1. The lining up of chromosomes by the spindle fibers takes place at metaphase II phase. It is the second stage of meiosis II, the spindle draws the chromosomes towards the metaphase plate.
2. The formation of the nuclear envelope around each set of DNA takes place in telophase II. Along with the formation of the nuclear envelope, the process of cytokinesis also takes place in telophase II, producing four daughter cells, each comprising a haploid set of chromosomes.
3. The sister chromatids are pulled apart in anaphase II stage. In this phase, the sister chromatids are migrated towards the opposite poles of the cell with the help of protein fibers.
4. The centromeres are moved towards the poles of the cell at prophase II stage.
The correct answer to fill in the blank would be C) Semicircular canals.
The answer to this question is c
Lakes that have been acidified cannot support the same variety of life as healthy lakes. As a lake becomes more acidic, crayfish and clam populations are the first to disappear, then various types of fish. Many types of plankton-minute organisms that form the basis of the lake's food chain-are also affected. As fish stocks dwindle, so do populations of loons and other water birds that feed on them. The lakes, however, do not become totally dead. Some life forms actually benefit from the increased acidity. Lake-bottom plants and mosses, for instance, thrive in acid lakes. So do blackfly larvae.