It is difficult to observe individual chromosomes with a light microscope during prophase
because
A. The DNA has not been replicated yet
B. They are uncoiled, in long, thin strands
c. They leave the nucleus and are dispersed to
other parts of the cell
D. The spindle must move them to the metaphase
plate before they become visible​

it has one origin of replication, but it proceeds in two directions - d)

the electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, x-rays, and gamma-rays.

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.  

the answer is d p: cell, q: organ, r: organ system, s: tissue