Answer:
Critical thinking requires scientists to ask questions about information they come across and assess its validity. This facet of critical thinking helps them avoid bias that originates from personal opinion and helps them distinguish information and fact from common belief.
Aldosterone increases the reabsorption of sodium ions bringing more back into the blood.
<span>This is the main mineralocorticoid hormone of the adrenal gland. The function of the aldosterone is in the homeostatic regulation of blood pressure, plasma sodium (reabsorption) and potassium levels (excretion).</span>
Explanation:
Microspheres were spherical bodies with metabolic abilities that could successfully sustain their existence. However they did not contain any genetic material. Which means that they could not replicate or pass off their parts to their successive generations.
But they had no way to evolve since they could not pass off any genetic material to their offspring's. This is why RNA came into existence. RNA enabled an Organism to store its genetic material into nucleic acids, that could be passed on to generations to come. This is also how they could evolve into more complex organisms.
Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O
2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".