A Level Biology Practice Exam

What characterizes dicotyledonous plants (dicots)?

1. Single cotyledon in seeds

2. Presence of thorns and spines

3. Seeds with two cotyledons

4. Non-flowering plants

The correct answer is: Seeds with two cotyledons

The defining characteristic of dicotyledonous plants, commonly referred to as dicots, is indeed the presence of seeds with two cotyledons. Cotyledons are the first leaves that develop from the seed during germination, and having two of them is a key feature that distinguishes dicots from monocotyledonous plants, which have only one cotyledon. This distinction is significant in the classification of flowering plants, as dicots typically exhibit additional traits such as net-veined leaves, flower parts in multiples of four or five, and a vascular system organized in a ring. Understanding these characteristics helps in identifying and categorizing various plant species within the broader context of botany.