In the mating Hfr Strs met+ his+ leu+ trp+ Ala+   X F- Strres met- his- leu- trp- Ala-. At regular interval time, the mating cells are interrupted and the cell suspensions plated on four different growth media with streptomycin. The amino acids in the growth media and the number of colonies observed on each are as follows:

Interrupted time	Composition of media					Growth
	His	Leu	Ala	Trp	Met
2   min	+	-	+	+	+	Yes
10 min	+	-	-	+	+	Yes
12 min	+	-	-	+	-	No
15 min	+	-	-	-	+	Yes
20 min	-	-	-	-	+	Yes

What is the order of transfer of the genes?

#Question id: 2771

#Unit 2. Cellular Organization

For SINES (short interspersed elements), which of the following is correct

a. are approximately 300 base pairs long

b.  are LTRs containing retrotransposons.

c. are present in over 1 million copies in the human genome.

#Question id: 2772

#Unit 2. Cellular Organization

Mobile DNA elements likely contributed to the evolution of higher organisms by the

#Question id: 2773

#Unit 2. Cellular Organization

Which of the following is an algorithm designed to compare the sequence of a newly identified protein with sequences already stored in the GenBank database?

#Question id: 2774

#Unit 2. Cellular Organization

The DNA and protein sequences of the -tubulin genes in humans and in fish are similar, and because each arose due to speciation, these genes would be considered:

#Question id: 2775

#Unit 2. Cellular Organization

To examine the folding and compaction of chromatin during mitosis, you will need to isolate and stain chromosomes at a particular stage using a special spreading preparation technique. For the best analysis, the chromosomes must be at which one of the following stages?

#Question id: 2776

#Unit 2. Cellular Organization

There are five major types of histone proteins, but only four of them are considered as core histones. Which one of the following is NOT considered a core histone protein?