C It controls what is allowed to enter or leave the cell.
Endocrine signaling is hormone based signaling that travels through the blood stream. Many of the sensors and integrating sensors of the endocrine system are located in the brain. The brain barrier contributes to endocrine signalling, such that the brain barrier does not factor in with endocrine signalling. The answer is A
The correct statements are:
•An NLS can be a monopartite or bipartite signal which includes a significant number of basic amino acids.
• The recycling of importins back to their original conformation requires GTP hydrolysis in the cytoplasm.
The other answers are incorrect because GTP is not required for an importin to bind to an NLS but for the release of importin and an NES or nuclear export signal is the sequence in a protein for export from the cell nucleus to the cytoplasm, not to the nucleolus.
After collecting specimens from many areas of the world, Darwin noted the similarities in them. He discovered that new kinds of species could gradually grow into new ones over years.
I hope this helps ;)
