Monocotyledons and dicotyledons are the two main types of flowering plants classified according to morphological differences. There are approximately 50,000-60,000 monocotyledon species including lilies, grains, and palms, whereas dicotyledons have 250,000-400,000 species such as daisies and mints. The main difference is the number of cotyledons or seed leaves, but there are also structural variations in their vascular systems, leaf veins, floral parts, pollen, and root development.
Growth Differences Between Monocotyledons and Dicotyledons
1. Compare the Growth of Monocotyledons and Dicotyledons (6 marks)
Monocotyledons and Dicotyledons are the two main types of the angiospermaphyta. They are classified according
to the different morphological characteristics of leaves, flowers and fruit of flowering plants.
There are about 50,000 to 60,000 species belonging to monocotyledons including; lilies, daffodils, grains, sugarcane,
banana, palm, ginger, onions, and others. Whereas there are 250,000 to 400,000 species of dicotyledons like
daisies, mint, pea and grasses.
The main classification difference between monocotyledons and dicotyledons is the number of cotyledons.
Cotyledons are the seed leaves of the embryo and contain nutrition for the embryo till it is able to grow leaves and
produce food by photosynthesis. However there are also other differences in the plant structure of monocotyledons
and dicotyledons such as the arrangement of the vascular system, leaf veins, number of flowering parts, pollen
structure and root development.
The vascular system in dicotyledons is divided into a cortex and stele, whereas in monocots these distinct regions
are absent. Furthermore, the vascular system is scattered in monocots with no particular arrangement whereas in
dicots the vascular bundles consists of primary bundles forming a cylinder in the centre.
Leaf veins are arranged either in parallels through the length of the leaf or in a reticulate arrangement throughout
the leaf. In most species monocots leaves have parallel arrangement whereas dicots have reticulate arrangement.
The number of flower parts is occur in multiples of three in monocotyledons and in multiples of four or five in
dicotyledons .
There is also a different type of pollen structure present in the two classes, monocots developed from plants with a
single pore or furrow in the pollen, whereas dicots developed from plants with a three furrows in their pollens.
Roots can develop either from a main radicle or arise in clusters from the nodes in the stem, called adventitious
roots. Monocots are known to have adventitious roots whereas dicots have a radicle from which a root develops.