Traits. Nature Plants, vol. 5, no. 6, 2019, pp. 563-567.

Seralini, Gilles-Eric. Update on Long-Term Toxicity of Agricultural GMOs Tolerant to roundup. Environmental Sciences Europe, vol. 32, no. 1, 2020, pp. 1-7.

Introduction

Wildlife is always deemed to be of great significance economically, ecologically, environmentally as well as culturally. It includes a wide range of species from amphibians, insects, birds to mammals. Thus, there is no doubt that there are some organisms that are native while others were introduced or re-introduced to their current habitant (Day, Klingler & Bloomberg 283). The essay is an in-depth examination of five wild animals that exist in the United States of America. These animals are Red Fox (Vulpes vulpes), Northern Harrier (Circus cyaneus), Black and Yellow Garden Spider (Argiope aurantia), Northern Copperhead (Agkistrodon contortrix mokasen) and American Bullfrog (Rana catesbeiana).

To be able to cover these species adequately, the following will be established:

• Are the species, being studied, native or introduced in that environment?
• Describe their physical characteristics in terms of color as well as specific differences between the sexes.

Additionally, the issues regarding the species habitats are adequately tackled. This is attained by establishing their local habitat as well as their habitat range, their ecological role, the types of food they eat and other relevant relationships such as parasitism, mutualism are brought to light. The species category under IUCN is also brought to light. At the same time, discover life cycle of these species and life span as well as how they coexist with people.

Red Fox (Vulpes vulpes)

According to Rue (72), Red fox is the largest of animals that is considered as true foxes. This species is in the family of Canidae which is comprised of wolves, dogs and coyotes. These animals are characterized by an orange or red fur. Red foxes have white fur on their chest as well as beneath their neck. The tail is usually fluffy and white at the tip. The ears are black and pointed. Their legs are colored black. The animal is about three feet long and weighs 10 pounds.

As suggested by Clapham (122), Red fox inhabits a greater part of the United States as well as Canada, but there is no record to show that they ever existed in Alaska and Texas. According to IUCN, it is categorized as Least Concern for extinction and named as worlds worst alien invasive species. They have a wide range covering approximately 70 million square kms including wood lands, farmland as well as prairies.

Historically, red foxes were being preyed by lynx, wolves, and bobcats but due to the reduced number of these predators, people became the major predator hunting these animals for various reasons, such as sport hunting, as well as for their fur or by farmers in protecting their crops and livestock (Rue 121). It is thus no doubt that red fox has a long association with mankind. This can be depicted in human folklore as well as in myths. Red foxes are opportunistic feeders whose feeding pattern varies with season as they eat everything available during some period. Generally speaking, this species is omnivorous eating fruits, grasses and berries. They also feed on birds, insects, small mammals. They can investigate over five miles looking for food despite the fact that they are not hungry. Surplus food stuffs are hidden to be consumed later (Clapham 54).

With regards to reproduction, red foxes reproduce only once a year during spring. Female estrus lasts for 21 days during which the male mates with her for a number of days in burrows during which there is at least an hour of copulation tie. The gestation period is approximately two months. Prior to littering, the female/vixen will get two den ready. The litter size ranges between 4 and 8. As the female is nursing the litter, males look for food. Within a period of about 2 weeks, the kits open their eyes, and 4 days after, lower teeth start emerging. The juvenile takes a period of six to seven months, and then, the adulthood comes. It has been established that in their natural habitat, the red foxes attain a maximum of five years and fourteen while under captivity (Rue 65).

These mammals are nocturnal and can hear voices in lower frequencies. They stalk their prey just like the cat does, then pounce and chase. Dens are utilized for reproduction reasons. Red foxes sleep in open environment using their tail to save warmth (Clapham 23).

Northern Harrier (Circus cyaneus)

Also known as marsh hawk, the bird is between 17 and 24 inches with a wing span ranging from 3.5 to 4.5 feet weighing between 12 and 18 ounces. Males are typically smaller than females. This bird inhabits North America apart of Asia as well as Europe. They are commonly found in open areas, wetlands, cultivated regions, meadows, grasslands and tundra. New Jerseys costal marshes provide northern harrier with the desire habitat. They are typically found in New Jersey, Texas, and Alaska and known to wander over 100 miles in a day in search of food (Ferguson-Lees & Christie 97). The species has facial characteristic that resembles an owl. Males are grey and white above and below respectively and have a wingtip that is black as well as the trailing edge towards the wings. Males white breast has a rusty spotting. Females are brown and buff colored above and below in that order. Contrary to their males counter parts, females under-wings are dark and the black wingtip is obscured. The juvenile looks like the females.

They feed on a variety of food including insects as well as small mammals. It is worth mentioning that the bird itself is a prey to skunks and raccoons, which steal its eggs, as well as some birds of prey, feral cats, and red foxes. The acute eye sight makes them a perfect hunter that can ambush and grab their victim suddenly. Due to their sharp eye, they are able to spot their prey. As they circle the area once satisfied with their ambush, they swoop downwards and grab their prey using their sharp claws. Circus cyaneus has coexisted with mankind for a long time. For instance, in Europe, it was believed that when northern harrier perched on once house, 3 people will lose their lives (Ehrlich, Paul Dobkin & Wheye 162). Some Native Americans considered this bird to be a good luck. When it appears during marriage day, it is a sign of a long and happy marriage relationship. Majority of farmers like these birds because they help control pests, for instance, eating eggs of quail, and insects that could have destroyed their crops.

According to Ehrlich, Dobkin & Wheye (231), the birds are migratory and native to the region. Due to decline in population as a result of predation and habitat destruction, the species has been categorized as being endangered. They attain reproduction maturation at the age of 1 year. Females lay 3 to 6 eggs depending on the availability and abundance of small rodents. Incubation takes approximately one month. While females sit on the eggs, it is the responsibility of males to hunt for food and take some to the females. The species can live up to approximately twelve years.

Black and Yellow Garden Spider (Argiope aurantia)

According to Gertsch (147,) other common names associated with the species, Black and Yellow Garden Spider, include writing spider or corn spider. Black and yellow garden spiders are mostly found in forty eight states of the United States of America. Additionally, they can be found in regions such as Mexico, Canada and Hawaii. The species is uncommon in the Rocky Mountains as well as the Great Basin but can be found in Costa Rico. The abdomen and the caphalothorax of the insect are colored black and yellow, respectively. It is worth noting that females are larger in size than males ranging from 19 to 28 mm and 5 to 9 mm, respectively.

Through its association with mankind, it has been established that Argiope aurantia is harmless to human beings, and for that reason, it coexists with people in peace. The spider also helps man in predating on disturbing insects. The representatives of this species are typically carnivores and employ a strategy of waiting for their prey in the web which is zigzag shaped. Once the prey appears in the web, it is deemed to be captured by the spider and injected a venom in which makes the prey immobile. Then the spider wraps it and store somewhere to be eaten later. The prey can be flies, moths, beetles, wasps and mosquitoes (Gertsch 203). The species is native in most part of the country, but the most widely introduced in California. These spiders inhabit gardens as well as old fields. Their success in California is attributed to their ability of avoiding predators. They are eaten by birds, species of wasp such as mud daubers, lizards and shrews.

With regards to reproduction, they breed only once per year. For reproduction purposes, males are the ones searching for females. As a sign of interest to reproduce, the male idividuals go plucking strands on the web constructed by a female. It is worth noting that after mating, the male dies often not consumed by the female. Eggs are laid at night on silky material and covered. The sacs produced range between 1 and 4 each having close to 1,000 eggs. The female protects the sac until the spring because it is during the spring that the juveniles come out. During the period of growth and development, they shade the exoskeleton. At time, they may lose their legs but are able of regenerating them. Moreover, concerning the status of the species, Herbert, Levi & Strekalovsky reveal that the representatives of this species are listed as endangered/threatened (72).

Northern Copperhead (Agkistrodon contortrix mokasen)

The venomous snake called Northern Copperhead is found statewide apart from barrier islands living in wetlands, edge areas, and forests. Agkistrodon contortrix mokasen is found in regions such as Illinois, Alabama, Georgia as well as Massachusetts. For that reason, its habitat is wide. The species can be also found in open areas made up of rocks which they use for cover. According to Herrmann (par. 1), the snake has not yet been categorized by the federal government, nonetheless, in the state of Massachusetts, the snake has been listed as endangered.

The snake grows to approximately 76 cm in length, the head is characterized by unmarked copper color head and reddish-brown body. They are thick in body having keeled scales. An organ which is sensitive to temperature is located on sides of its head. The juveniles are 7-10 inches being greyer that the adults which fade when they reach the age of 3-4 years. They are sexually dimorphic, males being smaller than females. Sexual maturation is attained at age of 4 years (Northern copperhead (Agkistrodon contortrix mokasen).). They have breeding seasons that last from August to October and from February to May. Using the tongue, males seek for sexually active females. Once this is done, he starts to rub his head on the ground after courting. When sufficiently stimulated, the female avails the cloaca. They mate for a period of between 31/2 and 81/2 hours. During mating, the male releases a special pheromone which makes the female unattractive to other males. It takes between three and nine months for young ones to pass the larval stages. The life span of this reptile is about 18 years (Herrmann par. 4).

It is worth noting that adult Copperhead feeds on a range of small mammals, for instance, mice, rodents. Occasionally, they eat lizards, small birds, insects as well as amphibians. They have coexisted with man due to their ability to escape predation by remaining motionless. The snake is native to America (Herrmann par. 3).

American Bullfrog (Rana catesbeiana)

According to Stebbins (32), Bullfrog is the largest true frog being 9 to 20.3 cm in length. Its color ranges from yellow to green with some dark grey mottles. The frog has a large external eardrum having the hind legs webbed apart from the last joint made up of loner toe. The amphibian has no dorsolateral ridges. The bellys color ranges from cream to white, and sometimes, it has grey mottles. The species is not native to all the parts of the USA with the exception of central and eastern parts of the country. The range of its habitat is typically eastern and central U.S, New Brunswick as well as Nova Scotia. They inhabit aquatic environment which includes ponds, low moving streams and lakes.

In terms of diet, it is interesting that they are capable of eating any food that they will be able to swallow. Their diet is made up of fish, mammals, frogs, insects as well as birds. Their hatchlings eat algae, invertebrates as well as plants. The introduced species is responsible for the decline of a number of native fauna (Day, Klingler & Bloomberg 83). The individuals of this species have gained a competitive advantage over the natives because the first grow and develop in an environment where competition is fierce, thus their prey is deemed to be captured.

Reproduction takes place between May and August and March and October. Fertilization is external. Bull frogs attain sexual maturation between one and three years of age. After tagging a territory, a male makes a call at night to attract a female. The choice is made when a female enters the territory. Eggs, about 20,000, are laid initially floating the sink under aquatic vegetation (Stebbins 34). The tadpoles are between 10 and 17 cm in length taking 2 years to transform. It has been established that when in their natural habitats, these amphibia can live a maximum age, from eight to ten years. However, when in captivity, they live longer usually reaching sixteen years (Alexander, Zim & Arnold 163).

Works Cited

Clapham, Richard. Foxes, Foxhounds and Fox-Hunting. Memphis, Tennessee: General Books LLC, 2010. Print.

Day, Leslie, Klingler, Mark A. and Bloomberg, Michael. Field Guide to the Natural World of New York City. New York: Johns Hopkins University Press, 2007. Print.

Ehrlich, Paul R., Dobkin, David S. and Wheye, Darryl. The Birders Handbook: A Field Guide to the Natural History of North American Birds: Including All Species That Regularly Breed North of Mexico. New York: Fireside, Simon & Shcuster Inc., 1998. Print.

Ferguson-Lees, James and David A. Christie. Raptors of the World. London: Christopher Helm, 2001. Print.

Gertsch, Willis John. American Spiders. Memphis, Tennessee: General Books LLC, 2010. Print.

Herrmann, Bree. Agkistrodon contortrix. Animal Diversity Web. University of Michigan Museum of Zoology. 2000. Web.

Levi, Herbert W., Levi, Lorna Rose and Herbert Spencer Zim. Spiders and Their Kin: A Golden Guide. New York: St. Martins Press, 2001. Print.

Martin, Alexander C., Zim, Herbert S. and Arnold L. Nelson. American Wildlife & Plants: A Guide to Wildlife Food Habits. Toronto, Ontario: Dover Books, 1951. Print.

Northern copperhead (Agkistrodon contortrix mokasen). Virginia.gov. Virginia Department of Game and Inland Fisheries. 2011. Web.

Rue, Leonard Lee. Complete Guide to Game Animals: A Field Book of North American Species. USA: Grolier Book Clubs, Inc., 1981. Print.

Stebbins, Robert. A Field Guide to Western Reptiles and Amphibians. New York: Houghton Mifflin Company, 2003. Print.

Wright, Anna. Handbook of Frogs and Toads of the United States and Canada. New York: Cornell University Press, 1949. Print.

According to Robert M. Sapolsky, human beings feel that they are unique, unlike other species. This has been questioned by studies that have been done on other primates. Theodosius Dobzhansky, an evolutionary biologist, viewed that all species are unique. According to him, humans are unique; thus, they feel more proud of their specialty.

Robert Sapolskys human nature focuses on neurobiology and primatology. In his perspective, he looks at what makes humans more violent, has empathy, personality, and be creative. Other species are capable of using symbols in reference to objects and actions. They can also make inventions on how to use tools. Even other primates have a theory of mind in which they are capable of recognizing differences in individual thoughts and knowledge.

Sapolsky challenges human uniqueness in terms of human social life. Some primates are asocial, it is difficult to understand primate living in isolation. To him, humans have a rich social life. It had been taken that humans were the only primates that are capable of killing another human. But other studies have shown that even other primates have the capabilities of engaging in organized violence.

Sapolsky looks at the foolishness of nature versus nurture debate. Animal behavior- from obsessive-compulsive disorder to sexual orientation is not dictated solely by our genes or by our upbringing. No biology. No environment, just the interaction between the two( Robinson nature of the beast).

Sapolsky studied the behavior of baboons to explain the evolution that humanity has undergone. According to him, it is not natural for humans to have prolonged stress. Humans should try to get rid of stress by changing the way in which they live, just like other primates are adapted to physical stress on a short term basis.

Sapolsky believes that environmental differences, however small, largely affect human behaviors. Humans, by nature, do not like experiencing new things as they get older. In his essay on Genetic hyping, genes, of course, have plenty to do with behavior.

Genes determine your intelligence, and your personality, and certain genetic profile cause criminality, alcoholism& Genes influence behavior, environment influence behavior, and genes and environment interact.

Sigmund Freuds philosophies differ from Robert Sapolskys views on human nature.

According to Sigmund Freud, the father of psychoanalysis, actions of the gene in humans are intertwined completely with the environment. What should be taken into consideration is what these genes do to the environment. We should not predict behaviors by looking at only one fact.

Sapolsky shows that primates were, in a way, independent from natural factors. This is called cross-fostering. He developed theories on the organization of the human mind. Human behaviors relate to the environment in a conscious or unconscious form. Various systems in body control behavior in animals. Behavior becomes complex due to the high capacity of the system in response to adjusting new behavior.

Robert Sapolskys analysis and studies of primates have expanded in the variations of social practices to explain the natural history of peace. Some primates have been dominated by violence, while others are characterized by egalitarianism, cooperation where various patterns have emerged.

Some species are less aggressive than the others, for example, gibbons or marmosets live in a group in rain forests where they get plenty of food. These animals have the same size, males and females where they mate and reproduce for life. This doesnt exist in violent species, for example, the bamboo and the rhesus monkey. (Sapolsky 1-8)

Robert Ardrey has popularized the theory of human  as  killer  apes where humans have high chances of attaining peace. Primates species can be peaceful or violent as social structures and ecological surroundings can drive their behaviors. Sapolsky view that some of the species, despite their violent characteristics, are capable of making peace.

Primates species are capable of reconciling after being involved in the fight. For example, it was observed by Frans de Waal in the 1980s that about 27 primates of different species were cooperating, thus reducing further aggressive. Reconciliation is also observed in violent primates, and it comes after violence and conflict.

According to biological anthropologists, human behavior requires a strong, established tradition, as, throughout human history, humans had lived by cooperating as found in hunters-gatherers societies.

The world today is full of conflicts and wars among nations, states, and societies. The world today is seeking on the way how to achieve peace globally to face these challenges.

Robert Sapolskys views on natural peace can be relevant today in addressing this crisis. His ideas have been applied in the global war against terrorists, in various theories. The just war theory has been understood in representing a middle way between real politicking and focus on self-interest. However, they are those who hold that achieving world peace cannot be achieved.

According to Robert Sapolsky, primates, especially humans, are capable of abandoning any aggressiveness if there exists no interest in the pursuance of the aggression. War is inevitable if the cost of making it exceeds its benefit. Many believe that war cannot end until humanity ends. Some scholars traced back warfare in history when humans shared with primates like Chimpanzee.

In this era, chimpanzees mostly male of a similar troop were raiding their neighbors and killing them. (Sapolsky 6) Chimpanzees like violence, and this paved the way for human war. Wrangham, like Sigmund Freud, had linked male aggression to sex drive.

Many scholars believe that if war is inevitable, peace cannot be realized due to factors like an ecological crisis, social unrest, violence, overpopulation. Warfare is endemic to many societies; the primitive hunters gather in industrialized areas, which causes some tension among their population.

Works Cited

Sapolsky, Robert M. A natural history of peace. New York. 2006.

Sapolsky, Robert M. Biology and Human Behaviour: The Neurological Origin of Individuality,2^nd edition. New York. 2005.

Robinson, Mark. The nature of the Beast. Stanford magazine Book and authors. 1997.