Answer:
the third option, commensalism
Explanation:
Chromosomes exchange genetic material in step 3.
<h3><u>Explanation</u>:</h3>
The meiosis is the type of cell division that takes place for gametogenesis. The meiosis has two phases - meiosis I and meiosis II.
The meiosis I has the events like crossing over and independent assortment which leads to the mixing of genes between homologous chromosome pairs and separation of homologous chromosome pairs. So the two cells that are produced from the meiosis I are genetically different. The step 3 shows the crossing over of prophase 1 of meiosis I. So, it shows the genetic difference between the offsprings and leads to genetic variation.
Answer:
B
Explanation:
This involves selectively breeding two or more populations of a species or subspecies with desirable traits that are wanted by the humans. The offspring of the populations will bear the desired traits from the population. Breeding can be done over generations. An example is the breeding a cattle population that is resistant to drought and another that produces more milk. The filial generations will bear both traits.
B. Upwelling brings cold nutrient rich water to the surface and boosts aquatic life