The cilia lining the upper respiratory passages (superior to the larynx) beat inferiorly, whereas as the cilia lining the lower respiratory passages (larynx and inferior) beat superiorly. what is the functional reason for this difference?

The cilia in the upper respiratory tract move mucus  down toward the pharynx whereas the cilia in the  lower respiratory tract move them up toward the pharynx.

Explanation:

Through the internal nares, the air enters nasopharynx from the nasal cavity. This air has dust-laden mucus. The nasopharynx is lined with ciliated pseudostratified columnar epithelium. These cilia move the mucus down toward the most inferior part of the pharynx. The lining of the larynx inferior to the vocal folds is made up of ciliated pseudostratified columnar epithelium and have ciliated columnar cells, goblet cells, and basal cells.

The goblet cells serve to produce and secrete mucus. The mucus from goblet cells helps trap dust that was not removed in the upper passages. Therefore, the cilia in the upper respiratory tract move mucus and trapped particles down toward the pharynx whereas the cilia in the lower respiratory tract move them up toward the pharynx.

coconut why: has water in it : )

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.