Answer:
In humans, genetic variations are caused because humans reproduce by a sexual life cycle which is termed as meiosis. In such a life cycle, the offspring receives half the chromosomes from the mother and half from the father. Crossing over and random assortment of chromosomes are two phenomenons which occur during meiosis. Due to these two phenomenons, genetic variations are caused.
During crossing over, the exchange of DNA segments between the homologous chromosomes takes place which brings about the genetic variations.
Biodiversity is essential to an ecosystem's resistance against viruses and famine. In history, there has been many cases in which a lack of biodiversity has allowed a virus or disease to endemically wipe out an entire species of plant. This will subsequently affect all consumers of each trophic level. Ex: A disease that attacks the DNA of only one certain species of plant would cause decreases in the population of the organisms that rely on eating that plant, the organisms that rely on eating those organisms, and so on. This is caused by a decrease in food source, thus not being able to sustain the ecosystem's demand, thus naturally killing off any organisms that would not be able to find a sufficient food source.
Hello love! The answer for your question is D: grass - producer because all energy starts from the producers so the consumers can get energy. Producers are the creators of energy
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Answer:
The word acidification can be misleading because a pH of 7.9 is still considered slightly alkaline. However, as the graphs in these three locations show, as CO2 rises, the pH drops, moving in the direction of the acidic end of the pH scale.
Explanation:
Answer:
D) largest mass extinction event in Earth's history
Explanation:
The cambrian era started following the pre-cambrian extinction
