BIO 141 Exam 3

Put following events of elongation in prokaryotic translation in chronological order

1. Binding of mRNA with small ribosomal subunit 2. Recognition of initiation codon 3. Complementary base pairing between initiator codon and anticodon of initiator tRNA 4. Attachment of the large subunit 5. Base pairing of the mRNA codon following the initiator codon with its complementary tRNA

Hawkweed is a type of sunflower with a diploid number of 8 (2n=8). In the absence of crossing over, how many different combinations of maternal and paternal chromosomes can be packaged in hawkweed gametes?

16

The nucleotide shown above is cordycepin triphosphate. When added to cell extracts, it can be incorporated into a nucleic acid, Based on the chemical structure and your knowledge of cellular processes, where would you expect to find cordycepin incorporated?

3' end of RNA

A diploid cell has 24 chromosomes. How many DNA double helices would be present at the beginning of mitosis?

48

The coding portion of the Grit gene is 1500 nucleotides, including the stop codon. How many amino acids are in the Retriever protein?

499

Which of the following represents a silent mutation?

AGA to CGU. Codons are same

Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the...

Binding of the anticodon to the codon AND attachment of amino acids to tRNAs by aminoacyl tRNA synthetases

In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts?

DNA contains phosphorus, whereas protein does not

Which amino acid would you expect a tRNA with the anticodon 5'-AAG-3' to carry?

Leucine

In the process of transcription

RNA is synthesized

What happens to mRNA after the termination of translation?

The mRNA remains in the cytosol and may be translated again

Which of the following would you expect of a eukaryote lacking telomerase?

a reduction in chromosome length in gametes

The MPF protein complex turns itself off by

activating a process that destroys cyclin components

Homologous chromosomes

carry information for the same traits

The "one-gene, one-enzyme" hypothesis states that

each gene contains the information necessary to make one enzyme

If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in the diploid state?

fertilization

If a base-pair change occurs during DNA replication, this

is a mutation

Sister chromatids separate from each other during

mitosis and meiosis II

Aflatoxin is a compound produced by some types of mold that can cause DNA damage. It chemically modifies DNA, distorting the DNA helix. What cellular mechanism would you expect to be involved in fixing DNA damaged by aflatoxin?

nucleotide excision repair

If a cell has accumulated DNA damage, it is unlikely to

pass the G2 checkpoint

The bacterium Bacillus anthacis, known as anthrax, causes an often fatal disease called anthrax. The antibiotic ciprofloxacin a DNA synthesis inhibitor is used to treat anthrax. For ciprofloxacin to be useful with minimal side effects it must inhibit...

prokaryotic DNA synthesis proteins only

Movement of the chromosomes during anaphase would be most affected by a drug that prevents

shortening of microtubules

Which molecule or reaction supplies the energy for polymerization of nucleotides in the process of transcription?

the phosphate bonds in the nucleoside triphosphates that serve as substrates