B. some substances must be dissolved in water before they can be used
Flu vaccines need to be revised and changed every year because the flu virus constantly mutates. Flu viruses can change in two ways: drift or shift. Antigenic drift occurs when genes of the virus slowly change during replication until the immune system no longer recognizes it. On the other hand, antigenic shift occurs when a major change in the virus happens. This usually leads to a totally different kind of virus. This is what happened during the H1N1 scare in 2009.
DNA viruses like mumps are less prone to mutation due to the presence of DNA polymerase. RNA viruses are more prone to mutation because they undergo reverse transcription to simulate the role of DNA.
Explanation:
Photosynthesis is a process during which energy from light is harvested and used to drive synthesis of organic carbohydrates from carbon dioxide and water, generating oxygen. Photosynthesis is the only way that radiant energy from the sun can be converted into organic molecules for plants and animals to consume.
<span> descended from land animals</span>. Scientists believed that whales have evolved 50 million years ago from land dwelling ancestors who feed on fish from nearby sea. According to unearthed fossils, the early whale's body was more adapted to land but its relatives are more suited to live in water.
Answer:
maybe something like:
1. what caused their extinction primarily
2. why could they not survive through the situation they were in
3. how do we know what specific event occurred using only the resources we have today
Explanation:
I hope this gave you a bit of insight :))!
