Water and Gas Flow Measurements

The objective of this experiment was to test the effect of a specialized type of diffusion called osmosis, “which involves in selective transport of water molecules across a selectively permeable membrane” (Lab Manual 2nd edition). It was hypothesized that osmosis will occur when there is an uneven distribution of solute in a solvent. The more abundant the solute is in solvent, the higher the rate of osmosis through the diffusion gradient forming a hypertonic or hypotonic solution. Solvent with equal or no solute forms an isotonic solution. Throughout this lab, data was collected and compiled to analyze these effects across selectively permeable membranes. The results indicated that the water molecules indeed move from

The human body is made up of numerous cells that undergo various internal processes. These processes play a critical role in maintain the body in its perfect wellness and health. Some of these processes are basic as they involve the simplest molecules they enhance body development by creating and repairing body tissues and organs. Simple diffusion, facilitated diffusion, active transport, osmosis, and filtration are key processes that enhance body performance.

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.

The use of nano-materials and extreme precision micro-engineering has the potential for great improvement in the world of electronics and information technology by providing smaller, faster, and more powerful computers and this has been at the forefront of the nanotechnology commercialization . Great examples of how nanotechnology is currently being used in these fields are products such as processors, data storage, and memory components made with nano-materials, TVs, monitors and even smartphone screens that use organic light-emitting diodes (OLED), and waterproof electronics such as smartphones due to the application of nano-coatings

The purpose of this experiment is to observe the natural process of osmosis using drops of sheep’s blood in various saline solutions. Since the cell membrane is a selective membrane, the water goes in and out freely but a solute such as NaCl it cannot freely move in or out. Osmosis is a passive process that doesn’t require the input of energy to transport water molecules across a membrane. The channels that allow water to enter or leave a cell are known as aquaporin. Using aquaporin, water moves from a solution with a low solute concentration to a solution with a higher solute concentration. This process continues until equilibrium in solute concentration is established between a cell and its environment.

Every cell membrane incorporates a fluid mosaic model. The “mosaic” of protein molecules embedded in a lipid bilayer. It’s fluid as most proteins and lipid molecules drift through it. The membrane consists of a phospholipid bilayer embedded with various proteins. The proteins help to get polar/hydrophilic molecules through the plasma membrane. Polar molecules have difficulty passing thru the hydrophilic membrane. Nonpolar molecules however, easily pass thru. The proteins can be integral proteins, meaning they go all the way through the lipid bilayer or peripheral proteins that sit on the hydrophilic outer layer and wait for something to happen. The layers are somewhat fluid, allowing the proteins to move across them. See diagram below.

During one open-close cycle, ATP binds to the first site NBD1 and is hydrolyzed, this release of energy opens the MSDs pore, allowing active transport of the chloride ion through the cell membrane. Then a second ATP is bound NBD2 and hydrolyzed charging the closure of the channel (Gadsby & Nairn, 1999). Lastly, at the R-domain, the phosphatases protein returns the channel to its inactive state (Sheppard & Welsh, 1999).

1. Osmosis, Active transport, and Facilitated diffusion Osmosis: Osmosis is the facilitated diffusion of water across the cell membrane of a cell. The inside layer of the cell membrane is hydrophilic, meaning water cannot easily pass through the membrane. The cell membrane has to have aquaporins, which are water channel proteins, that move the water across the membrane. If there is a water and salt solution outside the cell, the salt can enter the cell by diffusion, but the cell membrane is not permeable to the water.

Effective transport systems in multicellular plants and animals, although with apparent differences, have similarities as they all possess a system of vessels in which substances are transported, a driving mechanism to ensure that substances move in the correct direction and importantly, a suitable transport medium.

Water flows from high water potential to low water potential. They have three routes for that: the transmembrane route (out of one cell, across a cell wall and into another cell), the symplastic route (via the continuum of cytosol) and the apoplastic route (via cell walls and extracellular spaces). Roots are another way for water uptake and transport (example: mycorrhizae and endodermis). This transport is regulated by the compartmental structure of plants. The concept of transpiration is made possible through adhesion and cohesion.

Aquaporin consists of a tetramer (Verkman et al, 2014) and each monomer has a single aqueous pore that allows water transportation and prevents proton transfer (Agre et al, 2002). There is an extracellular and cytoplasmic vestibule in each monomer which connects to a central amphipatic pore region that has a hydrophilic (α-carbonyl groups) and hydrophobic surface that helps preventing permeation of larger molecules (Verkman et at, 2014). There are six membrane domains in each aquaporin that then form

In this lab report an experiment will be conducted over the matter of how cell membrane transport is utilized by the cell. The experiment is going to give insight of how osmosis is prevalent in the process of cell membrane transport, osmosis can be defined as the diffusion of water through a semipermeable membrane. Diffusion can be misinterpreted for osmosis at times but the difference between them is that diffusion “equally distributes molecules throughout the environment”. The membrane in the lab will be represented by the membrane of potato slices; the potato slices will be incubate in a isotonic solution, hypotonic solution, and a hypertonic solution. An isotonic solution is when “two solutions have the same osmotic pressure across a semipermeable

Background Information: All cells have membranes that are semi-permeable, meaning that they allow certain substances to enter while others are not allowed into the interior of the cell. This process by which water crosses cell membranes from regions of low solute concentration to regions of high solute concentration to attain equilibrium on either side is called Osmosis. Cell membranes can only be completely understood by studying living membranes to demonstrate its properties involving passive transport, for example, osmosis (Chung et al.,2013). The primary factors which determine the permeability of a living organism’s membrane is the concentration gradient and the size of the molecule compared to the size of the membrane’s pores.

The cellular environment is aqueous, meaning that the solutes dissolve in water (solvent). Water may cross voluntarily through the membrane by osmosis. Most ions move through protein channels, while transport proteins import larger molecules like carbohydrates.