Stress and Cellular Membranes

The Science of Stress is an informative video by National Geographic detailing the body response to stress. Stress is the body’s way of getting itself prepared to face a challenge. It is constant problem that everyone has to deal with. It was originally meant to aid our survival, but over time it has become dangerous and lethal to our well being. National Geographic’s video gives us a scientific view of what goes on in our bodies when experiencing stress and its effects on it.

Phospholipids make up most of the cell membrane, in a phospholipid bilayer. Phospholipid molecules form two layers, with the hydrophilic (water loving) head facing the extracellular fluid and the cytosol (intracellular) fluid, and the hydrophobic (not water loving) tails facing one another. The cell membrane is constructed in such a way that it is semipermeable, and allows oxygen, CO2 and lipid soluble molecules through easily, while other molecules like glucose, amino acids, water, and ions cannot pass through quite as easily. That is the meaning behind the chant “some things can pass, others cannot!”.

The cell membranes are the utmost essential organelle that surrounds all living cells. Its purpose is to control what goes in and out of the cells and is accountable for the various other properties of the cells as well. The nucleus and other organelles also have membranes that are practically indistinguishable. Membranes are organised in a mosaic arrangement, comprised of carbohydrates, proteins and phospholipids. This can be seen in Figure 1. The objective of this indirect examination is to study the causes of various solvents and conducts on live beetroot cells. The reason why beetroot cells have been selected for this experiment is because they have a big membrane-bound central vacuole, as seen in Figure 2. The red colour anthocyanin, which provides the beetroot its bright colour is located in the vacuole. The cell membrane encloses the whole beetroot cell. The anthocyanin cannot leak out if the membranes stay unharmed. The red colour can escape if the membranes are hassled or broken.

Diffusion is defined as the movement of molecules from an area of high concentration to an area of low concentration. The diffusion of water molecules through a semi-permeable(selectively permeable) membrane is osmosis. Semi-permeable means that some molecules can move through the membrane while others can not. Diffusion and Osmosis are passive forms of transport requiring no energy. Active Transport utilizes energy in the form of ATP. Water is a solvent that can dissolve a number of substances more than any other substance. Wherever water goes, through the ground or a body, it takes along valuable molecules. Water’s chemical composition causes it to be attracted to many different molecules and be attracted so strongly it disrupts the forces and dissolves it. Water can pass through the semipermeable membrane without any help but can change the solution, on the other side of the cell membrane, depending on how much it diffuses in and out.

This has been shown by a steady increase in Anthon cyanine leaked out of plant cells as the concentration and temperature increases. The purpose of a cell membrane is to control the transport of substances moving into and out of a cell. The membrane is an extremely thin layer (8 to 10 nanometers (nm)) thick, which is partially permeable. It consists mostly of lipids and proteins.

Hypothesis: To investigate the effect of different concentrations of ethanol on the permeability of beetroot cell membranes.

The cell membrane (Plasma membrane) functions to provide cell support, cell stability and control entry and exit of materials from the cell. This study was conducted to test the effects of environmental conditions such as the on beet root cell membrane (Beta vulgaris). Five trials using varied pH concentrations were tested and absorbance rates were monitored. The experimental results showed that the protein function decreased sequentially when the pH decreased. This allowed the betacyanin dye to leak out which created the color that was needed to determine the intensity and therefore the effect of the circumstances. This supported the hypothesis that the more acidic or basic the environmental condition around the beet cell, the more permeable the, membrane indicated by color intensity. Pigment leakage in the solution was analyzed by using a spectrophotometer.

Osmosis can be defined as the force that drives the movement of water due to differences in solute concentration. The process involves the random movement of molecular water molecules through a semi-permeable membrane from regions of higher concentration to regions of lower concentration until both regions equal out (Ledbetter 2013, Ness 2013). Polar substances such as glucose and salts cannot travel through the cell membrane, which

The purpose of this experiment was to alter the cell membrane of the beets, in a given fashion, so that we can test how much betacyanin was able to cross the cell membrane of the beet through various treatment. In which after we would test the absorbance level of each treatment, run it through excel and observe which treatment was most effective at getting betacyanin through the cell membrane more.

Water diffuses across the membrane from the region of lower solute concentration (higher free water concentration) to that of higher solute concentration (lower free water concentration) until the solute concentrations on both sides of the membrane are equal. The diffusion of free water across a selectively permeable membrane, whether artificial or cellular, is called osmosis. The movement of water across cell membranes and the balance of water between the cell and its environment are crucial to organisms. ("Diffusion And Osmosis - Difference And Comparison | Diffen"). A semi-permeable membrane known as the cell membrane surrounds the living cells of both plants and animals. Both solute concentration and membrane permeability are

Osmosis is the passive movement of water from an area of low solute concentration to an area of high solute concentration, normally across a membrane which prevents the movement of solvent. This is a process by which materials may move into, out of, or within cells. Osmosis doesn’t depend on energy provided by living organisms but is affected by the properties of the cell membrane. The rate of osmosis is dependent on such factors as temperature, pressure, molecular properties such as size and mass, and the concentration gradient. In osmosis, the relationship between a solute’s concentration outside of cell and inside of a cell is described in terms of the tonicity of the solution outside of the cell. A cell is in a hypotonic solution when the solute is more concentrated inside the cell and therefore water moves into the cell. In this solution the cell swells as water enters, this may continue until it ruptures or hemolyzes. In the reverse condition, the cell is in a hypertonic solution

The data collected of % transmittance can then be used as an indication of changes in membrane permeability of

Cells are always in motion, energy of motion known as kinetic energy. This kinetic energy causes the membranes in motion to bump into each other, causing the membranes to move in another direction – a direction from a higher concentration of the solution to a lower one. Membranes moving around leads to diffusion and osmosis. Diffusion is the random movement of molecules from an area of higher concentration to an area of lower concentration, until they are equally distributed (Mader & Windelspecht, 2012, p. 50). Cells have a plasma membrane that separates the internal cell from the exterior environment. The plasma membrane is selectively permeable which allows certain solvents to pass through

Eukaryotic cells respond to cellular stress by controlling the translation, stability and subcellular localization of mRNA (Buchan, Yoon, & Parker, 2011). This occurs through the remodeling of translating mRNAs into non-translating mRNPs which accumulate in cytoplasmic RNA- protein granules, known as P-bodies (mainly contain mRNA decay machinery) and stress granules (mainly contain translation initiation factors). (Buchan, Yoon, & Parker, 2011). Several studies reveal that both granules share specific mRNA and many protein components. Stress granules and P-bodies are likely to interact and exchange mRNP between them. In yeast, stress granules are usually initiated in conjunction with P-bodies, and it is partially overlapping P-bodies

Cells are constantly responding to changes in their environment. These types of environmental changes can result in gene expressions and their interactions. The response a cell takes can vary due to its characteristics. Eukaryotic cells respond differently than that of prokaryotic cells. Cells are constantly undergoing stress reactions. In this study we are going to be focusing on stress induced responses in Human cells. But to help analyze reactions found in human cells, studies on other organisms have been performed on species such as yeast and bacterial species. By looking at a wide array of cell responses, we will be able to better understand that of the human body.