Most biology textbooks prior to 1990 listed the major function of ribonucleic acid (RNA) as transferring information from DNA to make proteins. In late 1989, Thomas Cech proposed that RNA had a second major function: as a catalyst for chemical reactions that occur inside the cell. His discovery surprised most scientists and caused the rewriting of many chapters in biology textbooks. What aspect of the scientific process does this best illustrate?

Alichen is an organism that structurally appears to be a single organism. but a lichen is actually two different organisms—a fungus and green algae—living together as one organism. the fungal partner derives its nutrition from the photosynthesizing algae. how does a lichen differ in its photosynthetic activity from elysia chlorotica, the sea slug that’s considered to be a photosynthesizing animal? a. in lichens, the fungi photosynthesize on their own, while elysia chlorotica forms a relationship with a photosynthesizing plant. b. in lichens, the relationship with the algae lasts throughout the life cycle, but in elysia chlorotica, the relationship occurs only during the immature juvenile stage of the slug’s life cycle. c. lichens can photosynthesize only because of the living algal partner, while elysia chlorotica incorporates chloroplasts from algae into its cells. d. in lichens, the association between the fungi and algae is permanent, while elysia chlorotica associates with a photosynthesizing organism only when it requires food.

Consider this plant cell which organelle is labeled g

Milk production during breastfeeding is increased by the suckling of a newborn from his mother's nipple. this type of feedback mechanism best describes a positive or negative