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Plant Kingdom
Introduction
Does a plant have to be green? Do they all
photosynthesize? They are eukaryotic organisms that are not
animals, fungi, or protists. And yes, they have to
photosynthesize.
What Are Plants?
Plants have adapted to a variety of environments, from the
deserts to oceans. In each environment, plants have become
crucial to supporting animal life. Plants are the food that animals
eat. Plants also provide places for animals, such as insects and
birds, to live. From tiny mosses to gorgeous rose bushes to
extremely large redwood trees, the organisms in this kingdom
have five main features.
All plants...
...are multicellular.
Plants are all multicellular, meaning they are composed of more than one cell. There are no single-
celled plants.
...are photosynthetic.
Photosynthesis is the process by which plants capture the energy of sunlight and use carbon dioxide
from the air (or water) to make their own food: glucose.
Plants have chloroplasts, the organelle of photosynthesis, and are known as producers, or
autotrophs. Most plants have a green color because of the chloroplasts.
...have cell walls.
A cell wall is a rigid, protective layer surrounding cells.
...reproduce using spores or sex cells.
Plants can reproduce asexually or sexually.
For plants, asexual reproduction happens through fragmentation (spores can be blown to different
environments where the offspring then grow to maturity).
Sexual reproduction happens through sex cells (pollen and eggs). Weather or other organisms help
spread pollen from flower to flower.
...have a cuticle.
A cuticle is a waxy layer that covers plants to help keep water in.
Why Are Plants Important?
Plants, and other photosynthetic organisms, are the base for all food chains. Without them, the
herbivores that eat them will slowly die out. After that, the carnivores that eat herbivores will slowly die out
because of the limited food supply. This chain reaction will, over time, kill all life on Earth.
