Select all of the following that describe RNA. Check all that apply.
nucleotides contain the sugar deoxyribose
always occurs as a double-stranded helix
can be single-stranded
can catalyze chemical reactions
the nitrogenous base thymine is used instead of guanine
the nitrogenous base uracil is used instead of thymine
nucleotides contain the sugar ribose

The asian shore crab (hemigrapsus sanguineus) is an invasive species that has impacted the atlantic coast. predict what characteristic of this invader would most likely disrupt the biodiversity of this area.

Recently, crops of vegetables such as lettuce and green onions have been contaminated, while they are still on the farm, with bacteria that cause food poisoning. how will science influence the way the government responds to prevent an increase in food-borne diseases? because science has shown that lettuce and green onions are not nutritionally valuable, the government may pass laws that ban the sale of lettuce and green onions. because science has shown that there is no way to prevent bacterial contamination, the government may pass laws that punish businesses that buy lettuce and green onions. because science has shown that the washing of hands prevent the spread of infectious diseases among people, the government may pass laws that require hand washing by everyone who handles food. because science has shown there are ways to find the source of the contamination, the government may pass laws that require farm practices that reduce the contamination of lettuce and green onions.

Tom wants to conduct a scientific study but he needs to finish by the end of the school year. what practical way could tom work around this limitation and be successful in his study?