What is the root of an evolutionary tree?
A. the tips or ends of the branches that represent the groups being studied
B. the node at the base of the tree representing a common ancestor
C. a branch point representing an extinct ancestral species common to the two connected branches
D. another term for a bifurcating tree
E. refers to the length of each branch of the tree
Which of the following isnot an additional role for nucleosides and nucleotides?
A. primary energy currency of the cell (ATP)
B. electron carrier (NAD+)
C. methyl group donor (S-adenosylmethionine)
D. regulatory molecule (cAMP)
E. catalyst for splicing reactions (dUTP)
Which one of the following copolymeric peptides can be generated in vitro with the synthetic RNA polymer consisting of the repeating dinucleotide (AU)n?
A. (Ile-Trp)n
B. (Ile-Tyr)n
C. (Leu-Asn)n
D. (Tyr-Leu)n
Efforts to define the last universal common ancestor (LUCA) currently estimate 80500 genes are shared by all known species. The lower value of 80 was estimated by determining the number of:
A. mRNAs species produced in LUCA.
B. genes coded by LUCA genome.
C. genes in simplest bacterial species.
D. clearly identifiable orthologs in all organisms.
E. genes required for processes that are found in all organisms.
Which of the following is not true of telomerase function?
A. Telomerase carries a 9-base DNA template complementary to 1.5 repeat units of the telomere sequence.
B. One strand of the telomere sequence is elongated 6 bp at a time.
C. The telomerase repeats its reaction many times in one telomere-binding event.
D. The telomeres extended 3' end is made double-stranded by lagging strand synthesis.
E. The RNA template is repositioned after each extension of the 3' end.
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