Question

1. how can you tell the difference between alternate and opposite leaf arrangements?

they are based on based whether the leaf pinnate or palmate venation.
they are based on whether the leaf has one or two leaves at the node.
they are based on whether the leaf is simple or compound.
they are based on based whether the leaf has a smooth or toothed margin.

Explanation:

Leaf arrangement refers to the pattern of leaf attachment to the stem. In alternate leaf arrangement, there is one leaf at each node on the stem. In opposite leaf arrangement, there are two leaves at each node, directly opposite each other. Venation (pinnate or palmate) refers to the pattern of veins in a leaf, not leaf arrangement. Whether a leaf is simple or compound refers to the leaf structure (a single blade vs multiple leaflets). Leaf margin (smooth or toothed) refers to the edge of the leaf.

Answer:

They are based on whether the leaf has one or two leaves at the node.