Energetically Synthesizing Solutes

Halophiles are organisms that not only thrive in environments containing high salt conditions, but also require sodium chloride (NaCl) for growth. Remarkably, halophiles cannot grow on any salt, such as potassium chloride (KCl) or magnesium chloride (MgCl), other than NaCl (Ollivier et. al. 1994). However, the exact salt concentration required by halophiles differ based on different organisms and environments. Consequently, halophiles are further classified based on the optimal NaCl concentration needed for their growth as shown in figure 1. Extreme halophiles require a salt content of 3.4 to 5.1 M (20 to 30%), moderate halophiles require a salt content of 0.8 to 3.4 M (4.7 to 20%) and slight halophiles require a salt content of 0.3 to 0.8 M (1.7 to 4.8%). In order to put these concentrations in perspective, consider the fact that seawater has a salt content of 0.6 M or 3.5% (Larsen 1962). Furthermore, it is essential to distinguish that while halophiles need salt for growth, halotolerant organisms can grow in saline conditions, but do not require salt (Ollivier et. al. 1994).

The answer is B, in the cells of a tide pool animal such as an anemone. This is because tidepool animals are constantly surrounded by water and use osmoregulation to regulate the movement of water in and out of the cell, getting rid of extra water that enters the cells once the inside and outside of the cells are isotonic. The answer could not be A because plants do not osmoregulate due to their desire to constantly be hypotonic and have things coming into the system. It can not be C because red blood cells must reside in an isotonic solution or it will burst and therefore no osmoregulation is needed. Lastly, the answer can not be D because lymphocytes do not osmoregulate

A very carefully regulated process is solute concentration. If there is a sudden increase in water which enters the extracellular fluid, sodium ions will then contribute less to the extracellular solute concentration as the ratio between water and solute has now changed. Osmolality is the amount of solute in a kilogram, hence the osmolality in the extracellular space has also decreased.

In this experiment, we will investigate the effect of solute concentration on osmosis. A semi‐permeable membrane (dialysis tubing) and sucrose will create an osmotic environment similar to that of a cell. Using different concentrations of sucrose (which is unable to cross the membrane) will allow us to examine the net movement of water across the membrane.

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 objective of this experiment is to develop an understanding of the molecular basis of diffusion and osmosis and its physiological importance. Students will analyze how solute size and concentration affect diffusion across semi-permeable membranes and how these processes affect water potential. Students will also calculate water potential of plant cells.

By pumping sodium through the daphnias’ epithelial cytoplasm and passing to the hemolyph, is the organism’s major method for osmoregulation. The process of ion homeostasis ensures the survival of these osmoregulating aquatic organisms. These organisms maintain high body ion concentrations in freshwater and low concentrations in salt water; however, remain restricted to freshwater environments with concentrations lower than 1gL-1 due to the organisms body size determining the sensitivity of freshwater

___The concentration of extracellular K+ ions would be high and this would prevent more K+ ions from diffusing out of the cell.

The effect of pH would cause the growth for three halophiles to increase that its determine from the result when it increase from low pH as it reach at pH 7 and then it cause to decrease. As plasma membrane is been dense to proton that can able to transfer the potassium from its proton. There could be an acid that has strength from its response in which microbes can pump form the proton that some arrange its acid and heat shock proteins that can able to prevent

them from governing the flow of chloride ions and water in and out of cells. Chloride ions help

In Chemiosmosis, protons flow against their gradient from the matrix into the ATP synthase. The

Conversely, animal cells thrive best in an isotonic environment, where there is no net change in their concentration. During the osmosis portion of the lab we created four dialysis bags of varying concentrations and place the bags in solutions of either 30% sucrose or reverse osmosis water (RO water). Two bags held RO water and the two other bags held either a 15% or 30% sucrose solution. We then observed and recorded the mass of the bags over the course of an hour to determine in which direction the osmosis occurred for each bag and at what rate.

Cell membranes are surrounded by a phospholipid bilayer that provides a semipermeable barrier for cells, separating the cytosol from the extracellular environment. Phospholipids are ampithatic, meaning that they have a hydrophilic head and hydrophobic tail, which causes the heads to face outwards towards the water and the tails inwards, creating the bilayer [figure 1]. Small hydrophobic molecules such as O2 and CO2 and small uncharged polar molecules such as H2O and ethanol can diffuse through this bilayer, however larger molecules and ions cannot, and thus require proteins, which are polymers of amino acids joined together by strong peptide bonds. These proteins feature throughout the membrane, and account for around 50% of its mass [http://www.ncbi.nlm.nih.gov/books/NBK9898/] . Not only are proteins required for transport of molecules through the membrane, but they also transport signals and are necessary for the cell support; throughout this essay I will focus on the pivotal role they play with regards to the transport of these molecules and signals, and what occurs when these functions are inhibited.

The pressure changed the most using the 20 MWCO membrane and the least using the 200 MWCO membrane.

Na+ and Cl- are the major ions absorbed by halophytes (Flowers et al., 2010) and they are predominantly what halophytes will use for their osmotic adjustment. It is very important for them to keep the concentration of these ions at an ideal level for the purpose of osmotic adjustment, which is where ion compartmentalisation takes place in the vacuoles (Joshi et al., 2015; Flowers and Colmer, 2008; Flowers et al., 2010). As halophytes have larger vacuoles than glycophytes, they have the ability to store higher concentrations of Na+ and Cl-. As they are able to store these amounts of NaCl there is a need for organic solutes to be created that are compatible with these ions to balance the osmotic potential of mentioned stored ions (Joshi et al., 2014; Flowers and Colmer, 2008). Of course, the levels of ion compartmentalisation vary between species because as mentioned before, there are different levels of