Osmosis

5.4. Electrosensitive hydrogels Hydrogel swells in response to an electrical stimulus with a mechanism very similar to pH, experiences shrinkage, and bending. The major difference between electrical and pH stimulations is that the electric field moves mobile ions in order to regulate an ion concentration gradient through the hydrogel and the solution [54,55]. Polymeric networks containing ionizable groups can have important electrical behavior under an electric field. The electrosensitive…

Surfactant Agents I. Definitions a. Surfactant: A surface-active agent that lowers surface tension i. Examples 1. soap 2. detergent b. Surface Tension: Force caused by attraction between like molecules that occurs at liquid-gas interfaces and that holds the liquid surface intact i. Units of Measure: dynes/centimeter (dyn/cm) 1. the force required to cause a 1 cm rupture in the surface film ii. a droplet forms because a liquid’s molecules are more attracted to each other than the surrounding…

Gram seeds embryo is called dicotyledons. Seed germination is the process i which the seed breaks a part and the embryo inside to grow with the help of water and a nutrients from the soil seed normally begins to germinates then they get an appropriate range of soil,temperature and when water and oxygen are available.During germination the seeds absorb water either through the micropyle(pore like opening) it is present or through the testa(outer seed coat) when it is permeable.The entry of…

In this unit of my 9th grade Physical Science, we are learning and experiencing with labs. In this week's experiment, my class did the paper towel lab. Here, we tested the quality of three different paper towel brands, Viva, Up&Up, and Bounty. Each lab group was testing for a certain quality of each brand, such as strength and absorbency. Through different experiments, each lab group came to the conclusion that one paper towel brand had more strength or better absorbency than the other two. My…

Catherine Delker Honors Chemistry – Yellow Blue Beaker Experiment Lab Report 8/20/15 Blue Bottle Experiment Problem: The purpose of this lab was to determine the oxidation rate of the Methylene blue solution when tested with varying amounts of solution. Background: The Blue Bottle Experiment is a classic demonstration of a Reversible oxidation-reduction reaction with an alkaline solution of glucose that acts as a reducing agent. It is known that, “Methylene blue speeds up the reaction,…

Sofya Tkachman AP Biology, A2 Dr. Lau 15 September, 2015 Enzyme Catalysis I. Purpose Measure the activity of catalase in potato extract using several different methods. II. Procedure a) Cut 20 small circles from a large filter paper disk using a hole puncher. Clean and dry several medicine cups and pour hydrogen peroxide into one. Put the catalase enzyme, previously prepared by blending a potato, into another medicine cup. Make a 1/8 dilution of the catalase by adding chilled distilled water.…

Homeostasis is defined as keeping the variables and conditions of a system constant and regulating the internal conditions. In a biological system at the cellular level, this can be defined as the process of maintaining stable conditions inside a cell, such as a normal pH, salinity, and ion concentration, to keep the cell healthy. There are several parts of the cell that play a role in homeostasis, but one of the more prominent ones is the phospholipid bilayer membrane. The cell membrane…

In this experiment, we set out to determine the osmolarity of a potato. In order to do this, we placed potato pieces in seven different solutions of varying sucrose molarity. First, we weighed each potato piece to obtain the initial weight, shown in Figure 1. Then, we split the pieces vertically before placing them in the cubs containing the sucrose solutions. In each cup was a solution of sucrose with a molarity ranging from 0.0M to 0.6M. After placing the potatoes in the cups, we allowed them…

Emma Kilgore Science Period 2 January 12, 2016 The Evaporation of Liquids When a liquid is left in a warm car over a certain period of time some people might notice that the liquid seems to have lessened. This is because of evaporation, evaporation is when a liquid changes into a gas because of an increase in temperature or pressure. This brings up many questions having to do with liquids and evaporation so, do all liquids take the same amount of time to evaporate?…

Abstract: Using the PhysioEx.9.1 software, I ran Activity 4: Simulating Filtration lab to learn about the filtration of solutes in a membrane system. This experiment was conducted using four solutes: NaCl, urea, glucose, and powdered charcoal. The goal was to learn if any of these solutes passed through the three different dialysis membranes at varying pressures. Does increasing the pore size increase filtration rate? What effect will pressure have on the filtration rate? These are the…