#Question id: 5660
#Unit 5. Developmental Biology
Following statement regarding to acrosome reaction in sea urchin.
A. Activation of the acrosome reaction serves as a barrier to intraspecies fertilizations.
B. The acrosome reaction is initiated by sulfate-containing polysaccharides in the egg jelly that bind to specific receptors located directly above the acrosomal vesicle on the sperm cell membrane.
C. These polysaccharides are often highly species specific, but egg jelly factors from one species of sea urchin generally activate the acrosome reaction in closely related species.
D. The elevated Ca2+ level in a relatively basic cytoplasm triggers the fusion of the acrosomal membrane with the adjacent sperm cell membrane, releasing enzymes that can lyse a path through the egg jelly to the vitelline envelope.
Which of the following statements are correct?
#Question id: 3897
#Unit 3. Fundamental Processes
Gene silencing by RNA interference acts by of the target gene.
#Question id: 18675
#Unit 13. Methods in Biology
#Question id: 10494
#Unit 6. System Physiology – Plant
Sucrose is an osmotically active solute in guard cells, One implication of these osmoregulatory features is that stomatal opening & closing is associated with which of the following given statements?
#Question id: 794
#Unit 1. Molecules and their Interaction Relevant to Biology
A single-stranded DNA molecule contains 40 nucleotides with equal amounts of A, C, G, and T. This DNA strand can combine with a complementary DNA strand to form a double-stranded DNA molecule. Which structural feature is found in the single-stranded DNA molecule?