Multiple ChoiceIn the life cycle of a fern, the multicellular male gametangium (the sex organ that produces sperm cells) is called a(n) __________. 413views
Multiple ChoiceIn the life cycle of ferns, the multicellular female gametangium (the sex organ that contains an egg) is a(n) __________. 390views
Multiple ChoiceThe "dots" on the underside of a fern frond are spore cases; therefore, what is true of the plant to which the frond belongs? 840views
Multiple ChoiceThe first large forests formed in the Carboniferous period. The decrease in CO2 levels by all of these plants caused __________. 466views