You have collected 6 strains of D.melanogaster. Each strain is homozygous for a

Question

You have collected 6 strains of D.melanogaster. Each strain is homozygous for a body color mutationwhich is recessive to the wild type body color. You perform thefollowing set of complementation crosses and observe the followingresults:


1
2
3
4
5
6
1
X
-
+
+
+
+
2
-
X
+
+
+
+
3
+
+
X
+
-
+
4
+
+
+
X
+
-
5
+
+
-
+
X
+
6
+
+
+
-
+
X



(Hint: The table shows the results of many different crosses. The square marked by 1 and 1 (top most left square) has an X in itbecause we already know that members of stock one have the samemutant allele at the same gene so we don't test it. The nextsquare going across the top line has a minus in the square. That means that in a cross of stocks 1 and 2 the progeny had amutant phenotype. The third square in the top row represent across of Stocks 1 and 3. There is a plus in the square toshow that the progeny from this cross had a normalphenotype.

Group the strains by which strains share mutant alleles of the samegene. See how many different groups you have. Each group willrepresent a different gene.)

How many different genes are there in these groups? a. 4 b. 6 c. 3 d. 2 e. None of theabove.

Explanation / Answer

b. 6 1 2 3 4 5 6 1 X ------ + + + + 2 -------- X + + + + 3 + + X + ----- + 4 + + + X + -------- 5 + + ------ + X + 6 + + + ------ + X

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.