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:
The best description of the events occurring during Ana-phase I of meiosis:
c. Homologous chromosomes randomly separate and migrate to opposite poles.
Explanation:
Meiosis:
It is such type of cell division that occur in animals, plants resulting in four daughter cells and each of daughter cell have the half number of chromosomes from the parent cell.
- Anaphase is one of important phases of meiosis. The option a is incorrect as chromosomes go randomly to opposite poles.
- The option b is incorrect as all of chromosomes inherited from mother and father goes randomly to opposite poles.
- The option c is correct as it is the true description of anaphase I of meiosis.
- The option d is incorrect as the sister chromatids don't separate rather they remain joined.
Answer:
<em>This is an example of natural selection (adaptation).</em>
Explanation:
Natural selection tends to favor those organisms which are better adapted to live in an environment.
As tortoises having flat shell and long neck were better adapted to live in barren area, hence through natural selection those organisms were favored in such an ecosystem.
As tortoises that lived on the vegetative lands were more adapted to live in such an ecosystem, hence through natural ecosystem these organisms were favored and increased in numbers.
<span>Villi are hair-like structures covered with epithelial cells measuring 1.5 mm that line the mucous inner membrane of the small intestine. The epithelial cells of the villi contain microvilli and are responsible for the absorption of nutrients. Being so small and numerous, they effectively increase the absorptive surface area of the small intestine. When the surface area increases, this is the time they absorb the nutrients.
As for plants' root hair cells, they receive nutrients through osmosis. Root hair cells are adapted for this by having a large surface area to speed up osmosis. The absorbed water and minerals are transported through the roots to the rest of the plant where it is used for different purposes: It is a reactant used in photosynthesis.
As we can see, both of them utilize increasing their surface area.</span>
B cytoplasm passes light threw the eye
