Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Lab Midterm Biology
Lab Midterm Biology Questions
| Question | Answer |
|---|---|
| It is possible for measurements to be precise but _______. | Inaccurate |
| The degree of accuracy can vary between each measurement. Therefore, quantitative data is not always ________. | Accurate |
| Which statistical value is best for determining accuracy of a tool? Standard Deviation Percent Standard Deviation Percent Error Mean | Percent Error |
| What type of molecule CANNOT be separated using gel electrophoresis? Lipid DNA RNA Proteins | Lipid |
| What kind of molecules are separated by gel electrophoresis? | Positively and negatively charged molecules. |
| Which kind of molecules CAN'T be separated by gel electrophoresis? Why? | Neutrally charged molecules can't be separated because they won't be attracted by the cathode or anode in the electrical field. |
| What process occurs to red blood cells in a hypertonic environment? | Crenation |
| What is the range of volume a p100 micropipette can hold? | 10 to 100 microliters. |
| What is the range of volume a p20 micropipette can hold? | 2 to 20 microliters. |
| What is the range of volume a p2 micropipette can hold? | 0.2 to 2 microliters. |
| What is the range of volume a p1000 micropipette can hold? | 100 to 1000 microliters. |
| Which structure is NOT visible in an Elodea cell under a light microscope? | Mitochondrion |
| What chemical reagent is used to detect starch in a sample? | IKI solution. |
| What chemical assay is used to detect reducing sugars? | Benedict's test |
| What chemical assay is used to detect proteins? | Biuret test |
| What chemical assay is used to detect lipids? | Sudan IV test |
| Which molecule is permeable to dialysis tubing? Starch Glucose Albumin DNA | Glucose |
| What is a positive result of the Buriet Assay? What is a negative result? | A positive result of the Buriet Assay turns the solution violet. A negative result turns the solution light blue. |
| What electrode do positively charged molecules move towards in gel electrophoresis? What about negatively charged molecules? | Positively charged molecules move toward the cathode and negatively charged molecules move toward the anode. |
| What happens when the pH of a solution decreases? What happens when it increases? | The solution is gaining H+ ions if the pH is decreasing. If it is increasing, the solution is gaining OH- ions. |
| What are the building blocks of nucleic acids? | Nucleotides |
| What are the building blocks of carbohydrates? | Monosaccharides |
| What are the building blocks of lipids? | Fatty acids and glycerol |
| What are the building blocks of proteins? | Amino acids |
| Select the correct pairing of macromolecule and its building block. Glucose/Cellulose Nucleotide/Protein Glycerol/Starch Amino acids/DNA | Glucose/Cellulose |
| Select the correct pairing of chemical assay and its positive control group. Buriet/DNA Benedict's reagent/Glucose IKI/Albumin Sudan/Glycerol | Benedict's reagent/Glucose |
| Which is the correct statement about microscope? Ocular magnification power is always 1X. Low power objectice is 4X. Field of view decreases as magnifcation power increases. Condenser decreases contrast of a sample. | Field of view decreases as magnification power increases. |
| What drives the movement of all molecules across the dialysis membrane? | The concentration gradient across the dialysis membrane. |
| How do you calculate the total magnification of a specimen? | By multiplying the ocular power by the objective power. |
| What is the purpose of setting up two sets of test tubes for benedict's test? | To provide a negative control color standard for comparison. |
| What does the standard deviation range do? | Determines the precise data within the data set. |
| Which feature can be reliably used to differentiate an animal cell from a plant cell? Position of the nucleus. The presence of a cell wall. Absence of chloroplasts. Size of the cell. | The presence of a cell wall. |
| What is the diameter of the field of view when using the scanning objective (4X) | 4500 micrometers |
| Are hydrophobic molecules polar or nonpolar? | Nonpolar |
| Are hydrophilic molecules polar or nonpolar? | Polar |
| Name four purposes of using a buffer in gel electrophoresis. | To apply the electrical field, provide the necessary ions to conduct electricity, maintain the pH levels, and to maintain the temperature. |
| Does voltage and temperature have any relationship? | No, voltage does not affect the temperature of a solution. |
| What is the diameter of the field of view when using the low power objective (10X)? | 1800 micrometers |
| What is the difference between organic and inorganic molecules? | Organic molecules are found in living things and contain carbon. Inorganic molecules are not found in living things and don't have any carbon atoms. |
| Why do negative assay results not always mean the molecule is absent? | A negative result may just be negative because the concentration of the molecule is too low to be detected. |
| What is the fluid mosaic model of a plasma membrane made up of? | Lipids, proteins, and carbohydrates. |
| How do you detect nucleic acids? | Gel electrophoresis |
| How many times is an object magnified when using the low power objective (10X)? | 100X |
| What is the diameter of the field of view when using the high power objective (40X)? | 500 micrometers |
| How do you measure the estimated object size? | Diameter of the chosen field of view divided by the estimated number of the object across the field of view. |
| Does diffusion require a membrane? | No, this process does not require a membrane. |
| What is the physical state(s) of molecules moved by diffusion | Solid, liquid, and gas. |
| Does osmosis require a membrane? | Yes, this process requires a semi-permeabe membrane. |
| What is the physical state(s) of molecules moved by osmosis? | Liquid |
| Which molecules are macromolecules? Starch Albumin Chloride Ion Glucose | Starch and Albumin. |
| Why is it important to thoroughly rinse the outside of dialysis tubing with DI water to remove any trace of solution A before you place the tubing into the beaker and fill it with solution B? | Solution A can remain on the outside of the tubing and lead to false positive results at the end of the experiment. |
| What solute concentration is isotonic for blood cells? | 1% solute concentration |
| What would happen if the glucose concentration within blood plasma became 1.2%? What direction would water flow and what would happen to the cell shape? | It would become hypertonic and begin to crenate. This is due to the water flowing out of the cell due to osmosis. Since water is flowing out of the cells, this will cause the cells to shrivel into an irregular shape. |
| What drives the movement of all the different molecules across the dialysis membrane? | Potential energy stored in the concentration gradient pushes molecules across the dialysis membrane through passive transport. |
| Why would some molecules in a solution fail to move across the dialysis membrane? | The dialysis membrane is selective of molecules that can pass through its pores found within the wall of the membrane. These pores only allow small molecules to pass through, so large molecules would not be able to pass. |
| The hydroxyl group will allow what type of bonding to take place in ethanol? | Hydrogen bonding |
| What reaction is the hydroxyl group needed for? | Dehydration reaction |
| What is the function of the aldehyde group when the hydrogen is removed? | It can be oxidized to form carboxylic acids. |
| With the hydrogen on the aldehyde group, what reaction can the group participate in? | Condensation reaction |
| Why is hydrogen bonding not possible with aldehyde? | The hydrogen is not attached to the oxygen. |
| What charge does the oxygen attract in the carbonyl group? What about the carbon? | The oxygen attracts positive charges while the carbon attracts negative charges. |
| Why can't the carbonyl group participate in dehydration reactions? Can this group participate in condensation reactions? | This group can participate in condensation reactions, but NOT dehydration reactions since it lacks hydrogen. |
| Can molecules containing to carbonyl group hydrogen bond? How? | Yes, by being a hydrogen bond acceptor. |
| Can the carboxyl group participate in condensation reactions? | Yes, it can participate in condensation reactions. |
| Why is the carboxyl group acidic? | Because COOH ionizes to become COO- and H+. |
| Is hydrogen bonding possible with the carboxyl group? Why? | Yes, because of the OH part of the group. |
| Does the amino group absorb or donate H+ ions? What is the result of this? | It absorbs H+ ions, making the group basic. |
| How does the amino group engage in condensation reactions? | By giving up H+ ions. |
| What is the chemical formula of an amino group existing in a solution? | NH3+ |
| Is hydrogen bonding possible with the amino group? Why? | Yes, because of the very polar N-H bond. |
| Is hydrogen bonding possible with the phosphate group? Why? | Yes, because the oxygens in this group often carry hydrogens on them. |
| How are nucleic acids formed through the phosphate group? | The OH bond in this group can engage in dehydration reactions. |
| Is the phosphate group nonpolar or polar? Why? | It is technically nonpolar because the four oxygens on the phosphorous creates a perfectly balanced symmetry. |
| Is a molecule containing a phosphate group hydrophilic or hydrophobic? Why? | It is hydrophilic because this group is an ionic functional group. |
| What are disulfide bridges used for? | To secure the 3-D structure of protein molecules. |
| Which is more hydrophilic and why? A molecule containing the sulfhydryl group. A molecule containing the amino group. | A molecule containing the amino group is more hydrophilic because the amino group is an ionic polar function group while the sulfhydryl group is only slightly polar. |
| Are molecules containing polar functional groups typically hydrophilic or hydrophobic? | Hydrophilic |
| Are molecules containing nonpolar functional groups typically hydrophilic or hydrophobic? | Hydrophobic |
Created by:
Inkie27
Popular Biology sets