Formulation, Testing of Hypothesis, and Experimental Design

Biology Lab 6 Please answer these questions then place them in the drop box for this lab. Use Microsoft word if possible. Lab 6: Diffusion 65 Questions 1. Which dye diffused the fastest in corn syrup? Red Dye In your chosen material? Lemon Concentrate, Blue Dye 2. Does the rate of diffusion correspond

2. Explain your observations in detail in terms of concentration gradient, diffusion, osmosis, osmotic pressure, passive transport, and active transport.

Review Sheet 1 Results 1. Describe two variables that affect the rate of diffusion. Your answer: Two variables that affect the rate of diffusion are the MWCO membrane and the solute concentration. Increasing the membrane size and solute concentration will also increase the average diffusion rate. Decreasing the membrane size and solute concentration

For Learning Centre use only Activity 1: Simulating Dialysis (Simple Diffusion) Lab Report Review Sheet Results 1. 2. 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 diffuse more slowly than the smaller molecule.

Osmosis in a Decalcified Egg to Determine the Glucose Content of an Egg Tovah King C62 7/5/2017 Abstract: Diffusion is the transfer of molecules from an area that has a higher concentration to an area that has a lower concentration. Osmosis is the diffusion of water. The purpose of this experiment was to study the process of osmosis. In order to test osmosis, eggs that had been soaking in vinegar were taken and placed in four beakers of solution with different levels of glucose. Using this experiment we were able to determine the rate of osmosis of different solutions, with various amounts of glucose, through eggs. In the results of this lab it was found that the eggs were either hypertonic or hypotonic and that the

Danisha Stewart April 18, 2012 Research Article Critique 1 NURS 4922 1. Brodaty, H., Ames, D., Snowdon, J., Woodward, M., Kirwan, J., Clarnette, R., & ... Greenspan, D. (2005). Risperidone for psychosis of Alzheimer's disease and mixed dementia: results of a double-blind, placebo-controlled trial. International Journal of Geriatric Psychiatry, 20(12), 1153-1157.

Part A: Title: Diffusion Diffusion is the spontaneous movement of particles from where they are more concentrated to where they are less concentrated. For this experiment, a 14 cm glass was filled with cold tap water. A drop of red food coloring was dropped in the cup. A stopwatch was used to measure the time it took for the food coloring to get to the bottom of the cup. The average diffusion rate was .78 cm a second. If a different color was used, I do not think it would have made a difference in the results. The mood of the person experimenting could possibly alter the results. For example, if a person is under stress, they may accidentally squeeze too much altering the rate of diffusion. If the water was warmer, this may have sped the

The following hypothesis was made in regard to effect of the concentration gradient on the rate of diffusion: The higher the concentration gradient, the faster the rate of diffusion.

The difference is that along with large molecules, living cells prevent molecules with positive charges and solubility. This is not representing in dialysis tubing, and is only found in living cells because the tubing is only based on molecular size (98). When referring the rate of diffusion, the concentration gradient influences the diffusion rate, based on the factors of temperature. The ability for molecules diffuse from high to low concentrations primarily depends on the concentration gradient between the two areas.(96-99). My hypothesis for the study is that in the hypotonic, hypertonic, and isotonic solutions, the direction and rate of osmosis will determine based on the concentration inside the dialysis tubing. My prediction is that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant.

BACKGROUND A cell needs to perform diffusion in order to survive. Substances, including water, ions, and molecules that are required for cellular activities, can enter and leave cells by a passive process such as diffusion. Diffusion is random movement of molecules in a net direction from a region of higher concentration to a region of lower concentration order to reach equilibrium. Diffusion does not require any energy input. Diffusion is needed for basic cell functions - for example, in humans, cells obtain oxygen via diffusion from the alveoli of the lungs into the blood and in plants water

LAB EXERCISE: Diffusion and Osmosis Laboratory Objectives After completing this lab topic, you should be able to: 1. Describe the mechanism of diffusion at the molecular level. 2. List several factors that influence the rate of diffusion. 3. Explain why diffusion is important to cells. 4. Describe a selectively permeable membrane, and explain its role in osmosis. 5. Define hypotonic, hypertonic, and isotonic in terms of relative concentrations of osmotically active substances. 6. Discuss the influence of the cell wall on osmotic behavior in cells. 7. Explain how incubation plant tissues in a series of dilutions of sucrose can give an

Abstract Cells and molecules in the environment are constantly moving and changing, for cells to function properly there is a need for equilibrium to be met. The size of the cell and the solution outside of the cell affects the rate of diffusion and osmosis in the cell. Cells are constantly trying to reach an equilibrium with the molecules and substances around it, which is why there are such terms as: hypertonic, hypotonic and isotonic. The procedures allowed testing of whether or not surface area or volume increased diffusion and how different substance control diffusion. Cells are constantly moving to reach equilibrium through diffusion and osmosis.

INTRODUCTION A major determinant of diffusion in a biological system is membrane permeability. Small, uncharged molecules pass through cellular membranes easily, while most and/or charged molecules cannot pass through the membrane. The movement of water across a selectively permeable membrane, like the plasma membrane

INTRODUCTION: DIFFUSION OF DYE THROUGH AGAR GEL Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration. The rate at which molecules diffuse can be determined by the relationship of molecular weight and that rate of diffusion through a membrane. Hypothesis of this experiment is that the fluid with higher molecular weight will diffuse at a slower rate and distance.

Diffusion is random movement of molecules or other The next experiment was to test diffusion in agar solution. A petri dish with a layer of solidified agar had four holes punched in it using a No. 5 cork borer. Three holes were punched in a triangle shape with the fourth hole directly in the middle. There should be 15 mm between each outside hole and the middle hole. The three outside holes were filled with one drop each of potassium bromide, potassium Terri cyanide, and sodium chloride. The middle hole was filled with a drop of silver nitrate. It is very important to make sure that none of the holes overflow. After each has been filled allow to sit for an hour and observe the results.