Answer:
Explanation:
Meiosis is a form of cell division that occurs in the sex cells of organisms. It ensures the reduction of a diploid cell to an haploid cell to allow for the formation of a diploid zygote after fertilization (contribution of both parents haploid sex cells to give a diploid zygote). Thus, this process is very essential and important.
The reduction is accomplished by 2 divisions after the duplication of chromosomes
- first division: separation of homologous pairs of chromosomes (this reduces the total in half)
- second division: separation of sister chromatids of a chromosome.
The rearrangement in meiosis occurs by crossing over/genetic recombination.
This is the exchange of genetic material between homologous pairs of chromosome bringing about a rearrangement and genetic variation
An example of a chromosomal abnormality that arises as a result of defects in this process is the Down Syndrome which is caused by a nondisjunction of the chromosomes 21 pair in a sex cell.
This condition produces offsprings that have some characteristic facial features, short stature etc
Answer:
Due to the presence of limited number of species.
Explanation:
Bear island provide a great opportunity to decipher entire food chains because this island has many animals species which interact with each other or depend on one another due to the presence of less animals for feeding purpose. This island is isolated from the rest of the world so it provide a great opportunity to study the entire food chains that are present at that island. There is less number of species so knowing about their feeding choices is easier for the ecologists.
Answer:
yaaa you knew that air is everywhere it moves