Exam 14: Translation and Proteins

The primary structure of a protein is composed of the sequence of amino acids in that protein.

Describe the basic structure of normal adult hemoglobin and the abnormality observed in sickle-cell hemoglobin.

The accompanying drawing represents simultaneous transcription and translation in E.coli.The direction of the RNA polymerase is given by the arrow. (a) Is the letter A nearer the 5′ or the 3′ end of the molecule? (b) Is the letter B nearer the 5′ or the 3′' end of the molecule? (c) Is the letter C nearer the 5′ or the 3′' end of the tRNA molecule? (d) What is the "S" value for the large rRNA that is closest to the letter D? (e) Which terminus (N orC)of the growing polypeptide chain is nearer to the letter E?

Considering the types of side chains on amino acids and their relationship to protein structure,where are the amino acids with hydrophobic side chains most likely to be located?

The β chain of adult hemoglobin is composed of 146 amino acids of a known sequence.In comparing the normal β chain with the β chain in sickle cell hemoglobin,what alteration is one likely to find?

Below are several phenomena relating to protein structure.Clearly describe each phenomenon,the conditions under which each occurs,and the probable influence each has on protein structure. (a) hydrophobic interactions (b) hydrogen bonds (c) disulfide bridges

Proteins are composed of strings of nucleotides connected together by 5′-3′ phosphodiester bonds.

Describe the conceptual basis for constructing biochemical pathways using nutrient supplement experiments with Neurospora.

The secondary structure of a protein is dependent on polar interactions among the side chains of the amino acids.

rDNA is the portion of a genome that is involved in the production of ribosomal RNA.

What are polyribosomes?

The primary structure of a protein is determined by ________.

Three major types of RNAs are mRNA,rRNA,and tRNA.For each of the conditions below,predict the consequences in terms of the population of proteins being synthesized in a particular cell.What qualitative and quantitative changes,if any,are expected in the individual protein involved (if one is involved)and in the population of proteins in this cell? (a)An acridine dye-induced mutation (adds or deletes single bases in DNA)leads to an mRNA for one protein-producing gene.The condition is heterozygous in the involved cell. (b)A deletion (homozygous)that removes approximately half of the rRNA genes.

Assume that a base addition occurs early in the coding region of a gene.Is the protein product of this gene expected to have more or fewer altered amino acids compared with the original gene with a base deletion late in the coding region?

A protein is 300 amino acids long.Which of the following could be the number of nucleotides in the section of DNA that codes for this protein? (Remember: DNA is double-stranded.)

Which of the following are among the major components of prokaryotic ribosomes?

Sickle-cell anemia is caused by the absence of the alpha chain of hemoglobin.

Much has been learned about the relationship between genes and gene products through the use of the mold Neurospora.What specific attributes make Neurospora a good organism for such studies?

The secondary structure of a protein includes ________.

The one-gene:one-enzyme hypothesis emerged from work on which two organisms?