Molecular Genetics of Prokaryotes.

1. Which of the following is not part of the lac operon of E. coli? A. genes for inducible enzymes of lactose metabolism B. genes for the repressor, a regulatory protein C. gene for RNA polymerase D. a promoter, the RNA polymerase binding site E. the operator, the repressor binding site 2. (The role of the inducer of the lac operon). The inducer: A. combines with a repressor and prevents it from binding to the promoter B. combines with a repressor and prevents it from binding to the operator C. binds to the promoter and prevents the repressor from binding to the operator D. binds to the operator and prevents the repressor from binding at this site E. binds to the terminatio... click for more

Molecular Biology (Nucleic Acids and the Genetic Material) Multiple Choice

1. Which scientists first gave experimental evidence that DNA is the genetic material? A Avery, MacLeod, and McCarty who repeated the transformation experiments of Griffith, and chemically characterized the transforming principle. B Garrod, who postulated that Alcaptonuria, or black urine disease, was due to a defective enzyme. C Beadle and Tatum, who used a mutational and biochemical analysis of the bread mold Neurospora to establish a direct link between genes and enzymes. D Meselson and Stahl who showed that DNA is replicated semiconservatively E Watson and Crick who gave a model for the structure of DNA 2. In the Meselson-Stahl DNA replication experiment, what percent of ... click for more

Biology Terms and Concepts

What are Endoplasmic Reticulum and what do they do?

The Centrosome and the Centrioles in Plant and Animal Cells

Do the Centrosome and the Centrioles of the cells act the same in both plants and animals? What are the similarities and differences between animal and plant cells?

Which statistical test should I use?

Im working on an experiment for my A level course (UK) that will determine the effects of different respiratory substrates on yeast population growth. Im using 4 sugars; fructose, glucose, sucrose and lactose. Using a haemocytometer I'll find the size of the yeast population before the sugar is added and the growth 1 week after. I have a choice of 3 statistical tests to choose from: the standard error test; the chi-squared test; and the Mann-Whitney U test. The standard error seems to be the best one to me, but i thought it could only be used for large samples ( at least above 10)?