I. Introduction/Background/Purpose/Hypothesis Essays - Catalysis

I. Introduction/Background/Purpose/Hypothesis: BACKROUND: An enzyme is a protein that controls the chemical reactions that take place in the body. Enzymes help by catalyzing (speeding up) the reaction and intern lowering the activation energy required for the reaction to occur. Molecules called substrates bind with enzymes during reactions. However each enzyme has a very specific purpose. The shape of the active site on the enzyme's outer layer determines that purpose, along with deciding which substrates can bind with that specific enzyme. The active site of the enzyme is the spot where the substrate binds in order for the reaction to occur. The bond formed by the enzyme and substrate is a noncovalent chemical bond that exists little more than a millisecond. However, while bonded the substrate undergoes a chemical change and is converted into the product of the reaction. While held together by this weak bond the enzyme-substrate complex is formed. When the reaction is over this complex breaks down and the product leaves the enzy me and is used by the cell. Then enzyme returns to the catalytic cycle unchanged and it waits to be used again. Any one enzyme may be used over a thousand times per second: in turn requiring very little amounts of enzyme to convert large amounts of substrate into product. Since they are used at such an extreme pace enzymes do wear out and denature. Cellular proteinases are what cause the denaturation of the enzyme. The enzyme is then changed into the most basic amino acids and is used to make other proteins. The balance of the following determines enzyme amount: the process, which degrade the enzyme, and the processes that synthesize the enzyme. If a chemical reaction requires an enzyme to occur and none are present, than the rate of the reaction is very slow. However, if the amount of enzyme concentration is increased in a chemical equation than the catabolic rate is also increased. PURPOSE: The experiment we are going to investigate is meant to determine the effects of temperature on the activity of the enzyme. We will test temperatures ranging from 4?C to 48?C to find out if extreme temperatures either increase or decrease enzyme activity. Four different compounds will be tested, each having a different temperature, in order to determine what, if any, affect those temperatures will have on the enzyme activity. Comparing the color change in the substances will monitor enzyme activity. These color changes will be observed according to their absorbency of light. The absorbency will be monitored using a spectrophometer. Each compound will be tested several times to get an average set of data. This is done in order to avoid skewed results. All raw data will be recorded in table 1.1, and displayed by a graph. The averages will be recorded in table 1.2 and then displayed in there own graph. The averages will be used to get standard deviations. Those figures will be d isplayed in table 1.3 and also displayed in a graph. HYPOTHESIS: Enzyme activity will be increased as the temperature changes. However, at the extreme temperatures the enzyme activity will decrease. One thing should be kept in mind however, this experiment uses peroxidase as its enzyme, but every enzyme has a different optimal temperatures. II. Materials/Method: MATERIALS: 9 test tubes, 2 hot water baths (one at 32?C and one at 48?C), Refrigerator, 30 ml guaiacol, 30ml H2O2, 30ml turnip extract, 30ml of Ph5 stock solution, spectrophometer, micro-pipet, roller pipet, 2 test tubes racks, 2 cuvets, cuvet rack, kim wipes, timer, gloves and goggles, distilled water, micro-pipet tips, sharpie METHOD: 1) Pre-incubate water baths to correct temperatures 2) Label test tubes 1-9 with Sharpie marker 3) Mix test tubes according to table 4.3 on page 4-9 of lab manual 4) Calibrate spectrophometer, according to directions given on page4-5 figure4.3, using test tube number 1 (the control) 5) Mix test tubes 2 & 3 and record absorbency every twenty seconds for 2 minutes. (be sure to start timing as soon as test tubes are mixed being mixed) 6) Mix test tubes 4 & 5 and record absorbency every twenty seconds for 2 minutes. (be sure to start timing as soon as test tubes are mixed being mixed) 7) Mix test tubes 6 & 7 and record absorbency every twenty seconds for

Second-Grade Goals for Students After the New Year

Second-Grade Goals for Students After the New Year In order to hit developmental benchmarks, it helps to have parents on your side. These are a few second-grade goals for students to complete after the new year. Share them with parents during conferences so they will have a rough idea of the expectations you have for their child. All children learn differently and are not alike, but it helps to have a few general goals listing which skills students will need to know by the end of the school year. Goals to share with parents should include a focus on reading, math, writing, and what to work on at home. Reading Goals Second-grade students should be able to recognize words as chunks, not just individual letters. For example when looking at the word cheat, the second-grade student should be able to recognize the word eat. Other reading goals include: Increase reading fluency and expression.Use punctuation appropriately.Identify an increasing number of words by sight.Be able to identify the speaker in a story.Retell a story by providing details. Students should also be able to use graphic organizers- visual and graphic displays that organize ideas and demonstrate relationships between different information and concepts- to show an understanding of story elements such as the main character, plot, main idea, supporting details, setting, solution, and theme. Additionally, second-grade students need to strengthen their comprehension skills when reading independently.  They should  be able to identify the main idea in the story as well as locate supporting details, infer, and be able to answer text-specific questions. (This is now a part of the  common core.) Math Goals Second-grade students must able to simplify word problems and directions when needed. They need to have the ability to take their time and work through a problem until it is completed properly. Other math goals include: Recite 25 math facts in one minute.Understand math vocabulary and recognize it. For example, they must be able to recognize what the question is asking, such as: What is place value?Use appropriate tools to strategically to solve a problem.Mentally calculate sums and differences for numbers with only tens or hundreds.Develop a foundation for understanding area and volume.Be able to represent and interpret data. Additionally, second-grade students should extend their understanding of the base-10  system. Writing Goals By the end of second grade, students must be able to capitalize and punctuate correctly and use punctuation to add effect to their writing. Second-graders should also be able to: Provide a strong beginning that will grab the readers attention.Create an ending that will show that their writing piece is finished.Use strategies to plan writing, such as brainstorming and using graphic organizers.Show their personality through their writing.Use a dictionary to self-correct during the drafting phase.Add details to support the main idea. Additionally, students should begin to use transition words in their writing to construct logical order, such as first, second, and third, or next and finally. At Home Goals Learning does not end in the classroom. While at home, students should: Practice math facts- three to five facts at a time- each night or at least five times a week.Study spelling patterns and practice spelling words in a variety of ways besides memorization.Read independently for at least 10 to 15 minutes each night.Have plenty of age-appropriate books available to help them develop vocabulary skills.Work with their parents to develop study skills that will last a lifetime. Even at home, children should use punctuation correctly and write in complete sentences in letters, shopping lists, and other writing.