A portion of the amino acid sequence of an enzyme from a worm is shown below.
-Q-Q-Q-N-N-N-C-C
Analyze the same portion of the same enzyme taken from several other organisms. Place them in order from most closely related to the worm most distantly related to the worm.
-Q-R-Q-N-S-S-C-C- organism X
-Q-Q-Q-N-N-S-C-C- organism Y
-Q-Q-R-N-S-N-C-C- organism Z
a. Z,Y,X
b. Y,Z,X
c. X,Z,Y
d. Y,X,Z
B
I agree.
Was it B?
b is correcet!!!!
Yeah b is correct
1.A
2.B
To determine the order of organisms from most closely related to the worm to most distantly related, we need to compare the amino acid sequences of the enzyme portion in each organism.
Let's compare each amino acid in the sequence of the worm enzyme and the corresponding amino acid in each organism.
For organism X:
-Q-Q-Q-N-N-N-C-C- compared to -Q-R-Q-N-S-S-C-C-
The amino acid sequence in organism X differs from the worm sequence at the second position, where a Q is replaced by an R.
For organism Y:
-Q-Q-Q-N-N-N-C-C- compared to -Q-Q-Q-N-N-S-C-C-
The amino acid sequence in organism Y differs from the worm sequence at the sixth position, where an N is replaced by an S.
For organism Z:
-Q-Q-Q-N-N-N-C-C- compared to -Q-Q-R-N-S-N-C-C-
The amino acid sequence in organism Z differs from the worm sequence at the third, fifth, and sixth positions, where Q and N are replaced by R, S, and N, respectively.
Based on these comparisons, we can conclude that organism X is the most closely related to the worm, then organism Y, and finally organism Z is the most distantly related.
Therefore, the correct answer is option c. X, Z, Y.