What is the function of the iodine solution in the Gram stain? If it were omitted, how would staining results be affected? Iodine is used as a mordant, it combines with the dye in the Gram Stain. 2. What is the purpose of the alcohol solution in the Gram stain?
Exercise 4: Some metabolic activities of bacteria 1. What is the color of phenol red at an acid pH? 2. What is the function of a Durham tube? 3.
Mitosis In this experiment, I learned to make my own cheek cell slide to view under the microscope, and I also viewed fish cells under the microscope The purpose of this was to become familiar with a microscope and it's features, as well as, find and identify cells and the stages of mitosis. In doing so, I was able to differentiate between the different stages of mitosis from Interphase to Telophase. Materials: 1 Microscope 1 slide 1 slide cover 1 drop blue dye 1 tooth pick 1 slide with fish cells 1 camera phone 1 pen 1 piece of paper (in lab manual) Method: Cheek Cells First I took a toothpick and swabbed the inside of my cheek for a few moments. I then rubbed the toothpick on the slide, put one drop of blue dye on top of the slide, then covered the saliva/dye mixture with the slide cover. After that, I placed the slide under the microscope and began searching for the cells that were on the slide.
Blanca Mbuto 02/19/2012 Biochemistry Lab 4422 Cell Fractionation by Centrifugation Abstract This experiment was performed to investigate organelles, membranes, cellular components, and enzymes. Our concentration was to observe and determine if the chlorophyll contained broken chloroplasts or intact chloroplasts extracted from spinach leaves. A percoll density gradient was prepared followed by the separation of organelles. Chlorophyll was analyzed by using a spectrophotometer. We compared the absorbance readings of each tube and selected three (3) tubes to be analyzed.
Chemistry PAT Question 1 Polyhydroxybutyrate (PHB) is a biopolymer with properties very similar to that of polypropylene, though has all the benefits that come with biopolymers. PHB was first introduced to the scientific community by the scientist Maurice Lemoigne in 1926. He noticed that to produce PHB you need particular micro-organisms such as Alcaligenes Eutrophus or Bacilius megaterium undergoing physiological stress in an apparatus such as an agar dish to allow the micro-organisms to multiply. In order to achieve this stress there is a restriction to the amount of nitrogen the micro-organisms can attain thereby altering its nutrition. This is quite an efficient method of production and the amount of the PHB polymer yielded is around 30-80% of the dry weight of the micro-organisms used.
Nuclear envelope What genetic material is found in this part of the cell more than anywhere else in the cell? RNA C. Nucleolus D. Cytoplasm E. Mitochondria F. Lysosomes G. Endoplasmic Reticulum H. Golgi apparatus I. This part of the cell is reponsible for breaking down organic molecules. J. Ribosomes K. centrioles L. Chromatin What function do peroxisomes serve? Peroxisomes contain a variety of enzymes, which primarily function together to rid the cell of toxic substances, and in particular, hydrogen peroxide (a common byproduct of cellular metabolism).
The type of cell tissues on my hand is epithelial tissue. 2. The iodine stain on the onionskin made the cells more visible. 3. The holes in the cell membrane are to small to see and materials can’t travel through them.
Aasir Osman Enzyme Investigation - Effects of pH on the Activity of Catalase Aim: The aim of this investigation is to determine the effect of the inhibitor which is pH, on the enzyme catalase, which can be obtained from potatoes. *************8 Introduction: Enzymes are proteins that catalyse the speed of biochemical reactions in the body. They are responsible for all metabolic functions and are absolutely vital for life itself. Without enzymes, reactions would take place too slowly to keep you alive. These proteins are highly specific regarding what they do and under what conditions they do it in.
Most differential stains have a challenge step that follows staining with a primary dye. In the Gram stain the challenge step is a rinse with either ethanol or acetone (either may be used). This step dehydrates and tightens the cell wall of Gram positives (mainly peptidoglycan) such that the rinse does not enter the cell. Gram negatives have mainly a lipid cell wall (even though they do contain peptidoglycan) that allows the challenge rinse to penetrate the cell and rinse out the crystal violet-iodine complex rendering the Gram negative cell colourless. Thus, the Gram negative cells must be stained to be seen, and this is done with the counter stain.
Gel Filtration of Proteins Session 4 Lab Report Semester 2 Victoria Franks 2930499 Gel Filtration of Proteins Introduction The aim of this experiment was to separate a range of proteins from a single sample, using their differing sizes to tell which protein was which when passed through a gel barrier. This method is called size exclusion chromatography. A range of coloured proteins and dyes are used so that samples can be easily idenitifed by the naked eye; however, two of the proteins are a similar colour, making it necessary to use spectrophotometry to tell the difference between them, based on the fact that they have different levels of absorbancy. A gel called Sephadex is used within a tight column and the protein sample is passed through using a strong buffer to help the smaller molecules of the protein sample to diffuse into the gel. As the Sephadex forms a network with tiny holes, this prevents molecules that are too large from getting inside.