cells require a layer to separate the inside of the cell from the outside world. Cells have a semi-permiable membrane which controls what can and cannot enter the cell. In animal cells, as well as some others, this membrane is all that separates the cell from its surroundings. Plant cells, and many single-celled organisms such as bacteria have a rigid cell wall beyond the membrane that provides structure. (Buck) Cell membranes act as the cell's gatekeeper, but are not especially rigid or strong. Cell walls can limit the entry of certain types of molecules, but they do not provide the fine-grained traffic control function of the membrane. Cell walls, however are rigid and strong.
Cell membranes are semi-permeable; they only allow certain molecules to enter and exit. Some molecules, such as water can pass through the membrane through osmosis or diffusion. This process does not require any energy to be….

Chemical Principles
Life is so varied and unwieldy, it possibly will surprise some to learn that it can actually be broken it down into four basic groups of molecules. The four basic categories of molecules for building life are carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates serve numerous purposes, which goes from energy to the structure and passes on to chemical communication, as polymers or monomers. Many have encountered carbohydrates once or twice. Experts refer to them nonchalantly as "sugars," particles made of carbon, oxygen and hydrogen. A sugar molecule also has a carbon backbone, typically five or six carbons. The sugar molecules are able to link together in chains or in pairs or branching "trees," either for energy or structure storage.

Lipids, which are hydrophobic, likewise have unlike reasons, in addition to energy storage, structure and signaling. Starch formulates for good, available fuel, something that we directly criticize chemically and disintegrate for….

Cell Division
All living things are complex organisms that are made up of cells. Some are made up of a single cell while others comprise of numerous cells working together. Cells are the basic functional and structural units of living organisms and are known to be the building blocks of life. In humans it is from a group of cells that tissues are made and from tissues that organs are made which enable beings to live.

Cells obtain food and oxygen through their membranes and each membrane has a specific area which can serve contents of only a given volume. Any increase in volume of the cell requires that the area of the membrane increases. Basically, when cells grow the membrane becomes insufficient in aiding the movement of substances in and out and thus to maintain a favourable surface area to volume ratio, cell division must take place. Furthermore, cell division ensures….

Only if the cell can take in nourishment and excrete waste can the other components of the cell like the mitochondria engage in their essential tasks. hen a cell can take in nourishment and excrete wastes, this is the surest first sign of independent life
The problem is that the Cell-u-life Corporation wants an artificial cell that can do more than nourish itself. It wants a cell that can take the place of living stem cells and reproduce, and it is not certain of aerogels can do this. Thus another possibility is trying to create lipid-like structures to make cell membranes in the lab from fat cells in the body that do not come from human sources such as embryos but can reproduce like fat cells.

orks Cited

Team receives grant to study artificial cell membranes."(24 Aug 2005). Stanford News:

Press Release. Retrieved 3 Jun 2007 at h ttp://news-service.stanford.edu/news/2005/august24/aerogel-082405.html.

With our progressing knowledge in molecular biology and the increasing understanding of the various signaling pathways there is no question of doubt that in the near future the prognosis for OSCC would be considerably improved. As with any other disease, prevention is better than cure. Avoiding the well-known risk factors, a well-balanced nutritional plan and regular dental health checkups are the most effective means of preventing Oral cancers.
ibliography

1) Michael King, Kourt Chatelain & Dustin Farris et.al, 'Oral Squamous Cell Carcinoma proliferative Phenotype is modulated by Proanthocyanidins: a potential prevention and treatment alternative for Oral Cancer', MC Complementary and Alternative Medicine, 2007, 7:22, 19 June 2007 http://www.biomedcentral.com/1472-6882/7/22

2) M. Chidzonga, L. Mahomva, 'Squamous cell carcinoma of the oral cavity, maxillary antrum and lip in a Zimbabwean population: A descriptive epidemiological study, Oral Oncology, 2006, Volume 42, Issue 2, Pages 184-189

3) National Cancer Institute, 'Oral Cavity', Accessed Jan 15th 2010, available online….

Cell is important because it is the building block of the body. It is a replicating organism that has proteins and cytoplasm and nucleic acids inside a membrane Alberts (2002). Cells are in everything from humans to plants, though each representation of life has its own particular cells. Cells are very small and impossible to see with a microscopic lens. That is why the cell was not actually noticed until such technology came along in the 17th century. Indeed, the name cell, which means small room in Latin, comes from the discoverer of the cell, who thought they looked like the small rooms that monks in the medieval era used to live in, which were called cells (Karp, 2009). Essentially, all living organisms are made up of cells and if there were no cells there would be no life. So the cell is very important.
What do cells do? That depends….

Eukaryotic Cell vs. Prokaryotic Cell:
There are two types of cells found, that originate from a common ancestor - The prokaryotes and eukaryotes. While Prokaryotes are organisms without a cell nucleus and other membrane-bound organelles and are mostly unicellular, but some exceptions are found. In contrast Eukaryotes have their cells have complex structures by internal membranes and a cytoskeleton. The principal membrane bound structure is the nucleus. All animals, plants, fungi, and protists are eukaryotes. (Diffen, 2013) Prokaryotes were the only form of life on Earth until the more complex eukaryotes evolved from them.

Differences between eukaryotic and prokaryotic cells:

The distinctions between these two types of cells create the differences in organisms Thus the groups of organisms that belong basically to the prokaryotes are non-membranous and in contrast the eukaryotes contain membrane-bound organelles, such as the nucleus, while prokaryotic cells do not. Though this is the basic difference, the presence of mitochondria,….

Prokaryotic & Eukaryotic Cells
Cells can be divided into two categories: prokaryotic and eukaryotic cells. Prokaryotic cells are significantly smaller than eukaryotic cells. This size difference is due to the many contents inside a eukaryotic cell that prokaryotic cells do not have. To begin with, prokaryotic cells are always going to be unicellular, while eukaryotic cells can also be unicellular but are many times multicellular (Murray & Baron, 2007). Prokaryotic cells do not have any membrane-bound organelles inside them, such as the nucleus, mitochondria, or lysosome as eukaryotic cells do. The DNA of eukaryotic cells is linear and is contained within the nucleus, while DNA in prokaryotic cells is circular and is contained within the nuclear body, a non-membrane surrounded structure (Murray & Baron, 2007). The number of ribosomes inside a prokaryotic cell is a lot less than those contained in a eukaryotic cell. Prokaryotic ribosomes are about 70s while eukaryotic….

Different Fuel Cell Technologies

U.S Department of Energy (2010) provides the description of different fuel cell technologies. The fuel cell technologies are differentiated according to their efficiency, operating temperatures, costs and application. The classifications are based on 6 major groups:

Alkaline fuel cell (AFC),

Phosphoric acid fuel cell (PAFC),

Solid oxide fuel cell (SOFC),

Molten carbonate fuel cell (MCFC),

Proton exchange membrane fuel cell (PEMFC);

Direct methanol fuel cell (DMFC).

Alkaline fuel cell (AFC)

The AFC generates electrical power using alkaline electrolyte KOH (potassium hydroxide) in water-based solution. The presence of hydroxyl ions within the electrolyte allows a circuit to extract electric energy. The illustration in Fig 2 reveals an alkaline fuel cell. As being revealed in Fig 2, two hydrogen gas molecules combines with 4 hydroxyl ions have a negative charge to release 4 electrons and 4 water molecules. The equation 4 reveals the reaction of oxidation that takes place. (Mark, 2003).

Equation (4)

(Oxidation) 2H2 + 4OH H2O +….

Intrinsically Photosensitive etinal Ganglion Cell
ecent studies on biological anatomy of the eye discovered an additional photoreceptor within the mammalian eye. The cells discovered mediate the primary non-image visual activities with the vision system. The functioning of these cells aids in various significant processes including the regulation of the papillary reflex activity in response to light, as well as, the circadian photo entrainment. These cells, called the intrinsically photosensitive retinal ganglion cells respond to more than the absolute light. The ipGCs have a unique feature of activity, as they differ from the usual photoreceptor cells of cones and rods. The rods and cones mediate on the vision of images by signaling the contrasts in light after adaptation. Interestingly, the ipGCs also do adapt to light contrast. The cells show sensitivity to flash of light, as is the case with other photoreceptors. The factor of action of the intrinsically photosensitive ganglion cells….

On average, male skeletons are larger than female skeletons, but just as some women are larger than some males, this distinction does not hold firm in all instances. Female pelvic regions tend to be wider than male pelvic regions, an evolutionary feature that has made childbirth easier. Female bones tend to be thinner and less dense than male bones, and thus the female skeleton tends to be lighter than male skeletons.
The skull is one of the most notable sites of difference between male and female skeletons. The teeth of males tend to be larger, and above their eye sockets men tend to have a more visible brow ridge while women often have none. The male skull tends to have a squarer (as opposed to a pointed) chin and is more angular in its demarcations than the female skull. Women's nose openings are more apt to be pointed, rather than….

Fuel Cells in Green Engineering
The energy tomorrow is beginning to be available today. Fuel cells, which just a very few years ago were a pipe dream, are becoming g a reality, and they are used in areas ranging from space exploration to toy motivation (Joy). The promise of the fuel cell can be seen in the fact that they use the most abundant source of energy on the planet, Hydrogen atoms (Birch). They are also being seen as the energy savior because they emit a common, non-toxic waste which can also be utilized as a saving grace around the globe, water (Joy; Patturaja). A fuel that uses the most abundant element on the planet and emits clean, pure water does seem like science fiction, but there are already being used with it as a motive force.

The space shuttle has always been powered by hydrogen fuel cells (Joy). Although they are….

Fuel Cell Technology
There are over 600 million motor vehicles in the world today. If present trends continue, the number of cars on Earth will double in the next 30 years." ("Cars Emit")

As the demand for energy increase and resources, such as fossil fuel, decrease alternative must be sought. Of these alternatives, hydrogen fuel cell technology, in automotive applications, has significant benefits and is now technologically feasible. Given this knowledge, it is imperative that we begin to set up the infrastructure necessary to utilize this technology.

I have studied this topic over the last three years, and the advancement of the technology has become increasingly exciting. hat was once a dream is now a reality.

I'm going to provide you first with an overview of how fuel cells work and then describe for you the benefits of the use of fuel cells, including why hydrogen is the best choice. And, in the….

a&P Lab
Design Project -- A&P Lab

Ammonia (NH3) is produced by cells located throughout the body; most of the production occurring in the intestines, liver, and the kidney, where it is used to produce urea. Ammonia is particularly toxic to brain cells, and high levels of blood ammonia can also lead to organ failure. The imaginary organelle referred to as a hydrosome functions in a manner that decreases the blood ammonia levels in people, thereby circumventing the need for medications such as to treatment to prevent hepatic encephalopathy and conditions associated with a failing liver. The hydrosome functions similarly to a primary lysosome, also containing a highly acidic interior with lytic enzymes called hydrolases. However, the waste disposal that the hydrosome conducts serves to convert ammonia to a water-soluble waste that is then excreted by the kidneys.

About this Organelle

I came up with the idea for this organelle because many diseases….

Promotes better plant growth by improving the value of fertilizer. Helps prevent plant burning from over use of fertilizers by trapping and slowly releasing valuable nutrients when and as the plants need them.

Improves the cation exchange capacity of soil resulting in less fertilizer requirements.

Natural zeolites make an excellent soil amendment, and are environmentally friendly for landfill dump sites (with the exception of zeolite that has been used as a molecular sieve or filter medium for the removal of radioactive waste or the removal of heavy chemical toxins deemed hazardous by government regulations.)

educes nutrient and fertilizer loss through heavy rains, leaching and irrigation, resulting in less environmental damage through water runoff.

The water retention capability of zeolites allows less irrigation applications.

Zeolite is used to reduce offensive odors, especially ammonia from sewage, animal manure and waste water situations.

This retained valuable nitrogen improves the quality of the resulting manures and sludges making them worthwhile….