Biological soil crusts<span> are communities of living organisms on the </span>soil<span> surface in arid and semi-arid ecosystems. They are found throughout the world with varying species composition and cover depending on topography, </span>soil<span> characteristics, climate, plant community, microhabitats, and disturbance regimes.</span>
(Choice A) A community A contains more resources per individual then Community B
What percent of potassium-40 remains undecayed in a rock that is 3.9 billion years old? The 3.9 billion year old rock has undergone three half-lives (3.9 divided by 1.3 = 3). After 3 half-lives, 12.5% of the potassium-40 remains undecayed.
Answer:
He extracted and observed DNA from white blood cells.
Explanation:
Friedrich Miescher, who is a Swedish Botanist, is the scientist who isolated for the first time. In 1869, Miescher isolated a chemical he called NUCLEIN, which is called Nucleic acid now.
He discovered this so called "NUCLEIN" substance from the nuclei of white blood cells. Nucleic acids are the DNA and RNA we know today, hence, Miescher's discovery was significant to the genetic code as he even agitated for the inclusion of his discovery into inheritance.