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:
b
Explanation:
The purpose of the strand B be would be <u>to carry the code from the DNA molecule in the nucleus to the ribosome.</u>
<em>Looking closely at the diagram, strand B is the strand of RNA that is still in the process of being synthesized while strand A is acting as the template. The function of the RNA strand is primarily to carry an encoded message in the DNA molecule from the nucleus to the ribosome in the cytoplasm where the genetic codes would be translated during the process of protein synthesis.</em>
The correct option is, therefore, b.
<span>Stratum Basale, being the deepest stratum of skin, will be supplied with the highest levels of oxygen from the blood. The Stratum Basale is constantly renewing and must be supplied with oxygen in order to keep renewing. The other stratus are more superficial and further from the blood source and also do not require quite as much oxygen.</span>
Answer:
Phagocytosis refers to the engulfing of larger, solid particles. Often, the engulfed particle is another cell, like when a white blood cell, which is a part of the immune system, engulfs a bacterium to destroy it.