In an organism such as a sea urchin, administration of actinomycin D prevents RNA synthesis. However, early development up to gastrula formation can take place in the presence of actinomycin D but gastrulation cannot. This implies that __________
A) development beyond gastrulation requires actD
B) actD is part of the normal environment of a sea urchin and serves as a developmental signal molecule
C) actD receptors begin to form only on cell surfaces of the gastrula
D) maternal effect genes regulate development until gastrulation
E) immature sea urchin embryos produce actD to regulate further development
D
You might also like to view...
The order Lactobacillales within Firmicutes are also called the lactic acid bacteria, because these bacteria
A) can aerobically catabolize lactic acid. B) can ferment lactate. C) produce lactate. D) uniquely require lactic acid as a precursor for cell wall biosynthesis.
A transposon is
A) a DNA segment that can insert itself at one or more sites in a genome. B) a "jumping gene." C) a DNA segment that may cause mutations in genes or chromosomal rearrangements. D) a mobile genetic element that may or may not leave a copy of itself in its original site when it moves to a new site. E) All of these
What are the primary female reproductive organs that are responsible for producing egg cells?
What will be an ideal response?
Match the definition with the term it is describing.
Competent cell A) Taking up plasmid DNA from the environment B) Plasmid containing genes from different organisms C) Cell capable of transformation