Questions | 5 |
Topics | Cell Division, Cold Front, Comets, Groups, Velocity |
Cell division is the process by which cells replicate genetic material in the nucleus. Cell division consists of several phases:
Phase | Major Process |
---|---|
interphase | chromosomes replicate into chromatids and the cell grows |
prophase | chromatids pair up |
metaphase | paired chromatids move to opposite sides of the cell |
anaphase | cell elongates and nucleus begins to separate |
telophase | separation of nucleus is complete resulting in two new nuclei |
cytokinesis | cytoplasm and cell membranes complete their separation resulting in two separate cells |
A cold front is a warm-cold air boundary with the colder air replacing the warmer. As a cold front moves into an area, the heavier cool air pushes under the lighter warm air that it is replacing. The warm air becomes cooler as it rises and, if the rising air is humid enough, the water vapor it contains will condense into clouds and precipitation may fall.
A comet is a loose collection of ice, dust, and small rocky particles that, in contrast to an asteroid, has an extended atmosphere surrounding the center. When passing close to the Sun, this atmosphere warms and begins to release gases forming a visible coma or tail.
The columns of the Periodic Table are called groups and all elements in a group have the same number of electrons in their outer electron shell. The group that an element occupies generally determines its chemical properties as the number of outer shell electrons establishes the way it reacts with other elements to form molecules. So, because each element has the same number of electrons in its outer shell, each has similar reactivity.
Velocity is the rate at which an object changes position. Rate is measured in time and position is measured in displacement so the formula for velocity becomes \(\vec{v} = { \vec{d} \over t } \)