Photoexcitation<span> is the photoelectrochemical process of electron excitation by photon absorption, when the energy of the photon is too low to cause photoionization. The absorption of the photon takes place in accordance with Planck's quantum theory.</span>
Robin can have a ddt concentration of 444ppm while the ddt concentration of soil is 10 ppm. This happens due to biological magnification.
<u>Explanation:</u>
In biological magnification the concentration of toxic substances at successive trophic levels keeps increasing. Due to biomagnification, what starts out as a small concentration grows while moving to successive trophic levels. DDT is a pesticide which is used to kill pests that affect crops.
DDT used in farms gets deposited in the soil. From the soil it can reach various trophic levels. At each trophic level its concentration keeps increasing.
Robin is a bird that is a secondary consumer and thus belongs to the higher trophic level. Thus even if the DDT concentration is as low as 10ppm in the soil its concentration will keep increasing and can become a high value like 444ppm.
No change. Change happens only when placed in a culture media.
Hope this helps you
Hair plays an important role in our lives. The hair on our head keeps us warm and acts as a cushion for our skull. Hair appearance can also help form our identity and self-image, which makes hair loss very troubling.
Most hair disorders aren’t serious, but they are often considered major cosmetic issues that require treatment. Androgenetic alopecia is the most common form of hair loss, although there are a number of other hair conditions that can affect the scalp and other parts of the body.
Answer:
The correct answer will be option-E
Explanation:
Hershey and Chase's experiment was performed to test whether DNA serves as the genetic material or protein.
To perform experiment they grew bacteriophage into radiolabeled phosphorus and sulfur compounds. The phosphorus is an integral part of the structure of DNA whereas proteins contain sulfur in their structure.
In the given condition if radiolabeled nitrogen is utilized then the experiment will fail as the structure of proteins also contains an amino group( NH₂) in their structure as well as DNA. The scientist will not be able to identify whether the DNA is the genetic material or protein.
Thus, option-E is the correct answer.