Biology Lab Review

You are a researchers studying the effects of adhesin, a protein located in the outer membrane of bacterial cells. Which model organism would you choose for your study?

• Mus musculus

• Escherichia coli

• Arabidopsis thaliana

• Drosophilia melanogaster

• Caenorhabditis elegans

Solution A has a concentration of 2.1 mg/ml, while solution B has a concentration of 4.2 mg/ml. In your spectrometer reading, A has a:

• Higher absorbance than B

• Lower absorbance than B

• No difference

• Cannot determine

Solution A has a concentration of 4.2 mg/ml, while solution B has a concentration of 3.0 mg/ml. In your spectrometer reading, A has a:

• Cannot determine

• Lower Absorbance than B

• Higher Absorbance than B

• No difference

The Coomaise dye we added when performing the Bradford assay stains proteins. How does it color change when increasing concentration?

• Blue color intensifies

• Blue color stays the same

• Brown color dimishes

• Blue diminishes

• Brown intensifies

You have a stock solution of protein that you would like to dilute. How much stock protein do you need to add to 800 μL of buffer  to make a 1:5 dilution?

• 200 ul

• 500 ul

• 100 ml

• 100 ul

In an experiment to test the hypothesis "temperature controls sex determination in crocodile embryos" a researchers incubates crocodile eggs in incubators set at different temperatures. Which of the following correctly identifies the dependent and independent variables in the experiment?

• temperature is dependent; sex is independent

• type of incubator is dependent, temperature is independent

• sex is dependent, temperature is independent

• temp is dependent, type of incubator is independent

What dye is used to measure the concentration of proteins in the Bradford Assay we will perform?

• BSA (Bovine Serum Albumin)

• Methylene Blue

• BPB (Bromophenol blue)

• Coomassie blue

Which of the following is NOT a controlled variable in an experiment where a plant is watered with diff liquids and the liquids impact the plant's height and is measured?

• Pot size

• Size of the plant root

• Soil Type

• Plant used

In a Bradford Assay, when absorbance increases, the protein concentration decreases

• True

• False

In a Bradford experiment, you make four dilutions (1:5, 1:10; 1:100 and 1:1000) of an unknown stock protein. Using a BSA control, you produce the standard curve below. The absorbance at 595nm of the 1:10 dilution is 0.7. What is the concentration of the stock solution?

(BSA conc = 1500 ug/ml)

• 1500 ug/ml

• 2000 ug/m

• 15 mg/ul

• 7 mg/ml