Bio Lab Prelab ?'s

What cell structures were identifiable when viewing the Elodea cell in Lab 1?

-cell wall -chloroplasts

How to set Kohler

-focus specimen -close field diaphragm -adjust height of condenser until leaves of the field diaphragm are in sharp focus -use condenser centering screws to move the image of the field diaphragm to the center -open field diaphragm

the process of science

-generate hypothesis -design experiment -collect data -interpret data -repeat

How does the structure/size/number of white blood cells reflect their function?

-number of white blood cells indicates disease presence in a human body, so there are far less white blood cells than red blood cells in a healthy human

How does the structure/size/number of red blood cells reflect their function?

-red blood cells are small and can easily change shape and are smooth b/c fit through various blood vessels throughout human body -carries O2 from lungs to body then brings CO2 back from the body to the lungs

compare/contrast size, structure and number of red and white blood cells

-size: white blood cells are larger than red blood cells -structure: -white blood cells: round but not smooth -contain nucleus -red blood cells: smooth round shape -no nucleus -number: way more red blood cells than white

Abbe Equation

-tells the resolving power of an object -d = 0.612λ / NA

How can you actually determine the pH of a solution?

-use pH paper -use pH meter

how to focus an object under the microscope

1. begin with low power objective 2. sketch observations 3. take digital pictures

how many μm are in 1 r.u. at the 10X objective?

10 μm/r.u.

what does the ocular or eye-piece lenses usually magnify at?

10X, 15X, or 20X

how many μm are in 1 r.u. at the 40X objective?

2.5 μm/r.u.

how many μm are in 1 r.u. at the 4X objective?

25 μm/r.u.

objective lenses in revolving nose piece

4X: lower power (scnanning lens) 10X: medium power 40X: high power 100X: high power/oil immersion

During lab this week, you will study tyrosinase activity by monitoring the color of the solution. As the reaction proceeds (and DOPA is oxidized), the concentration of dopachrome should increase in the solution. How should the solution change in color over time? A. The solution will become a darker orange/brown. B. The solution will become a darker red. C. The solution will turn pink. D. The solution will become clear. E. The solution will not change color.

A

In BIO206L you will be introduced to procedures that should be mastered by practically all cell and molecular biologists. To help you master these procedures, the BIO206L team uses LabClicker (shown above). You will find links that connect you to videos and tutorials that will help you prepare for each exercise. You will also find Lecture Slides and your Lab Analysis assignments posted on LabClicker. The information on LabClicker will be updated continuously throughout the semester so check it frequently. To use LabClicker, you must register using your UTEID online at http://labclicker.com and pay a $35 plus tax registration fee. Take time to explore LabClicker before answering the question below. Which of the following items are available on LabClicker? A. All of the choices are correct B. Lecture notes C. Lab Analysis assignments D. Useful videos and links E. The course syllabus and schedule

A

Optical lenses of a high quality microscope are cleaned with: A. lens paper B. Kim-wipes C. paper towels D. Any of the above

A

Stains are often applied to a microscopic specimen mainly to increase or improve which aspect of light microscopy? A. improve contrast B. decrease resolution (increase d) C. decrease diffraction D. minimize artifacts/aberrations E. all of these answers

A

Sterile 15-mL conical tubes and straws are used for collection of rinsate containing human cheek cells. These are considered to be what? And must be safely discarded where? A. biohazards... in the Solid Biohazards/ Bacterial Waste. B. sharps... in the Sharps container. C. toxic materials... in the Solid Chemical Waste. D. nontoxic materials... in the regular trash. E. biohazards... in the Solid Chemical Waste.

A

This week in lab you will use the SpectroVis Plus Spectrophotometer to measure the light that is absorbed by dopachrome, a dark orange/brown molecule. Is a solution that appears dark orange in color absorbing orange wavelengths of light? A. No, it is reflecting orange wavelengths of light B. Yes, it is absorbing orange wavelengths of light

A

After 30 cycles of PCR, how many copies of the target sequence can potentially be produced from a single starting molecule of DNA? A. a few hundred B. 1 billion C. 1 million D. 1 thousand E. 30

B

As outlined in your lab manual, you are to view all of the following specimens with various types of microscopy EXCEPT: A. diatoms in a prepared mount. B. a wet mount of your red blood cells. C. a wet mount of your stained buccal cells. D. a wet mount of your unstained buccal cells. E. a prepared mount of bovine pulmonary artery endotheial cells.

B

Each PCR cycle has three main steps which repeat many times. All of the following were required for this PCR process EXCEPT A. deoxy-nucleoside triphosphates (dNTPs) and Mg2+ as a cofactor B. heat to denature enzymes and provide energy for the reaction C. specific single-stranded DNA primers and template DNA D. heat-tolerant DNA polymerase such as Taq E. buffer of the correct pH and concentration

B

Enzymes: A. make endergonic reactions proceed spontaneously B. lower the activation energy of a reaction C. are not very specific in their choice of substrates D. are needed in large quantities because they are used up during catalysis E. are unaffected by changes in pH or temperature

B

Köhler Illumination is used for what purpose? A. To focus the light to the smallest point on the specimen B. To provide optimal illumination across the field C. To decrease contrast, therefore allowing better focus D. To increase illumination across the field E. To increase magnification

B

The "slider" of the Olympus CX31 "student" microscope condenser provides the ability to perform all of the following types of microscopy except... A. Phase contrast microscopy B. Fluorescence microscopy C. Light microscopy D. Brightfield microscopy E. Darkfield microscopy

B

The Master Mix consists of which of the following components? A. Taq DNA polymerase, dNTPs, MgCl2, Primers B. Taq DNA polymerase, dNTPs, MgCl2, Buffer solution C. Taq DNA polymerase, dNTPs, MgCl2, Helicase D. Taq DNA polymerase, dNTPs, MgCl2, Template DNA

B

The component of an optical microscope that is altered most in converting from brightfield optics to darkfield or phase contrast optics is the: A. objective lens B. condenser C. oculars D. stage

B

The design of DNA primers is essential for a successful PCR experiment. For example, D1S80 primers can be used to amplify target sequences from which of the following DNA sources? A. a locus found on all human chromosomes B. a locus found on human chromosome 1 C. a locus found on bacterial plasmid DNA D. a locus found on bacterial chromosomal DNA E. a locus found on human mitochondrial DNA

B

The use of antibodies in fluorescence microscopy is a technique known as: A. autofluorescence B. immunofluorescence C. antifluorescence D. dichroic fluorescence

B

What does it mean for a cell to be competent? A. The cell is lysed by CaCl2 B. The charges on the phospholipid layer are neutralized by CaCl2 to allow the cell to uptake DNA C. The cell is made non-pathogenic D. The cell is able to accept DNA from a viral vector E. The charges on the phospholipid layer are neutralized by CaCl2 to allow the cell to uptake proteins

B

What does it mean that a bacterial cell has been transformed? A. It has replicated its chromosomal DNA B. A plasmid has been inserted into the cell C. A restriction enzyme has cut the chromosomal DNA D. The cell has divided E. The cell has been streaked onto an agar plate

B

What is the definition of pH? A. Percentage of H+ ions in a solution B. Negative log of the H+ concentration of a solution C. Concentration of H+ ions in a solution D. Negative log of OH- concentration of a solution E. None of these answers

B

Where do you place used glass 10-mL pipets? A. Back in the metal tin on the supply cart B. The pipet wash container located at the back of the room C. Glass disposal receptacle D. Wash them and leave them in the sink E. None of these answers

B

Which example in the video demonstrates proper parafilm technique? A B C D E. None of these examples demonstrate proper parafilm technique.

B

n the presence of oxygen, the enzyme TYROSINASE catalyzes the oxidation of DOPA (3,4-dihydroxyphenylalanine), producing dopaquinone. Dopaquinone spontaneously converts into dopachrome (a dark orange/brown molecule). Here is a simple diagram that illustrates this reaction: DOPA + O2 ⇒⇒⇒TYROSINASE⇒⇒⇒ Dopaquinone ≈ Dopachrome (orange/brown) Which of the following statements best describes tyrosinase? A. A product of an enzymatic reaction B. A polypeptide chain with active sites that bind DOPA and Oxygen C. A substrate that is converted to dopachrome D. A coenzyme that binds to oxygen E. An inhibitor that prevents oxidation

B

Considering that micropipetters are most accurate when delivering volumes of 50-100% of their total capacity, which micropipetter(s) would you choose to MOST ACCURATELY dispense a volume of 125µL? A. Both P200 and P1000 B. Both P10 and P200 C. P200 D. P10 E. P1000

C

Restriction enzymes A. assist in copying plasmid DNA at restricted sites. B. assist in copying chromosomal DNA at restricted sites. C. naturally restrict the bacterial growth by breaking down. D. restrict antibiotics from entering cells (anti-biotic resistance). E. cut double-stranded DNA only at specific nucleotide sequences.

C

The correct order of steps in a typical PCR cycle is: A. elongation - Annealing - Denaturation B. not important as long as all 3 are completed in each cycle C. denaturation - Annealing - Elongation D. depends on the primer and/or template DNA sequence E. annealing - denaturation - elongation

C

The main purpose of repeating the three steps (denature, anneal, extend) in a PCR protocol for multiple cycles (typically 30-40) is to A. reduce the number of primers. B. reduce the amount of dNTPs. C. amplify the amount of target DNA sequence. D. denature the template strands. E. All of the above.

C

The property of some compounds to absorb light at a given wavelength and shortly thereafter emit light at a slightly longer wavelength is called: A. Absorbance B. Stokes' Reflectance C. Fluorescence D. Any of the above

C

The total magnification through a compound microscope is equal to the magnification of the _____ times the magnification of the _____. A. ocular / condenser B. eyepiece / ocular C. ocular / objective D. objective / tube E. None of these answers

C

To help you prepare for lab, we require you to complete Lab Prep Assignments. You will be responsible for completing your Lab Prep Assignments using LabClicker. In some cases, you will watch a video or animation or demonstation and answer questions pertaining to the demonstration or lab technique that was presented. *You must be able to view YouTube videos on your device. Lab Prep Assignments must be completed PRIOR to the start of each lab according to the deadline posted in LabClicker. Lab Prep Assignments are not "timed". You can spend as much time on them as you wish until the due date. You only have one attempt to answer a question. To avoid server congestion/latency issues you will always want to submit your answers well BEFORE the submission deadline. Which of the following statements about Lab Prep Assignments is FALSE? A. You will be responsible for completing your Lab Prep Assignments using LabClicker. B. Lab Prep Assignments include videos or demonstrations that will help you prepare for lab. C. Students should wait to submit their answers until right before the submission deadline. D. Lab Prep Assignments are not "timed". You can spend as much time on them as you wish until the due date. E. Lab Prep Assignments must be completed PRIOR to the start of each lab according to the deadline posted in LabClicker

C

Where can I find ALL of my official assignment scores that will determine my overall BIO 206L course grade? A. email from laboratory instructor (TA) B. Classroom Information Pages (CLIPS) C. CANVAS D. Blackboard (Bb) E. ALL of these answers

C

Which of the following is FALSE concerning the state of the microscope when one wishes to remove a specimen slide after viewing? A. The objective with the greatest working distance should be in alignment. B. The scanning objective should be in alignment. C. The objective with the highest magnification should be in alignment. D. The mechanical stage should be lowered.

C

Which of the following lenses does not magnify the object of interest? A. ocular lens B. objective lens C. condenser lens D. all of the above

C

Which type of light would be required to excite a fluorochrome that fluoresced blue? A. Depends on the nature of the fluorochrome B. Blue C. UV D. Red E. Green

C

general equation for dilution

C1V1 = C2V2

For each laboratory exercise, you will receive a 'Lab Performance' grade. You can earn a total of 10 performance points during each lab. To earn all 10 performance points you must: Demonstrate good laboratory technique (4 points possible) Perform clean-up duties (2 points possible) Effectively work as a member of your group (4 points possible) During each lab, your Lab Instructor will evaluate your ability to use a piece of equipment or follow a particular procedure. You can earn up to 4 points for excellent technique. At the end of lab, your Lab Instructor will also evaluate how well you performed the required clean-up duties. You can earn up to 2 points for returning equipment and supplies to their correct location, disposing of waste properly and returning your bench to its starting condition. For each lab exercise, YOU will evaluate each group member's ability to work effectively as a member of your group. Each student can earn up to 4 points total for excellent participation and collaboration skills. Which of the following will your Lab Instructor evaluate? A. If you properly clean-up your work area B. If you demonstrate good lab skills C. If you participate and collaborate with your group members during lab D. If you demonstrate good lab skills AND clean-up your work area E. If you properly clean-up, demonstrate good lab skills, and collaborate with your group members

D

For safety reasons, which of the following must be avoided whenever using a fluorescence microscope? A. touching hot surfaces B. having direct physical or eye contact with the UV light source C. adjusting the alignment of the UV bulb D. All of the above

D

In light microscopy an ocular reticle is used to: A. Determine the resolving power of a microscope. B. Stain a specimen to increase contrast. C. Determine the magnification of a microscope. D. Measure the relative size of an object. E. All of these answers

D

Many enzymes lose their catalytic activity when placed in a hostile environment. What has happened to the enzyme? A. It has become polyunsaturated. B. It has become depolymerized. C. It has become saturated. D. It has become denatured. E. It has become renatured.

D

The ability to distinguish two points in the specimen (i.e., see two points, instead of one) relates to a property of light microscopes termed A. Diffraction or Scattering B. Numerical Aperature C. Contrast D. Resolution E. Focus

D

The types of genes that may be found on plasmids are A. genes that confer resistance to an antibiotic. B. genes that confer the ability to metabolize an unusual food source. C. genes that confer the ability to produce a toxin. D. All of the above.

D

Using the formula weight of Tris (FW = 121.1), how much (to the nearest 0.01 g) is needed to prepare 50 mL of a 0.50 M solution? A. 3.03 mg B. 60.55 g C. 30.29 g D. 3.03 g E. None of these answers

D

What is the proper character to indicate the start of a formula in Microsoft Excel? A. # B. + C. ' D. = E. None of these answers

D

What required materials must you purchase and bring to the first lecture? A. A new copy of the BIO 206L lab manual. B. A used copy of the BIO 206L lab manual. C. A standard lab notebook I don't need to bring any materials to the first lab. I'll just wait to buy my lab manual and notebook after class. D. A NEW copy of the BIO 206L lab manual AND a bound, quadrille-ruled lab notebook.

D

When is it acceptable to focus using the course focus knob? A. When any objective is in alignment. B. Only when the 40X objective is in alignment. C. When there is no objective in alignment. D. Only when the 4X objective is in alignment. E. Only when the 4X objective is not aligned.

D

Which of the following types of microscopy will you NOT use to view specimens this week in lab? A. brightfield micrscopy B. phase contract microscopy C. darkfield microscopy D. electron microscopy E. fluorescence microscopy

D

How should the agar plates be stored to allow effective bacterial growth overnight? A. parafilmed B. rubber-banded together C. properly labeled on the bottom periphery D. place inverted in the 37C incubator E. All of these answers

E

Toothpicks used for collection of human cheek cells are considered to be a(n)? And would be most safely discarded? A. sharps... in the Sharps container B. biohazard... in the Solid Chemical Waste C. biohazard... in the Solid Bacterial Waste D. nontoxic... in the regular trash E. biohazard... in the Biohazard Waste beaker

E

We will use LabClicker during Lectures to ask graded questions. Any personal web-enabled device such as a smart phone, tablet, computer laptop, etc. can then be used to access LabClicker. Because the LabClicker system is used to ask questions during lecture, you are required to bring a web-enabled device to every lecture. If you require additional assistance registering for or using the LabClicker system please email [email protected]. What type of device can be used to access LabClicker? A. A pencil and a piece of paper B. An iClicker remote purchased at the Co-Op C. A CPS remote purchased at the Co-Op D. Email can be used to answer LabClicker questions. E. Any web-enabled device registered using your UTEID online at http://labclicker.com/.

E

Which of the following environmental conditions can affect enzymatic activity? A. Absence of cofactors. B. pH. C. Substrate concentration. D. Temperature. E. All of these choices affect enzymatic activity.

E

Which of the following protocols will you complete during Exercise 5? A. Digest a plasmid with restriction enzymes B. Transform bacteria with a plasmid C. Streak bacteria on agar plates D. Swab your cheeks E. Isolate your DNA F. All of the above

F

-achieved by adjusting the height of the condenser -results in an evenly illuminated field and a bright image without glare

Kohler Illumination

Magnification (M) is defined as:

Mlens = length of an image produced by the lens / length of the object which is magnified to produce the image

How can identifying malaria via microscopy be advantageous/disadvantageous?

advantage: simple and can provide quick results disadvantage: malaria isn't common in the US so this test is not performed regularly and malaria may go unidentified

broad range of enterprises, often using genetically engineered organisms, which result in exploitation of living organisms and their products for commercial use

biotechnology

How does the field of view and depth of focus change with magnification?

both decrease with increased magnification

-produce a bright background field of view -achieve contrast when components in object absorb, refract, or reflect some of the light

brightfield microscope

solution of a weak acid and its conjugate base (or vice versa) that resists changes in pH in both directions

buffer system

gathers light and focuses it on the specimen

condenser

moves the condenser up and down to control the lighting focus on the specimen

condenser knob

determines ability to view the object or image

contrast

-condenser is used that has a central dark stop to achieve contrast. -does not allow light through the center of the condenser

darkfield microscopy

-only light that reaches the specimen is an annulus (concentric ring) of light that comes from the edges of this central stop

darkfield microscopy

controls the diameter of the light beam before it enters the condenser aperture

field diaphragm

-employed by fluorescence microscopy as stains -absorb light of some particular wavelength and emit light of slightly longer wavelength

fluorophores

ventilated work area that carries away noxious fumes and fine powders, and for protecting against exposure to dangerous chemical agents

fume hood

emerging field of applied biology, whereby the information content (i.e. the DNA) of a living organism is permanently changed using the techniques of molecular biology, so that it and its progeny may express one or more traits differently than before the change

genetic engineering

What cell structures were identifiable when viewing the paramecium in Lab 1?

large and small nucleus -pellicle (cell well) -food vacuoles

produces an image when light is passed through glass or other optically transparent lenses.

light microscope

this objective has the greatest field of view and depth of focus

low power objective (4X)

captures and focuses light from specimen and creates a magnified image of specimen

objective

magnifies image 1 from objective to produce image 2

ocular

found in the ocular and is an arbitrary ruler that can be used to measure objects

ocular reticle

what is the method that uses transparent oil with refractive index similar to glass when viewing under a microscope?

oil immersion

prepared when the set of solutions is to contain the component of interest over no more than a 100-fold range of concentration -varied in a linear fashion

parallel dilutions

when an object is in focus with one objective lens, it will be approx. in focus with the others also

parfocal

differences in refractive indices among different components of the specimen produce contrast in the image

phase contrast

the closest that 2 objects (or edges) can be together and still distinguished as separate entities

resolution

prepared when the set of dilutions range over at least two orders of magnitude -varied in geometric fashion

serial dilutions

fluorophores absorb light of some particular wavelength and emit light of _____________ wavlenghth

slightly longer, lower energy

dissolved substances within the solution

solutes

liquid which constitutes most of the molecules of the solution

solvent

calibrates ocular reticle for each objective

stage micrometer

most useful dyes for microscopic observations of cells in order to improve contrast

stains

How can microscopy be used to confirm malaria?

using oil immersion at a 100X objective, the parasites that cause malaria in red blood cells can be viewed within the cells

What two factors impact the resolution distance in a light microscope?

wavelength and numerical aperture (NA)

room equipped with lots of running water and drains, high benches, floors that are easily mopped, surfaces that are relatively inert to chemical agents, and cabinets for storing glassware and chemical substances

wet laboratory