Genetics with Drosophila – Check Test

 

1.         Which of the following is NOT a reason for Drosophila flies

            being suitable for genetic experiments?

            A    They breed very quickly.

            B    Large numbers of offspring are produced.

            C    They are fruit flies.

            D    They have many different phenotypes.

 

2.         The list below shows steps involved in carrying out a cross with Drosophila flies.

            1          Cross the F1 generation together.

            2          Cross the P generation male and female.

            3          Examine the F1 offspring.

            4          Examine the F2 offspring.

 

            What is the correct order of steps?

            A    2, 3, 1, 4

            B    3, 2, 1, 4

            C    2, 3, 4, 1

            D    3, 2, 4, 1

 

3.         In a monohybrid cross, what is the advantage of using parents

            which are true breeding?

            A    The offspring will also be true – breeding.

            B    They will only produce the F2 generation.

            C    There will not be hidden recessive alleles.

            D    There will not be hidden dominant alleles.

 

4.         In a cross between contrasting true – breeding parents,

            a dominant allele can be identified by examining the

            phenotype of the

            A    male parent.

            B    F2 generation.

            C    female parent.

            D    F1 generation.

 

            Questions 5, 6, and 7 refer to a simulated monohybrid cross carried out by several groups in a class.

            Two large beakers were used to represent parent Drosophila flies.

            Beads were used to represent alleles for body colour, grey (G) and ebony (g).

 

5.         Which step in the method below simulates the random nature of the cross?

            A    With eyes closed, a bead is taken from each P beaker.

            B    The two beads are placed together in the F1 beaker.

            C    The beads are carefully returned to the P beakers.

            D    The experiment is repeated several times.

 

6.         The table shows the tally of genotypes obtained by one group of students.

           

Which figures should be entered at X and Y?

           

 

X

Y

A

6

4

B

6

14

C

10

4

D

16

4

 

7.         The total phenotype numbers from the results of the whole class are

            shown in the following table.

           

Grey - bodied flies

Ebony – bodied flies

150

50

           

            What is the phenotype ratio in this cross?

            A    5 grey : 1 ebony

            B    1 grey : 3 ebony

            C    5 grey : 3 ebony

            D    3 grey : 1 ebony 

 

8.         Observed ratios in crosses may differ from theoretical ratios because

            A    large numbers of offspring are produced.

            B    fertilisation is a random process.

            C    the experiment is repeated.

            D    many flies are crossed together.