Erwin and Scott used an insecticidal fog to knock down insects from the top section of a L. seemannii tree. The researchers identified over 900 species of beetles among the individuals that fell. Erwin also projected that this entire tree from top to bottom is host to about 600 arthropod species that are unique to this tree species and not found on any other tree species. There are approximately 50,000 species of tropical trees. Although it could not be entirely accurate, what would be the best way to estimate the total number of arthropod species?

#Question id: 4272

#Unit 3. Fundamental Processes

There are two classes of release factors for translation termination. Choose correct statements

A. Class I release factors recognize the stop codons and trigger hydrolysis of the peptide chain from the tRNA in the P-site.

B. Prokaryotes have two class I release factors called RF1 and RF2. RF1 recognizes the stop codon UGA, UAA and RF2 recognizes the stop codon UAG and UAA.

C. In eukaryotic cells, there is a single class I release factor called eRF1 that recognizes all three stop codons.

D. Class II release factors stimulate the dissociation of the ribosome after release of the polypeptide chain.

#Question id: 4273

#Unit 3. Fundamental Processes

80S initiation complex includes

#Question id: 4274

#Unit 3. Fundamental Processes

One mechanism that contributes to the fidelity of codon recognition involves the 16S rRNA other than initiation. Which of the following statements are correct in this phenomenon?

A. Codon recognition involves two adjacent uracil residues in the 16S rRNA component

B. The adjacent residues in the 16S rRNA do not discriminate between G:C or A:U base pairs and recognize either as correct

C. Even a single mismatch in the codon–anticodon base pairing alters the position of EF-Tu, reducing its ability to interact with the factor-binding center 16s rRNA, leads to a dramatic reduction in EF-Tu GTPase activity

D. Pyrophasphatic editing is key mechanism to ensure fidelity

#Question id: 4275

#Unit 3. Fundamental Processes

CCA-adding enzymes add a specific sequence without a template because

#Question id: 4276

#Unit 3. Fundamental Processes

Which of the following post-translational modifications of proteins occur(s) in the lumen of the endoplasmic reticulum?

a. glycosylation                       b. formation of disulfide bonds

c. conformational folding and formation of quaternary structure

d. proteolytic cleavage                        e. aldol condensation of sugars

#Question id: 4277

#Unit 3. Fundamental Processes

N-linked oligosaccharides in glycoproteins