In a ____________ study, both the researchers and the participants are unaware of the group assignments.

Between work, school, and taking care of her sick mother, Rosemary has found herself regularly forgetting things for class. Her memory failures may in part be due to the fact that the cortisol released during her stress impairs functioning of the ____ .

When adult amphibian skin harbors populations of the bacterium Janthinobacterium lividum (Jl), chytrid infection seems to be inhibited. Which of the following represents the best experimental design for conclusively determining whether this inhibition is real?

Plant biotechnology is an effective tool for

What typically results from double fertilization in angiosperms?

When diatoms die, their shells fall to the floor of the ocean or lake that they inhabit and form sediments called diatomaceous earth (DE). Diatoms can be identified by their shells. Different species of diatoms prefer different water temperatures. What information can be gained if scientists take samples of long-existing DE and identify the diatom species that created it?

A plant has the following characteristics: a taproot system, several growth rings evident in a cross section of the stem, and a layer of bark around the outside. Which of the following best describes the plant?

Which of the following arise, directly or indirectly, from meristematic activity?

Which of the following pollinating agents is correctly matched with the type of plant it helps pollinate?

Imaging of the thyroid takes place: