Answer:
The correct answer is option a.
Explanation:
Osteoporosis refers to a condition that weakens the bone, and enhances the threat of unanticipated and sudden fractures, also known as porous bones. It leads to an enhanced loss of bone mass and strength. The disease often advances without any kind of pain or signs.
There is a direct association between the reduction of estrogen post menopause and the emergence of osteoporosis. Postmenopause, the breakdown or resorption of bone takes over the formation of novel bone. Estrogen diminishes the function and number of osteoclasts. Thus, the reduction in the levels of estrogen after menopause leads to bone loss.
Answer:
The correct answer is b. must be present in a population before natural selection can act upon the population
Explanation:
Genetic variation can be caused by mutation, recombination between chromosomes during meiosis and by fusion of two genetically different gametes during sexual reproduction.
This genetic variation is necessary for the evolution of any population. Natural selection acts on every individual and it decreases the frequency of those alleles that are not suited for the environment and increase the frequency of those alleles which helps the individual to survive in the changing environment.
Therefore genetic variation must be present in the population before natural selection act on the.
According to the research, this new species most likely belongs to the Protista kingdom since it has a defined nucleus.
<h3>What is the Protista kingdom?</h3>
They are unicellular or multicellular microorganisms that, for the most part, feed autotrophically, and that, on the other hand, cannot be included in the remaining three kingdoms of eukaryotes.
It can be both autotrophic and heterotrophic by photosynthesis, although many of them combine both forms of nutrition and have chloroplasts, mitochondria, a defined nucleus, among other structures.
Therefore, we can conclude that according to the research, this new species most likely belongs to the Protista kingdom since it has a defined nucleus.
Learn more about Protista kingdom here: brainly.com/question/925018
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