Answer:
The correct answer is - option e.)
Explanation:
The experiment that was performed by Meselson and Stahl was created to prove that DNA replication is a semiconservative process.
When Bacteria grow on 15N media they incorporate the isotype of nitrogen and after few generations, the culture moved to 14N media where it incorporates as they replicate in semi-conservative mode and one DNA strand comes from the Parent DNA.
The right option for question one is Option (e) Run as one band, at a position expected for DNA containing a 14N:15N ratio equal to 1.
B: during the early stages of meiosis, chromosomes in a homologous pair exchange segments, the process is called Crossing over.
Answer:
The Miller-Urey experiment was conducted to simulate the conditions on Earth when life arose, and see if a chemical evolution could occur. This experiment was performed without oxygen, because they knew that if oxygen was added, the amino acids would oxidize. In particular, the experiment intended to simulate a volcanic eruption was analyzed.
Thus, particles of water, methane, ammonia and hydrogen were exposed to high temperatures and electric discharges that simulated these eruptions, during a determined period. Later, it was observed that organic compounds had emerged from this exposure, which allowed us to infer one of the hypotheses regarding the origin of life on Earth.
Answer:
Convection process
Explanation:
The process of convection is commonly takes place in the mantle portion of the earth and also at the atmosphere.
This process is usually defined as the process where the materials are heated at a high temperature, thereby making them less denser, and due to their low density they are gradually pushed upward into the upper zones. As the materials rises up, the density gradually increases due to the lowering of the temperature, and then the materials again sinks. This give rise to the formations of a circulating cell, which are commonly known as the convection cells.
