A. SeqA binds to hemimethylated DNA and is required for delaying rereplication.

B. As the origins are hemimethylated they bind to the cell membrane and may be unavailable to methylases.

C. The dat locus contains DnaA-binding sites that titrate availability of DnaA protein.

D. Hda protein is recruited to the replication origin to convert DnaA-ATP to DnaA-ADP.

Choose true and false

TLS Online TPP Program

#Question id: 12142

#Unit 10. Ecological Principles

Regarding the geographic range of a species, which of the following statements is true? 

TLS Online TPP Program

#Question id: 19121

#Unit 8. Inheritance Biology

Trisomy 18 is one of the most common trisomies observed in human populations. You prepare DNA samples from two unrelated infants, both with trisomy 18, and from their parents. You then type the infants and their parents for four SSRs distributed along chromosome 18:

 

                                              

In which parent did nondisjunction occur in Family 2?

TLS Online TPP Program

#Question id: 2325

#Unit 2. Cellular Organization

Which of the following is found in BOTH prokaryotic and eukaryotic cells?

TLS Online TPP Program

#Question id: 2863

#Unit 2. Cellular Organization

The promoter of the araBAD operon from E. coli is activated in the presence of arabinose and the absence of glucose and directs expression of genes encoding enzymes required for arabinose metabolism. Unlike the cases of lac and gal genes, where a repressor and an activator work together, here two activators work together: AraC and CAP

+ arabinose	AraC binds that sugar and adopts a configuration that allows it to bind DNA as a dimer to the adjacent half-sites, araI1 and araI2
– arabinose	the AraC dimer adopts a different conformation and binds to araO2 and araI1, there is no monomer at site araI2, and so the protein cannot activate the araBAD promoter (araPBAD). This promoter is also controlled by CAP.

TLS Online TPP Program

#Question id: 4306

#Unit 3. Fundamental Processes

Which of the following molecules helps to "turn off" genes in a cell?