Answer:
B. Nucleic acids absorb UV light maximally at wavelengths of 254 to 260. Proteins absorb UV maximally at 200 nm. Using this phenomenon, one can to determine the presence and concentration of nucleic acids in a mixture.
Explanation:
The concentration of a solution of nucleic acid can be determined by measuring the absorbance at 260 nm, using a spectrophotometer. An A260 of 1.0 is equivalent to a concentration of 50 μg/mL for double-stranded DNA, or 40 μg/mL for single-stranded DNA or RNA. If the A280 is also determined, the A260/A280 ratio indicates if there are contaminants present, such as residual phenol or protein. <u>The A260/A280 ratio should be around 1.8 for pure DNA and 2.0 for pure RNA preparations.</u>
Answer:
the 3rd choice and ignore this stuff because brainly makes me write an answer with 20 letters for some reason
Answer:
How do you want me to answer this
Explanation:
The correct answer is - 1) inverted pyramid, with a narrow base representing a small number of young individuals.
The populations that are decreasing are usually population in countries that are highly developed. The conditions for living are excellent, the medical care on high level, life expectancy very high, but the birth rates very low.
In this type of conditions, there's smaller and smaller number of young individuals, with the middle aged population being much bigger, and the older population being constantly on the rise. This will give the age-structure histogram a reverse shape than what it is supposed to have, it will be similar in appearance like a inverted pyramid, meaning that the population is aging and that it will be constantly on a decline in the future.
