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…...
mlaAndreas, Lpp. "Cell Biology." WikiBooks. February, 2005. http://en.wikibooks.org/wiki/Cell_biology
Buck, Jim. "Cell Wall." Wikipedia. July, 2005. http://en.wikipedia.org/wiki/Cell_wall
Wolf, Jfd. "Cell Membrane." Wikipedia. July, 2005. http://en.wikipedia.org/wiki/Cell_membrane
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…...
mlaReferences
Plumb, Robert C. "Chemical principles exemplified." Journal. Chem. Educ. (2012): 21-24.
Zumdahl, Steven S. Chemical Principles, 7th Edition. Chicago: Cengage Learning; 7th edition, 2013.
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…...
mlaReferences
Bolsover, S., E. Shephard, H. White, and J. Hyams. Cell Biology: A Short Course. 3. Wiley-
Blackwell, 2011. 432.
Conger, Krista. "Scientists turn skin cells into neural precursors, bypassing stem-cell stage." Stanford School of Medicine. n. page. Print.
Morgan, David. The Cell Cycle: Principles of Control. New Science Press, 2007.
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...
mlaWorks 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…...
mlaBibliography
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', BMC 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 at, http://oralcancerfoundation.org/dental/pdf/oral_cavity.pdf
4) Keyvan Nouri, 'Skin Cancer: Oral Cancer', McGraw-Hill Professional, 2007
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…...
mlaReferences
Alberts, B. (2002). Molecular Biology of the Cell. UK: Taylor and Francis.
Karp, G. (2009). Cell and Molecular Biology. UK: Wiley and Sons.
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,…...
mlaReferences
Cooper, GM. (2000) "The Cell: A Molecular Approach." Sunderland (MA): Sinauer
Associates.
Diffen. (2013) "Eukaryotic Cell vs. Prokaryotic Cell" Retrieved 18 April, 2013 from http://www.diffen.com/difference/Eukaryotic_Cell_vs_Prokaryotic_Cell
Gregory, Michael. (n. d.) "Protists" Lecture notes. Retrieved 18 April, 2013 from http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio%20102/bio%20102%20lectures/protists/protists.htm
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…...
mlaReferences:
Murray, Patrick R., and Ellen Jo. Baron. Manual of Clinical Microbiology. Vol. 1. Washington, D.C.: ASM, 2007. Print.
Nester, E., Anderson, D., & Roberts, C.E. (2012).Microbiology: A human perspective. (7th ed). New York, New York: McGraw-Hill Higher Education.
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 +…...
mlaReferences
Andujar, J.M, Segura F. (2009). Fuel cells: history and updating. A walk along two centuries.
Renew Sustain Energy Rev. 13:2309 -- 22.
Grove, W.R. (1842). On a Gaseous Voltaic Battery. Philosophical Magazine and Journal of Science .vol. XXI: 417 -- 420.
Kordesch, K.(1999). Alkaline fuel cells applications, innovative energy technology. Austria: Institute of High Voltage Engineering, U Graz.
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…...
mlaReferences
1. Bellintani-guardia, B., & Ott, M. (2002). Displaced retinal ganglion cells project to the accessory optic system in the chameleon (chamaeleo calyptratus). Experimental Brain Research, 145(1), 56-63. doi: http://dx.doi.org/10.1007/s00221-002-1091-z
2. Ben Simon, G.,J., Hovda, D.A., Harris, N.G., Gomez-Pinilla, F., & Goldberg, R.A. (2006). Traumatic brain injury induced neuroprotection of retinal ganglion cells to optic nerve crush. Journal of Neurotrauma, 23(7), 1072-82. doi: http://dx.doi.org/10.1089/neu.2006.23.1072
3. Engelund, A., Fahrenkrug, J., Harrison, A., & Hannibal, J. (2010). Vesicular glutamate transporter 2 (VGLUT2) is co-stored with PACAP in projections from the rat melanopsin-containing retinal ganglion cells. Cell and Tissue Research, 340(2), 243-55. doi: http://dx.doi.org/10.1007/s00441-010-0950-3
4. Henderson, D., & Miller, R.F. (2003). Evidence for low-voltage-activated (LVA) calcium currents in the dendrites of tiger salamander retinal ganglion cells. Visual Neuroscience, 20(2), 141-52. Retrieved from http://search.proquest.com/docview/198275379?accountid=458
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…...
mlaReferences
The cell cycle & mitosis tutorial. (1997). The Biology Project. University of Arizona. Updated 2004. Retrieved February 10, 2010 at http://www.biology.arizona.edu/Cell_bio/tutorials/cell_cycle/cells3.html
Cell division via mitosis. (2010). Ivy Rose UK. Retrieved February 10, 2010 at http://www.ivy-rose.co.uk/HumanBody/Cells/Cell-Division_Mitosis.php
Richards, a. (2002). Male and female skeletons. Retrieved February 10, 2010 at http://transwoman.tripod.com/skeleton.htm
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…...
mlaWorks Cited
Birch, Amanda Sue. "Microbial Fuel Cells: Converting Waste to Water and Watts." Engineering and Technology for a Sustainable World. (2010). Print.
Fields, Scott. "Making the Best of Biomass: Hydrogen for Fuel Cells." Environmental Health Perspectives. (2003). Print.
Joy, Linda E. "A Basic Overview of Fuel Cell Technology." Automotive Community. (2007). Web.
Khan, Abdul Majeed. "Electricity Generation by Microbial Fuel Cells." Advances in Natural and Applied Sciences. (2009). Web.
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…...
mlaWorks Cited
Cars Emit Carbon Dioxide." 1997. Global Warming Focus on the Future. 27 May 2004. http://globalwarming.enviroweb.org/ishappening/sources/sources_co2_facts3.html.
Efficiency of Fuel Cells." 2004. HowStuffWorks.com. 27 May 2004. http://science.howstuffworks.com/fuel-cell4.htm .
Gasoline and Battery Power." 2004. HowStuffWorks.com. 27 May 2004. http://science.howstuffworks.com/fuel-cell5.htm .
Proton Exchange Membrane." 2004. HowStuffWorks.com. 27 May 2004. http://science.howstuffworks.com/fuel-cell2.htm .
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…...
mlaWorks Cited:
Batshaw ML, MacArthur RB, Tuchman M. Alternative pathway therapy for urea cycle disorders: twenty years later. Journal of Pediatrics. 2001; 138: S46-55.
Haberle J, Boddaert N, Burlina A, Chakrapani A, Dixon M, Huemer M, Karall D, Martinelli D, Crespo PS, Santer R, Servais A, Valayannopoulos V, Lindner M, Rubio V, and Dionisi-Vici C. "Suggested guidelines for the diagnosis and management of urea cycle disorders." Orphanet Journal of Rare Diseases 2012: 7, 32. doi:10.1186/1750-1172-7-32. PMC 3488504. PMID 22642880 Retrieved http://www.ojrd.com/content/7/1/32
Interactive Concepts in Biochemistry - Interactive Animations. John Wiley & Sons Publishers, Inc. 2002. Retrieved http://www.wiley.com/legacy/college/boyer/0470003790/animations/cell_structure/cell_structure.htm
Prasad S, Dhiman RK, Duseja A, Chawla YK, Sharma A, Agarwal R. "Lactulose improves cognitive functions and health-related quality of life in patients with cirrhosis who have minimal hepatic encephalopathy." Hepatology 2007: 45 (3): 549 -- 59.
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…...
mlaReferences
Bowman, Robert. "Properties of Zeolites - Robert S. Bowman, New Mexico Tech Earth&
Environmental Science." New Mexico Tech. 2003. New Mexico Tech. 3 May 2005 http://www.ees.nmt.edu/bowman/research/SMZ/ZeoProp.html .
Falconer, John and Richard Noble. "Zeolite Membrane Research." Colorado.edu. Colorado.edu.3
May 2005 http://www.colorado.edu/che/FalcGrp/research/zeolite.html .
Antibacterial Properties of Silver Nanoparticles from Euphorbia: A Literature Review
Silver nanoparticles (AgNPs) have gained significant attention for their potent antibacterial properties. Euphorbia, a diverse genus of flowering plants, has emerged as a promising source for synthesizing AgNPs. This review investigates the antibacterial properties of AgNPs derived from Euphorbia species, summarizing the key findings reported in scientific literature.
1. Synthesis of AgNPs from Euphorbia
AgNPs from Euphorbia are typically synthesized using plant extracts or biological components. The reducing agents present in the extracts, such as flavonoids, terpenoids, and reducing sugars, facilitate the reduction of silver ions to form AgNPs. The particle size, shape,....
1. The Structure and Function of Cell Organelles
2. Cell Division: Mitosis vs. Meiosis
3. The Role of Stem Cells in Regenerative Medicine
4. The Impact of Genetics on Cellular Function
5. The Importance of Cell Communication and Signaling
6. Cellular Respiration: How Cells Produce Energy
7. The Role of Cell Membranes in Maintaining Homeostasis
8. The Connection Between Cancer and Abnormal Cell Growth
9. Cellular Adaptations to Environmental Stress
10. The Evolution of Cells: From Prokaryotes to Eukaryotes.
11. The Role of Epigenetics in Cellular Differentiation and Development
12. Cell Aging: The Effects of Telomeres and Cellular Senescence
13. The Impact of Environmental Toxins on Cell Health and Function
14. The Relationship....
Cellular Structure and Function
1. The Cell Theory: A Cornerstone of Biology
- Trace the history and contributions of cell theory pioneers like Schleiden, Schwann, and Virchow.
- Discuss the key tenets of cell theory and their implications for understanding the structure and function of life.
2. The Diversity of Cell Types: From Prokaryotes to Eukaryotes
- Describe the structural and functional differences between prokaryotic and eukaryotic cells.
- Explore the specialized cell types found in multicellular organisms, including plant and animal cells.
3. Cellular Membranes: Gatekeepers of Life
- Explain the structure and composition of cell membranes.
- Discuss the functions of....
Genomic Insights into Klebsiella pneumoniae Bacteriophages Isolated in Ho Chi Minh City: A Comparative Analysis of the Key Lytic Proteins Holin, Spanin, and Endolysin Introduction
Klebsiella pneumoniae is a Gram-negative, opportunistic pathogen that causes a wide range of infections, including pneumonia, urinary tract infections, and bloodstream infections. The emergence of multidrug-resistant K. pneumoniae strains has become a major concern in healthcare settings, and there is an urgent need for new antimicrobial strategies.
Bacteriophages, or phages, are viruses that infect and kill bacteria. They have been used as therapeutic agents for centuries, and have recently gained renewed interest as a potential weapon against antibiotic-resistant....
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