Science Essays

Aim:To investigate the effect of varying the concentration of sucrose solutions and to see if osmosis occurs in potato cells. Research/definition:Osmosis is the diffusion of a solvent through a semi permeable membrane from a region of low solute concentration to a region of high solute concentration. The semi permeable membrane is permeable to the solvent, […]

Describe two Variables that affect the rate of diffusion. The two variables that affect the rate of diffusion are: A. The size of the molecule. The larger molecule will spread more easy than the smaller molecule. B. The nature of plasma membrane. If the membrane is composed of lipid part. . merely lipid soluble molecules […]

All cells require essential materials to ensure their survival. Chemical, physical, and biological processes are used to move these materials inside of cells. Similar processes move waste materials outside of cells. These processes can be passive, occurring as a result of basic physical laws and requiring no outside energy from the cell or they can […]

1) The relationship between the rate of diffusion, volume and surface area is that the surface area of a subject somewhat correlates with the volume of the object. When the surface area and volume are set up as a ratio, this gives a good idea as to how fast the rate of diffusion will be. […]

Osmosis is the net movement of water from a high concentration of water to a low concentration of water down a concentration gradient. This is done to equalise the solute concentrations on the two sides. Therefore, in other words, the movement of water is depended on the concentration of dissolved solute in the water (in […]

The investigation which I am going to be carrying out is to estimate the concentration of the cytoplasm of potato cells. I will do this by investigating using the movement in and out of the potato cells through Osmosis. Osmosis is the process whereby water molecules pass through a semi-permeable membrane from a high concentration […]

The text presents experiments and observations on simple diffusion, dialysis, and facilitated diffusion. It provides the molecular weights of Na+ and Cl- and their ability to pass through membranes with different MWCOs. Certain MWCOs allow for diffusion from the left beaker to the right beaker, while smaller materials do not diffuse. Urea concentration is equally […]

Introduction The fundamental components of all living beings are cells. Cells offer structural support, absorb nutrients, and convert energy. They also possess specific functions and genetic material for replication. Furthermore, cells function as metabolic compartments where a variety of chemical reactions occur. There are two categories of cells: eukaryotic and prokaryotic. Both prokaryotic and eukaryotic […]

Introduction In this experiment I am going to investigate the effect of varying concentration of a differing glucose solution on the amount of osmotic activity, between the solution and a potato tuber of a given size. The purpose of this experiment is to demonstrate how living cells rely on osmosis, the diffusion of water. Osmosis […]

Did water move into the cells or out of the cells while they were surrounded by hypotonic solution? Water moved into all of the cells while they were surrounded by hypotonic solution. In which direction did the water move through the cell membrane when the cells were surrounded by the hypertonic solution? The direction that […]

Abstract The purpose of this experiment was to study the transfer of genetic information on plasmid F’lac by using Escherichia coli. Plasmid transfer was measured by using two different methods. The first one was by using selection and contraselection with three antibiotics: streptomycin(which was replaced by naladixic acid for the second part of the experiment), […]

Analysis & Discussion The primary objective of this investigation was to test ultraviolet radiation as an alternative disinfectant for Acanthamoeba in its more resistant cyst form. A previous study had already shown that multipurpose solutions were ineffective compared to hydrogen peroxide based systems at eliminating Acanthamoeba trophozoite contaminations. 5 This was a follow-up to that […]

The HIV/AIDS Epidemic In South Africa Acquired Immune Deficiency Syndrome (AIDS) caused by the Human Immunodeficiency Virus (HIV) is one of many infectious diseases that plague the world today. According to the 2007 AIDS epidemic update put out by The United Nations Joint Program on HIV/AIDS (UNIADS) there were approximately 2. 1 million AIDS related […]

The Role of Agarase in Agar-Degrading Bacteria Abstract Agar-Degrading (agarolytic) Bacteria is physiological class of bacteria capable of utilising agar as a sole carbon source. This ability is made available by the use of agarases – enzymes which break down agarose into oligosaccharides. This physiological class branches through genii, regardless of Gram Stain status or […]

This will include: the color of the medium immediately surrounding the colonies after addition of iodine on PDA plate, whether bubbles were observed or not in the atlas test, the color of the urea slant, the color of the citrate slant, and whether the rabbit plasma remained liquid or became solid due to clot formation, […]

Hypothesis: If the most effective solution for pathogenic bacteria is household bleach, then the descending order from best to least are household bleach, Penicillin, Monoclinic, Household Disinfectant, Anti- Bacterial Soap, Erythrocyte, Sterile Filter Paper. Materials: The materials used in this lab include a agar, a Petri dish, test tubes containing the pathogenic bacteria: Staphylococcus erasures, […]

Antigen recognition allows the immune system to recognize each antigen with tremendous specificity in order to avoid an immune response to host tissues. One way in which the immune system accomplishes this is through the production of antibodies by the B-cell. Each antibody must be able to bind specifically to one part of an antigen; […]

In 1884, the tetanus toxin was discovered in soil bacteria by Arthur Nicolaier. The disease’s transmission was demonstrated the same year by Antonio Carle and Giorgio Rattone, who induced it in rabbits using pus from a human tetanus case. In 1889, Kitasato Shibasaburo isolated C. tetani from a human victim and proved its ability to […]

Between May to July, Malaysian had been surprised by a ‘new’ communicable disease which carried a weird name, it called ‘Chikungunya’, the term is actually derived from the ‘Makonde’ word meaning “that which bends up” as referred to the stooped posture developed resulting of arthritic symptoms of the disease. It is belief that the chikngunya […]

Yellow fever, caused by different virus families, is a form of hemorrhagic fever. Although some individuals infected with yellow fever may not display any symptoms, others might experience symptoms such as headaches, muscle and body pains, fever, chills, nausea, vomiting, fatigue, and weakness around three days after being infected. Yellow fever, which is primarily found […]

Extensive investigation was carried out on rheumatic fever during the early 1900s due to its high prevalence in children worldwide, leading to numerous hospitalizations. While developed nations have seen a decrease in rheumatic disease prevalence since the late 1900s, non-developed countries still struggle with significant issues related to rheumatic fever, which are now even more […]

Objectives: To measure the different phases of growth of Escherichia coli through absorbance reading and viable count measurements To plot the growth curve of Escherichia coliIn the experiment, the different growth phases were observed through the analysis of the absorbance of broth with inoculated organism (E. coli). There was no viable cell counting done with […]