Question

table 8.1
culture 1: f+, leucine+, histidine+
culture 2: f-, leucine-, histidine-

in table 8.1, what will be the result of conjugation between cultures 1 and 2 (reminder: f+ has a different meaning than hfr)?

a 1 will remain the same;
2 will become f+, leu+, his+

b 1 will remain the same;
2 will become f+, leucine-, histidine-

c 1 will become f-, leu+, his+;
2 will become f+, leu-, his-

d 1 will remain the same;
2 will become f+ and recombination may occur

e 1 will become f-, leu-, his-;
2 will remain the same

Explanation:

In bacterial conjugation, F+ cells transfer the F plasmid to F- cells, converting them to F+. Unlike Hfr cells, F+ cells rarely transfer chromosomal genes (like those for leucine/histidine synthesis) efficiently. Thus, Culture 1 (F+, leu+, his+) remains unchanged, and Culture 2 (F-, leu-, his-) becomes F+ but retains its leu- and his- phenotypes unless rare recombination occurs.

Answer:

D. 1 will remain the same; 2 will become F+ and recombination may occur