It is know as smoke because if you cook food smoke will go up in the air and that makes vapor and also water from the ground it suck up
Not entirely sure if you're saying Homologous , but assuming you do , the homologous chromosomes seperate in the anaphase stage of Mitsosis of the Cell cycle
Answer;
A plain
Explanation;
A contour line connects points of the same elevation. Contour lines are usually curves. Closed contours represent hills.
Contour lines can not cross since they represent different elevations. A contour interval is the difference in elevation between one contour and an adjacent contour.