BIOC2580 Pre-Lab Quizzes PDF

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Pre Lab Quizzes BIOC2580...

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Quiz 1 ● It asked to draw glutamine, aspartate, leucine, HISTADINE. SERINE, Lys. ● asked what the purpose of the lab was and how you'd do it, ● Name the amino acids that have a benzene ○ Phenlyalanine, tyrosine, tryptophan ● name the two amino acids that have S in them, ○ Methionine and cysteine ● name the two amino acid isomers, ○ ^^ Does anyone know the answer to this?? ○ Im pretty sure its leucine and isoleucine ● label a diagram (figure 1.3 in lab) ● It also asks to name the general structures all amino acids have (amide group, carboxylate group, r chain) ● It also asks what would bind to anion exchange, which would be a negative amino acid ● Asks about unit conversion (uL, etc.) ● Amino acids are the building blocks of which macromolecules? ○ Proteins Quiz 2 ● explain the purpose of the lab to separate and quantify proteins (by using gel filtration column chromatography and bradford colorimetric assay) ● how does gel filtration work gel filtration separate molecules based on molecular size or weight. large molecule eluted first and then small ones. this is because large proteins cannot penetrate into aqueous space inside the beads. on the other hand small protein penetrate. ● 1.Draw 2 amino acids joined by a peptide bond (aspartyl-alanine) ● 2. What's the wavelength range visible to the human eye -->400 to 700 nm ● 3. What’s the beer-lambert equation and what do each of the variables stand for A=ϵlc A= absorbance (no unit) ϵ= molar extinction coefficient ( L mol-1 cm-1) l = thickness -> the path length (cm) c= concentration (mol/L) ● 4. What are the advantages of using a microplate reader over a conventional spectrophotometer. faster (96 sample in 5 sec), small volume of sample can be used, more precise

● 5. What are the units of absorbance-->Absorbance doesn't have any units because its the ratio of the amount of light that passes through a solution compared to the amount of light that is passed into it. Quiz 3 ● Ours asked what Km and Vmax were ○ = Km: The Michaelis constant. Equal to the substrate concentration [S] when Vo is ½ of Vmax ○ Vmax: rate of reaction when all active sites are filled by substrate - max velocity of the enzyme ● what the active unit for LDH is ○ = 1 enzyme activity unit for LDH = amount of enzyme that will reduce 1 micromole -of pyruvate to lactate per minute at neutral pH and room temperature (pH 7, 25C) ● what reaction we were carrying out ○ = Carrying out the conversion of pyruvate to lactate imitating a step of anaerobic glycolysis using NADH as a cofactor and LDH as an enzyme ● why we studied this reaction and not the reverse in lab ○ = We study this and not reverse because the reverse has positive delta G (positive gibbs free energy) so it’s not spontaneous like the forward reaction. ● what wavelength we were using and why, ○ = we are using 340 nm because NADH absorbs this wavelength well and NAD+ doesn’t and equal moles of pyruvate converted to lactate are converted from NADH to NAD+ so it can be used as a progress tracker for the reaction. ● and to draw a general michaelis-menten graph. Hope this helps (Figure 3.3 in lab manual) and are asked what Vo is ● Mine asked what kind of enzyme lactase was ○ Oxidoreductase ● Someone mentioned in the FB group we need to know “know the 4 chemical equation equations”

Lab 4 ● ● ● ● ●

the lab quiz i had was 1. purpose of the lab** 2. write the equation for first step of Wij's reaction** 3. define iodine number 4. Differences between cis and trans**

● 5. where is fat stored in the body ● 6. Unsaturated makes _________ membranes and saturated makes __________ membranes ● 7. Cause of atherosclerosis ● 8. How can one be healthier in relation to polyunsaturates/saturates ● 9. asked for the difference between cis and trans fatty acids (asked for 2 differences) ● What lipid is most common in humans?

Lab 4 Quiz Answers ● 1. The purpose is to determine the iodine number of a lipid sample, used to determine its degree of unsaturation and gives the ability to determine if the sample is a fat or oil. ● 2. HC=CH + ICl ---> CHI-CHCl . The ICl solution reacts with the double bonds in the unsaturated fatty acid to form a di-halogenated single bond ● 3. The amount of iodine in grams that is consumed by 100g of the lipid. ● 4. Trans has hydrogens on opposite sides of the double bond and is man made. cis has hydrogens on the same side as the double bond and occurs naturally Trans: -CvH=C^H- Cis:   -C^H=C^H● 5. I think the answer they were looking for is "in adipose or fatty tissue" ● 6. Unsaturated makes "Fluid-like" membranes and saturated makes "gel-like" membrane ● 7. Too much saturated fats hardening arteries ● 8. Increase P/S ratio by increasing plant consumption and decrease meat consumption ● triglycerides Quiz 5 ● 1.standard carb formula ● 2. 2 types of disaccharides ● 3. the organ that uses glucose for fuel ● 4. glucose storage for animals ● 5. glucose storage for plants

● 6. glucose cell that is in plant wall and type of bond ● 7. They also ask the functions of polysaccharides Quiz 5 Answers: ● 1. (CH2O)n ● 2. Lactose and Sucrose ● 3. The brain ● 4. Glycogen (do you mean the type of polysaccharide it's stored as?) ● 5. Starch (same note as above) ● 6. Cellulose connected by B-1,4 glycosidic links, ● 7. energy storage & structure strength

● 1. What is the purpose of today's lab? ○ To determine the weight percentage of reducing sugars in fruit juice ● 2. Name two monosaccharides ○ Glucose, galactose, ribose ● 3. Is lactose a reducing sugar? Why? ○ Yes, because it has an available C1 (to make aldehyde) for bonding ● 4. What is the polysaccharide storage in plants? ○ Starch ● 5. What is the Maillard reaction?

○ Reaction of a reducing sugar and amino acids to give browned foods their flavour. ● 6. What is the structure of polysaccharides in plants and how are they linked Cellulose, B-1,4 Glycosidic Linkage Hey guys i have my lab today and im totally gapping out on how to do question 1.. Do you have to convert concentration of glucose from ml/mg to moles before you calculate c2? Thank you!! No, you don’t have to convert the units… when solving for C2 the units for V1 and V2 (μL) will cancel each other out, while the units for C1 will remain the same (mg/ml)...