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Inside the human cell are tiny structures called organelles; these organelles have various functions that are vital to cell life. Each organelle plays a role in keeping the cell moving along, and when these organelles are damaged they can negatively affect a myriad of body functions. One of the most important organelles is the mitochondria; the power house of the cell. A mitochondrion creates ATP which is the cells form of energy. The mitochondria have a distinct structure with a smooth outer membrane, and inner membrane and an inner matrix. The matrix is the soft substance in the middle of the mitochondria, and is accompanied by the folding cristae of the inner membrane. The cristae folds of the inner membrane are important as they create more surface area for reactions to synthesize in the cell; this makes the shape of the mitochondria optimal for performing its function. Inside the matrix and cristae are enzymes that break down food glucose to fuel the cell. This is why the mitochondria is considered the powerhouse of the cell as it is the main source of energy for the cell to function. The amount of mitochondria per cell varies as some cell types need more energy than others. For example, the mitochondria are abundant in muscle cells because the muscles require a ton of energy to move around. Overall, while the mitochondria plays an extremely important role in the cell, it is important to remember that all the other structures of the cell play a specific function as well. All the organelles in a cell work together and are equally as important to cellular health. 

The most important component of neuron transmission is probably the neuron itself. A neuron is made up of several parts, the dendrites (which receive information in the form of chemicals), the cell body, the axon, and the axon terminals (where a signal is sent out to other neurons). These parts of the cell work together to receive and transmit different types of signals. This transmission is possible through graded potentials and action potentials. Graded potentials can be either excitatory or inhibitory, based on the signals strength. If a signal is strong enough, it gets transmitted as an action potential. 

The simple pendulum experiment measured the amount of time ten periods of rotation took place when varying angles of displacement.  Each angle was increased by twenty-five degrees the rotation responded by increasing the amount of time ten rotations took place with an average of 7.6 seconds/10 rotation. Though only the first two rotations were observed to be gradually increasing the last two measured angles increased by more than three seconds. The big difference in time is troubling because each increase should have been less than a second. In my observations, I thought that the increase of angle affected the amount of air friction the pendulum went against. The experiment was interesting because it made me think what if a wrecking ball was used to crash a building the wrecking ball would have to be angled at a smaller degree to cause less disturbance when there is only one target.

                There a numerous methods of reproduction. For instance, many organisms reproduce through a method known as ovipary. This simply means that the organism lays their eggs. The eggs may be fertilized before or after laying. A secondy method is known is vivipary. In organisms that reproduce by vivipary, they will hold their eggs until hatching. Vivipary comes in two forms, Lecithotropy and Matrotrophy, which is defined by the method of nutrients given to the embryo. During Lecithotrophy, the embryo is sustained by lecithin found in the yolk of the egg. Matrotrophy adds additional methods of sustaining the embryo. These methods include: Oophagy, Adelphophagy, Placentation, Epithliotrophy, and Dermatotrophy. During Oophagy, the mother will produce additional eggs, which may or may not be fertilized, which the current embryo will feed on. Adelphophagy is very similar in that an embryo will feed on other embryos within the mother. Placentation simply connects the embryo to the mother’s circulatory system, allowing it to gain nutrients from the mother more directly. During Epithliotrophy, the mother produces a lining within her womb, which the embryo may ingest for further nutrients. This too is similar to Dermatotrophy, in which the embryo will ingest parts of the mother’s outer skin for nutrients. These methods will allow for an offspring to be larger and thus more viable, however it requires a substantial energy sacrifice for the mother.

In this day and age, we have access to an endless amount of information at our fingertips. While the Internet has a large amount of resources available for us to see, not everything we read online is trustworthy. In class today, we looked at a variety of different websites and determined whether or not they were reliable sources. My group was given a link to the Sierra Club Home Page, which is a non profit organization. Many of the articles or posts on the website did not have clear resources or references cited. Additionally, the appearance of the website was disorganized and had a lot of advertisements. The website appears to be very political and it seems like the creators are aiming to have as many people join and spread their movement. While the organization seemed to be supportive of the outdoors as well as science, the articles were clearly biased and did not have a reliable authors. Another group showed us the website for the Science Journal, which seemed much more trustworthy. The articles on Science had peer-reviewed articles and had references cited throughout the website. It is always important to examine sources on the website before using them to find facts because anyone can create a website and post things for the whole world to see.

Animals communicate within their species via four major modalities. The first of which is auditory signals. These are the calls, whines, and noises that each animal makes to communicate. Each noise has its own meaning behind it and context is extremely important for such situations. For example, during mating season, black-back gulls make a “mew” sound which is a sign of hunger and the desire to nuptial feed. This same sound is made by the gulls outside of mating season in order to call in back up for territorial disputes. Visual cues such as body position, colorations, and even dance or other ritualistic movements are the next modality of communication. These visual cues can be used as signs of aggression, dominance, and of course fertility. The third modality is the animal’s chemical signals. As we all know, each organism has a set of pheromones which elicit a response in a partner. This chemical signal is used to signify the beginning of mating season and the organism’s ability to mate. Lastly are tactile signals. Organisms may touch, poke or prod at each other to send a signal. An example of this once again comes from the black back gulls whose females often rub their heads on a mate’s neck to beg for food and/or sex. Each modality has unique characteristics, and all send different signals to members of the species. Therefore, it is important to analyze the situation to try and decipher the message being broadcasted.

           Animals communicate through four major modalities. The first is via auditory signals. These are the calls, whines, and noises that each animal makes in order to communicate. Each noise has its own meaning behind it and context is extremely important. For example, during mating season, black-back gulls make a mew sound which is a sign of hunger and the desire to nuptually feed. This same sound is made outside of mating season in order to call in back up for territorial disputes. Another modality would be visual cues such as body position, colorations, and even dance or other ritualistic movements which can indicate a number of things as well. The third modality is the animals chemical signals. As we all know, each organism has a set of pheremones which elicit a response in a partner. This chemical signal is used to signify the beginning of mating season and the organisms ability to mate. Lastly are tactile signals. Organisms may touch or poke or pro at each other in order to send a signal. An example of this once again comes from the black back gulls who's females often rub their heads on a mates neck to beg for food and/or sex. Each modality has unique characteristics and all send different signals to members of the species. Therefore, it is important to analyze the situation in order to try and decipher the message being broadcasted.

In comparing the hilly area to the flat area, the results portrayed that the hypothesis that there would be less diversity on a hilly area compared to a flat area because it would be very hard for the plants to absorb the nutrients was correct. Though it seems as if a hill would help to spread nutrients over a broader area of plants, the water would run down too quickly resulting in only a minimal amount of nutrients able to be absorbed. However, the nutrients would most likely be too little of an amount to fully saturate the roots of the plants. However, on a flat area, the nutrients can fully sink into the ground, providing much more room for diversity. In Table 2 of the hilly area, the data showed that species 6 dominated the area. From this, it can be assumed that this species is more suited for survival on a sloped area than most species of plants. This may be due to the plant having shorter roots or the plant being more self-sufficient and only requiring a small amount of nutrients to survive. It can further be presumed that on hilly areas specific types of plants will be found.

Birdsong is used to communicate with other birds, similar to the way humans communicate. Birdsong is taught the same way humans learn language: they learn from their parents and it is passed down. In addition, there are different dialects for different regions. Also, children birds and humans both hear their mistakes as their learn their languages. Depending on the environment in which a bird lives, the pitch and type of song the bird sings may be different. A bird’s song is meant to be heard for as far as possible so the recipient can hear it clearly. As a result, some birds may have high pitched songs while others may have low pitched songs, depending on their environment and who they are trying to communicate with. For example, deserts are much more open than forests, so birds in the desert usually use “the buzz” while birds in the forest may use low pitched songs so it won’t be lost amongst the trees and ground. Males try to show off their skill and compete for mates through their songs. Males will usually create much more complex songs in hopes of impressing a female and making them their mate.

It is often wondered how visual and sensory stimuli affect a child’s development. While ‘nature versus nurture’ is an extensive and prolonged debate, it is a relevant topic when trying to understand child development and growth. In a recent experiment, rats were split up and placed into three scenario cages: a cage with adequate resources and space, a cage without adequate resources and space, and a cage with an excessive amount of resources and space. After weeks of living in these the scenarios, the scientists collected the rats and measured each rat’s brain radius and brain activity. As a result, the rats living in the cage with excessive amounts of resources and space had a very different brain chemical make-up and size then the rats living under impoverish circumstances. More specifically, the cerebral cortex of the brains in the rats living in great conditions were larger and more developed; this indicates that brain development is dependent on outside experience or ‘nurturing’ factors.  This is significant in proving that brain development is affected by living experiences; and now the nurture side of the ‘nature versus nurture’ debate has a solid piece of evidence to back it up.