State that in a reflex arc the synapse ensure that impulse travel in one direction only

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?

If the rna molecule in a human has the nucleotide sequence of guu, this would the amino acid valine would be needed to make the protein. how would this cha process was occurring in a mushroom?

What's wrong with this ecological pyramid? (multiple choice)1. secondary consumers should be at the bottom of the pyramid2. the sun has an arrow leading to decomposers 3. primary consumers should come after the sun4. energy retained should increase from the bottom to the top5. the sun should be at the bottom of the pyramid