Question

A dichotomous key is used to identify a plant below.

1a. Leaves are spiny.................................Pinus taeda

1b. Leaves are broad...............................Go to 2

2a. Single leaf..........................................Go to 3

2b. Many leaves.......................................Go to 4

3a. Leaf edge is smooth...........................Cornus florida

3b. Leaf edge is rough.............................Ulmus americana

4a. Leaflet edges are smooth..................Albizia julibrissin

4b. Leaflet edges are rough....................Juglans nigra



A plant has a broad single leaf with smooth edges. What type of plant is this?

(1 point)
Responses

Pinus taeda
Pinus taeda

Cornus florida
Cornus florida

Juglans nigra
Juglans nigra

Ulmus americana

Answer 1

The plant described as having a broad single leaf with smooth edges corresponds to the following steps in the dichotomous key:

1b indicates it has broad leaves, so we go to step 2.
2a indicates it has a single leaf, so we go to step 3.
3a indicates the leaf edge is smooth.

According to the key, a broad single leaf with smooth edges identifies the plant as **Cornus florida**.