The Bile Esculin agar test has its medium as selective and differential. Black medium shows a positive result for esculin hydrolysis. In the agar, Gram-positive cannot grow in the presence of bile while certain Gram-negative bacteria can hydrolyze esculin with bile present. MR-VP broth contains glucose and peptone. The enteric bacteria will oxidize glucose for ATP, but there are different fermentative pathways that allow glucose to be fermented.
A lac operon is an operon required for the digestion of lactose in bacteria cells. B-galactosidase converts lactose, a disaccharide, into glucose and galactose, monosaccharides. The substrate for beta-galalactoside is ortho-nitrophenyl-B-galactoside. ONPG is structured similarly to lactose. The purpose of the experiment was to add a competitive inhibitor to observe if the reaction rate would slow down.
Nevertheless, small changes in enzyme activities and affinities could be observed. For instance, arsenate can cause hexokinase to work slower. Next Slide (with graph)- Attached is the graph that shows the difference between the enzyme activities when phosphorus is used and when arsenic is used. As you can tell, the enzyme activity decreases when arsenic is added. At the level of the Krebs cycle, it primarily inhibits enzymes that require lipoic acid as a cofactor, such as pyruvate and alpha-ketogluterate dehydrogenase.
The process of cellular respiration, cells extract the energy stored in the glucose molecule (Campbell & Reece, 2005). The molecule is a sugar that provides major fuel for cellular to work. But the carbon skeleton works on the row material for synthesis of all different verities of small organic molecules. For example amino acids and fatty acids. Such sugar molecules that are not immediately used are incorporated into disaccharides and polysaccharides.
Investigative Question: Does tap water, Powerade or orange juice contain more electrolytes? Hypothesis: Powerade will contain the most electrolytes as millions of Rands are spent on engineering these drinks to rehydrate athletes as effectively as possible. Variables: Independent: Orange juice, Powerade, distilled water, temperature
Introduction The purpose of this lab is to use control variables to help identify different macromolecules. Biological systems are made up of these four major macromolecules: carbohydrates, lipids, proteins and nucleic acids. Carbohydrates are sugar molecules (monosaccharides, disaccharides, and polysaccharides) which make them the most abundant macromolecule on the earth. Lipids (oils and fats, phospholipids and steroids) are insoluble in water and perform many functions such as energy source, essential nutrients, hormones and insulators (Lehman, 1955). Proteins are made up of peptide bonds holding amino acids together to perform biological functions like enzymes, antibodies, for transport and structure (Asmus, 2007).
Enzymes. Lipids (Lipase) Lipase are secreted by the small intestine and pancreas. They digest complex lipids (fats) molecules into simpler, more soluble fatty acid and glycerol molecules. They exist of fats and oils and are made up of the elements carbon, hydrogen and oxygen and the most common type known of is the triglyceride. A triglyceride is made up of 3 fatty acid chains joined to a glycerol molecule.
A amylase or B amylase are the enzymes of importance for bakers with A amylase being for dextrinising and B for saccharifying. A amylase splits starch molecules which produces dextrins of various molecular sizes. B amylase acts on the end of the starch molecule which releases maltose. B amylase cannot attack the starch molecules at the points it is branched. When A amlyase and B amylase work together they create a much better greater conversion into fermentable sugars ( glucose and maltose) rather than each amylase working alone.
Macromolecules like carbohydrates and proteins are organic molecules that support life. Enzymes are needed to break carbohydrates down into simpler components that can easily be used for energy. However, enzymes are very specific and only react to certain substrates, as shown by part A of this lab, where glucose trinder was exposed to glucose, galactose, mannose, and lactose, but only reacted with glucose. To show how pH can have an effect on enzymatic reactions, lactose was exposed to lactase at different pH 's, the data showed that the reactions occurred more easily at the more neutral pH 's (closer to a pH of 7). Background: Macromolecules are organic molecules that are necessary for life, these molecules include nuclei acids, carbohydrates, proteins, and lipids.
Disaccharides There are three dietary monosaccharides called glucose, fructose, and galactose. Monosaccharides are single-ring structures, and they form the basic building blocks for more complex sugars, such as disaccharides. Disaccharides are referred to as double sugars because they are made from a combination of two monosaccharides. In dehydration synthesis, water is removed and two monosaccharides become a disaccharide. Dehydration Synthesis, or condensation reaction, is when we can take these single-ring structures and combine them by taking away water, or H2O.