Answer: the expression of certain genes is affected by temperature
Explanation:
For organisms to survive changing environmental conditions, a lot of molecular processes occur in the genes.
For the arctic fox, enzymes coded by specific genes are periodically "switched on or off" depending on the temperature.
Thus, the change in colour can be EXPLAINED by the expression of certain genes affected by temperature
Answer;
-The conservation of "junk DNA" sequences in diverse genomes suggests that they have important functions.
Explanation;
-The term junk DNA refers to regions of DNA that are noncoding. DNA contains instructions (coding) that are used to create proteins in the cell. However, the amount of DNA contained inside each cell is vast and not all of the genetic sequences present within a DNA molecule actually code for a protein.
-Some of this noncoding DNA is used to produce non-coding RNA components such as transfer RNA, regulatory RNA and ribosomal RNA. However, other DNA regions are not transcribed into proteins, nor are they used to produce RNA molecules and their function is unknown.
Answer:
The trait must make the individual more fit to survive. True
Explanation:
Darwin proposed that genetic variations are present in natural populations. Some genetic traits become beneficial under the changed environmental conditions. The organisms with these genetic traits are able to survive and reproduce better than the organisms that lack them. This results in an increased proportion of the beneficial genetic traits in the population over generations as the individuals having those traits reproduce more.
The presence of antibiotic resistance is a beneficial genetic trait that allows bacteria to survive in the presence of antibiotics. Natural selection favors the bacterial having antibiotic resistance and increases their proportions in the population over generations.
