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Chemistry, surprisingly enough, plays a large role in the study of Biology. That is why Chapters 2 and 3 of our Biology textbook are devoted to a review of the smallest building blocks of our world. Today in class, our minds were refreshed on the basics of chemistry, particularly atoms and how they bond together.

Unlike our unfortunate rivals in Chem II, us Biology kids do not need to memorize all the elements on the Periodic Table. While about 25 elements are essential for life, the majority of life is made up of carbon, hydrogen, oxygen, and nitrogen. Trace amounts of calcium, potassium, sulfur and phosphorous also exist.

These elements, as well as all the others, bond together based on their electrons. The amount of electrons in the valence shell of the atom determines its chemical behavior. Atoms want to either complete a partially filled valence shell of empty a partially filled valence shell, depending on the number of electrons in that shell. When this happens, bonds between atoms result.

There are both weak bonds and strong bonds in the chemical world. Hydrogen bonds, an attraction between positive and negative ends of molecules, is an example of a weak bond. These bonds only occur between Oxygen and Hydrogen, Nitrogen and Hydrogen and Fluorine and Hydrogen.

Hydrogen Bonding Video (user: mtchemers)

Hydrophilic and hydrophobic interactions also occur between water and another element. The final types of weak bonds are Van derWaals forces and ionic bonds, but we did not discuss them any further in our class today.

Covalent bonds are the strongest bonds in chemistry. These bonds result when two atoms share a pair of electrons between them. This results in the formation of a molecule. Multiple covalent bonds, like double or triple bonds also can result, depending on the number of electron pairs being shared. There are both polar and nonpolar covalent bonds which depend whether of not the electron pair (or pairs) are shared equally between the two atoms. If the electronegativity of one atom is significantly larger than the other, a polar bond occurs.

Finally, hydrogen bonding, like discussed earlier, occurs with water molecules as well. The irregularity of the water molecule gives water some of its unique characteristics. That is the subject of our next chapter, and the next blog as well.

Class was very interesting and brought back some feelings of nostalgia for us, if it is possible to have nostalgic feelings about chemistry.

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There are various factors that influence seed germination, some of which include: sunlight, water, natural causes, predators, fertilization, etc. However, the main ones are sunlight, water, and “food”. These produce the whole sprouting case to occur. In order to begin the lab of seed germination, you need to have a factor (variable), predicted effect, and explanation for prediction. From this logic process, your hypothesis is formed.

The whole point of an experiment is designed so that it is controlled. In this case, the designed experiment is to see whether or not “Miracle Gro” speeds up the seed germination process. For an experiment you need your independent and dependent variable, so “Miracle Gro” would be your independent variable and the rate at which the seed will germinate is your dependent variable.

The materials needed are:

• seeds
• 50mL 5% “Miracle Gro”
• 5  plastic bags
• 5  paper towels
• 10mL graduated cylinder

The experiment is started by putting the seeds in a plastic bag, also known as your germination bag; soil will not be used. To make a germination bag, you place 1 folded paper towel in the plastic bag and lay the seeds in a line, so they are exposed for the germination process. Next add 10 mL of solution to the bag, for dilution ask teacher for ratio. To help keep track of each individual germination process, label your bags, for example 1%, 2%, 3%, etc. When completed with all 5 bags, seal tightly with little air as possible and tape them to a door. As days continue, collect your data and record in a data table including your variables. The number of trial completed should be 5.

In conclusion, the rate at which the seed germinated the best tells you what the dilution of “Miracle Gro” should be for the seed to germinate.

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The major themes in biology are science as a process of inquiry, evolution, energy transfer, continuity and change, the relationship of structure to function, regulation, interdependence in nature, and science and technology in society. The hypothesis in all experiments is the process of inquiry. A scientists makes an educated guess at what he think will be the outcome of the experiment. At the end of the experiment, his “inquiry,” or hypothesis is either proven right or wrong. To ensure that the results of all the variables are correct, it is best that the scientist repeats the process. Evolution is the core theme of biology. It states that all life adapted and slowly evolved onto what it is today through the process of natural selection. Basically, there would be no life or purpose to biology without the process of evolution. It explains the unity of life in their biochemistry and physiology because according to the theory, every living thing has a common ancestor. It also explains the differences, because through the process of natural selection, adaptations have allowed animals with advantageous traits to thrive in particular areas. Energy transfer is related to life, because life is an open system that requires constant input of energy, energy to flow through it, and energy to exit. This continually recycles nutrients through the different organisms. The reason for the continuity of life is found in DNA. DNA is the genetic material which carries traits and biological information through generations. Another major theme is the fact that in all levels of biology, form is related to function. Simply put, from the smallest organelles to the largest organisms, everything in biology is put together in a form that allows it to serve a function that helps preserve the life of itself, as well as other living things in its ecosystem. Organisms regulate themselves to maintain homeostasis. Even when they are surrounded by changing conditions, they have positive and negative feedback loops that allow for the proper response. That way body temperature, pain, etc…can be regulated and kept within a good range. The theme of interdependence in biology says that no organism stands alone, it needs other living creatures, or possibly sunlight to survive. All living things on Earth have some sort of a symbiotic relationship. The last theme in biology is how it relates to science, technology and society. There are moral and ethical dilemmas preventing the further expansion of science. In the field of biology, scientists no longer question if certain things such as cloning are possible. They question if they should do it. By studying the themes of biology, a near infinite mass of information can be generalized, so that one person can have an understanding of all of its aspects.

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