28. Plants

Besides the plant tissue that humans ingest, which angiosperm tissue is most directly important for human survival?

Like gymnosperms, many grasses and angiosperm trees are wind-pollinated. To conserve energy, these angiosperms do not produce complete flowers (complete flowers have all four of the basic parts). Which part would be unnecessary for wind-pollinated angiosperms?

What is located in the scalelike structures packed densely in pollen cones?

The cells within pollen grains are __________ and together comprise the __________.

Dietary supplements and decongestants containing ephedrine have recently become more strongly regulated in the United States. Which phylum contains the plant from which ephedrine is extracted?

The closest seedless relatives of seed plants produce one kind of spore that gives rise to a bisexual gametophyte. What does this suggest about the ancestors of seed plants?

Which types of angiosperms would most likely be wind-pollinated rather than animal-pollinated?