Deck 2: Drosophila Life Cycle and Development of the Body Plan

Question 1

What is the result of the first 12 nuclear divisions of a Drosophila embryo where roughly 6,000 nuclei share a single cytoplasm?

A) Micropyle
B) Cellular blastoderm
C) Syncytium
D) Pole cell

Answer 1

C

Question 2

Which of the options given is not true of the Drosophila mesoderm?

A) It gives rise to muscle and connective tissue.
B) Gastrulation internalizes the mesoderm.
C) The mesoderm is a primary germ layer.
D) The dorsal surface of the blastoderm gives rise to mesoderm.

Answer 2

D

Question 3

Which term is not associated with a Drosophila larva?

A) Instar
B) Metamorphosis
C) Denticles
D) Imaginal discs

Answer 3

B

Question 4

What is the maternal anterior morphogen that controls head and thorax development?

A) Bicoid
B) Nanos
C) Caudal
D) Torso

Question 5

Which of the options given is not true of the Drosophila Dorsal protein?

A) Control regions of target genes differ in their affinity for the Dorsal protein.
B) The dorsal region of the Drosophila embryo expresses genes that are repressed by the Dorsal protein.
C) The gradient of Dorsal protein divides the Drosophila embryo up into at least four well-defined domains.
D) Dorsal protein levels are higher within the dorsal region of the Drosophila embryo.

Question 6

What class of patterning genes are expressed within seven transverse stripes in the Drosophila embryo?

A) Pair-rule genes
B) Segmentation genes
C) Gap genes
D) Hox genes

Question 7

What class of patterning genes encodes members of intercellular signaling pathways?

A) Pair-rule genes
B) Segmentation genes
C) Gap genes
D) Hox genes

Question 8

Which of these segmentation genes is a transcription factor that defines parasegment boundaries?

A) Frizzled
B) Hedgehog
C) Patched
D) Engrailed

Question 9

What is the term that describes the relation between the order of the Hox genes along the chromosome and the order of their expression along the antero-posterior axis?

A) Homeosis
B) Posterior dominance
C) Gene cluster
D) Co-linearity

Question 10

What type of gene, such as a Hox gene, is sufficient to cause cells to adopt a particular fate?

A) Selector
B) Repressor
C) Activator
D) Recessive