Question

Use the biochemical pathway below to answer this question. Strain 1 and Strain 2 cannot grow on minimal media and are defective at the enzymatic steps indicated on the pathway. Fill in the blanks with + if the strain will be able to grow on minimal media and the intermediate specified or - if the strain cannot grow on minimal media with the intermediate provided.

	Strain 1				Strain 2
A	?	B	?	C	?	D	?	E	?	F

Intermediate	Strain 1 Growth	Strain 2 Growth
A	Answer	Answer
B	Answer	Answer
C	Answer	Answer
D	Answer	Answer
E	Answer	Answer
F	Answer	Answer

Question 2

You are given the biochemical pathway below. Seven mutant strains (labeled S1 - S7) are defective in this pathway and cannot produce the end product when provided with minimal media. Each mutant strain is defective in only the one step indicated by the path. Select all metabolites that when added to minimal media (one at a time) will allow the mutant strain S4 to produce the end product in the reaction. If none of these metabolites will rescue the mutant strain, select "None of These".

S1

S2

S3

S4

S5

S6

S7

Precursor

?

M

?

C

?

P

?

E

?

D

?

G

?

End Product

Select one or more:

C

G

None of These

E

D

M