The preoperational stage is one of the many stages of a child's development. Piaget states that the most obvious change during the preoperational stage is the increase in a child's use language as a symbol or tool for communication. Though they can use language as symbols, they are still not able to form logic or transform ideas into understandable information.
Answer:
a. True
Explanation:
Bruce Wallace was a professor emeritus of genetics who performed many population studies. He worked in 1958 at the University of Cornell as a professor of genetics. In 1963, he performed a population study wherein the recessive allele <em>It </em>was at a frequency of 0.5. The population was propagated for 10 generations and the frequency of <em>It</em> for each generation was determined.
The result of this study showed that<em> lt/lt </em>died without reproducing, whereas, individuals with genotype <em>+/+ </em>were normal.
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.
It would be a catalyst. They help increase the rate of chemical reactions.
